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patrickcollison.com

315 pointskmax12239 comments

> At peak, renewables provide up to ~90% of California's electricity

In fact, renewable generation regularly hit more than 100% of load in California during April and June of this year. The peak was 132% of load [0]!

How can generation be more than 100% of load? California was exporting power to other regions.

We track all this data and more across the United States at Grid Status: https://www.gridstatus.io/home

[0] https://www.gridstatus.io/records/caiso?record=Maximum%20Ren...

This seems like a good thing. Export sun power from sunny parts of the US to less sunny parts.

Yep. It’s why the Texas situation is so silly.

It's possible to still net lose money by exporting power. So much so that it might even still make sense to not do it even after a catastrophic failure every decade or two. The actual calculation will need to be done by those who have the figures and exact costs handy.

Who the hell was talking about the marginal profits when the clear alternative is ‘occasional catastrophe’.

What a ghoulish, inhumane, MBA (but i repeat myself) perspective.

> Who the hell was talking about the marginal profits when the clear alternative is ‘occasional catastrophe’.

You are the first to bring up 'marginal profits', so it seems like arguing against your own idea, or at best a self-imagined strawman.

Did you intend to reply to the post instead?

Though the closest in what Patrick wrote is still not this concept.

Why even go down the road of trying to rationalize catastrophes for millions of people if you don't even have any numbers or evidence?

Your post boils down to "maybe it's fine (based on nothing) for people to freeze or die in heat from a grid that's isolated for political reasons"

Did you misread my comment?

If not, what 'numbers or evidence' are you referring to?

The only thing I mentioned, costs and figures, are explicitly not known by me, so it seems bizarre to think I made judgements based on non existent knowledge.

The rest seems like your own rambling thoughts.

Did you misread my comment?

Texas has an isolated grid. They can't buy or export power. This causes grid overloads. People have ended up freezing and dying in heat waves due to power outages.

You said "maybe it ok, maybe it saves money even if there are catastrophes, but I don't even know what the money is like".

Why would you say that a terrible power grid induces crisis is ok at all, let alone when you don't even know how the money breaks down?

Thank you. This is precisely what I wanted to reply but didn’t trust myself last night to not get in trouble with dang.

He is the one who specifically brought up profits as a potential reason to accept catastrophe then got all offended and aggressive, name calling etc when people challenged this. Even going as far as to deny bringing profits into it THEN admitting he had no idea of the numbers but STILL doubling down on the ‘don’t believe your lying eyes about what I wrote’.

I genuinely questioned whether it was just me until I checked back in the thread this morning.

If I'm somehow being 'offended and aggressive' you are free to copy and paste whichever quote(s) from my previous comments to prove this?

So far as I can tell you have not done so, and, judging from appearances, the one writing offended and aggressive comments is not me.

You edited your posts, thank you for realising you'd gone too far.

You used the words 'edgy' and 'pathetic' amongst others. I'm sure the edit history is available to mods if you wanna go there.

I will no longer engage, you aren't doing it in good faith and you have lied several times on this thread alone.

Okay then show the proof?

Or at least type out the quoted sentences that you remember with 'edgy' and 'pathetic'? And then any passing reader can email dang to confirm if that's in a past comment revision, like you said?

If your unwilling to put in that basic effort after making such an accusation, then it seems self-defeating, plus no one would trust it.

I do sometimes use 'edgy', so maybe that is possible, but I really don't think I've ever called anyone 'pathetic', so this seems like a lame accusation.

(As a sidenote I don't even remember for my own comments made 48 hours ago how I edited them or what words changed after, so it's pretty astonishing that another user is keeping track.)

Well this seems a bit too snarky and not in good faith so I'm not going to substantially respond any further.

I wasn't too impressed with the last conversation I had with you, Cyberdildonics, and at best it seems as if your objecting to your own hasty paraphrase of my comment so I don't see how this could benefit any passing reader either.

All I see here is you avoiding backing up anything you are saying, even after you edited your comments.

You basically said 'what if it saves money' when discussing multiple state wide crises. Saying 'what if' isn't an argument in the first place, now you're avoiding confronting what you said completely.

Again, these are your own rambling paraphrases, of course I don't need to 'back up' another user's comments.

These were your own comments, there is nothing rambling here. It is A to B to C. If you could confront the topic instead of avoiding it with names and insults I think you would have already.

No, they are your comments, period. If you had included even a single exact quote from me, that would be different, going by HN norms.

Trying to argue around this fact is pretty odd and it's unclear what the intention is.

You are also free to contact any HN user you trust and confirm whether I'm making this up or not?

You are also free to contact any HN user you trust and confirm whether I'm making this up or not?

I don't understand your question at all. Making what up? Why are all your comments deflection? Why not quote yourself and explain what you were trying to say?

Again, if you are unsure about or believe another user is somehow being duplicitous about HN norms, rules, mod decisions, etc., then double check, such as by emailing dang.

Why won't you deal with what you originally said? All of your comments are trying to avoid your original comment.

It seems your already starting to forget prior comments in this chain?

I explicitly stated 3 days ago:

> Well this seems a bit too snarky and not in good faith so I'm not going to substantially respond any further.

See this link: https://news.ycombinator.com/item?id=37516711

Frankly, although I didn't want to bring it up previously lest it be too embarrassing, perhaps logging off and seeking some help would be the better choice, if you are genuinely forgetting how to check past HN comments.

EDIT: After thinking it over, I'm going to disengage here since I rather not risk the chance of inadvertently nudging someone further into a negative spiral.

I'm not going to substantially respond any further.

You didn't substantially respond at all.

No one is victimizing you by asking you to focus on what you originally. You originally said that maybe statewide energy crisis that directly result in deaths are fine because it might make sense financially without even having any numbers or actual information of any kind.

All you did after was try to be insulting and act like you are being victimized while avoiding anything about what you originally said.

Why not just deal with the current topic? Why not explain what you said? It's bizarre that you would rather thrash around and try to blame people for replying when you could just deal with the thread directly.

ERCOT, in fact, has several DC interconnects to other grids. The DC part is crucial: the grids do not have to be synchronized.

There are already DC ties to the other grids in Texas. They do buy and sell power from other regions. They just aren't particularly large ties, maybe capable of 2GW total?

You'd think so, but it often turns out that distribution is more expensive than inefficient local generation.[1]

We still want to do lots of distribution, but it'll be for reliability reasons rather than cost.

1: https://caseyhandmer.wordpress.com/2020/12/27/the-future-of-...

Does that still hold if various negative externalities are included in the comparison?

Not if local generation is fossil fuel with its unpriced externalities and shadow subsidies.

Bring on the sodium ion grid storage! Also, I'd think California has the terrain to do pumped hydro storage.

The article is about local solar vs distant solar.

Now that you pointed it, the patent-hell around molten sodium batteries should have ended already. Yet, I haven't hear about anybody doing anything with them. Is there some action happening?

I believe some new developments in that area are supposed to be hitting the market next year.

If you get 1MWh with 50% efficiency from a solar panel that's still better than burning 1MWh's worth of gas.

That entirely depends on how the panels are produced, no?

If you think gas is only 50% more polluting than making a solar panel, yeah.

I don't think that. Some gas and oil companies have, via their lobbies, produced content that implied this is true with articles that complain about the various processes over the lifetime of a solar panel that produce waste, but I think even they have refrained from making the claim that it's almost as bad as gas.

Over longer distances it is more economical to use hydrogen as intermediary for electricity transport, as it can be moved through pipelines and ships and takes its loss mostly in the conversion, not the distance moved. Other benefits are the ability to time shift loads and to use the hydrogen directly in industrial processes.

https://www.sciencedirect.com/science/article/pii/S2211467X2...

This is why the EU has plans to build out a large hydrogen transportation and storage grid.

https://www.h2inframap.eu/

> HVDC transmission losses are quoted at 3.5% per 1,000 km (620 mi)

https://en.wikipedia.org/wiki/High-voltage_direct_curren

> The Changji-Guquan ultra-high-voltage direct current (UHVDC) transmission line in China is the world’s first transmission line operating at 1,100kV voltage. The transmission line traverses for a total distance of 3,324km and is capable of transmitting up to 12GW of electricity.

https://www.nsenergybusiness.com/projects/changji-guquan-uhv...

https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity...

Losses can be compensated for with...more renewable generation.

(note that the above distance is roughly the distance across Europe east-west, distance across the US is a bit more, but you don't need to pull east coast generation all the way to west coast load centers or vice versa)

This is interesting. I guess I would've have expected more and more localized generation and coordination rather than long distance transmission and storage, but maybe it will be more of a combination of things.

Thanks for the insights, its not something I really thought of before.

Also, if you pay the cost of making the hydrogen, you can use it not only for transmission, but also for storage at both ends of the pipeline. This allows the pipeline to be operated at constant high load, allows smoothing of the production fluctuations, and smooths demand fluctuations too. Multiple bites from one apple.

The cost of a hydrogen pipeline is only slightly larger than that of a methane pipeline of the same BTU capacity, even though the energy value of a hydrogen molecule is considerably less than a methane molecule. That's because hydrogen has considerably lower viscosity, which reduces pumping costs.

Easy technical remedy -- add in storage on key nodes - sell it back to the grid in the evening or when its not high or bid back in on capacity markets.

Challenge is getting the pricing model correct for such ancillary grid benefits to make it worth it for developer to build.

It's like high frequency trading, except with the nation's power supply

Not quite but also, you know power trading markets have existed for a long time right and the lights stay on - probably a 99.9% uptime ;)

edit: Just re-read your comment I assumed you were implying high frequency trading as a bad thing - though it might have been to help non-energy people understand.

Well, you're not wrong! I understand power arbitrage is already a thing and for the most part it's OK. But once in a while you get situations like the crazy contracts in Texas a few years back. And I am a little concerned that if we create a large enough storage market controlled by a few big enough players, they could play financial games with a critical commodity, ie hoarding both generation and storage for peak resale value.

In both situations maybe there's an argument for market efficiencies and liquidity and such. But it scares me a little.

I am not a financial person (in the solar field, but not markets). I could totally be talking outta my ass!

There's always a risk of bad actors in any market. Hopefully we have learned and not forgotten the california energy crisis and Enron from the early 2000s. There are regulators who work on this though the market bad actors normally get caught a couple years after the fact. As long as the regulators keep catching them it seems likely that we won't have as many cheats.

The energy markets are significantly layered in power contracts that I would think it would be difficult for an energy storage provider to play that much of a position.

Well, there was this one energy trading company called Enron, and the power outages in California engineered to boost their profits. I'd say that some amount of weariness is justified in this case.

Do you have some idea on how to do storage cheap at scale? There is a lot of money for anyone who has an easy technical remedy.

https://www.tesla.com/megapack

https://electrek.co/2023/04/19/tesla-reports-massive-increas...

https://lorenz-g.github.io/tesla-megapack-tracker/

(on a smaller scale, to date, Tesla has deployed Powerwalls and Powerpacks at more than 50,000 sites worldwide; their Lathrop, CA facility is ramping to manufacture 40GWh/yr of capacity)

Dual feed power line, one for home electrics, one for immersion heater. Store excess renewably generated energy in household hot water tanks during the day, to be used in the evening in place of fossil-fuel generated supply, which also evens out load peaks as a side effect. This also works well with home solar.

I don’t understand. How do you convert hot water to electricity in the evening?

The Seebeck effect will definitely have less than 8% efficiency with 80C water. Perhaps GP means that the hot water will already be available to use for hygiene and laundry, which for those with an electric water heater, is a large portion of the household power draw.

I'm not sure if a household sized water tank-full could provide heat over the course of a cold night, and whether a heat exchanger for air heating or water pipes would be more efficient. I suppose it depends on the insulation and placement of the ducts and pipes and how much of the heat makes it to and through a wall.

I did some very crude calculations but assuming 50 gallons at 60C and 1000W energy loss per hour from a moderately insulated house on a 50F night, the full water heater could keep the house at 70F for 5.14 hours. Someone with more recent practical physics usage is welcome to check this figure.

You don't. It's stored energy. If your hot water is already heated, you save on the energy required to heat it in the evening.

just use it durectly fir showers and heating the house

That is a good idea for places that need heat.

Do the opposite (make lots of cold water) for places that need cooling. Am I missing something?

The energy difference between ambient-temp-to-frozen and ambient-temp to steam is much larger. I would think that this affects scalability.

I live in a city center that uses chilled water for some use cases, but it certainly does not seem scalable enough to be an "easy technical remedy" to the issues of distribution being expensive.

A home central A/C would use a volume of ice of maybe a cubic meter, if that. This doesn't seem excessive.

Not at all. Peak shaving with approaches like this is fairly common with utilities. Lots of them will give huge rebates on smart meters in exchange for this.

I think grid load management for water heaters is already fairly common. I've basic versions of the concept in use by a coop in South Carolina, and I can't imagine them being anywhere near the bleeding edge.

Two things: (1) Price signals have to be further clarified especially at a utility level for ancillary services (2) Battery system prices have been dropping quickly mainly as a function of Chinese manufacturers building out quickly e.g. CATL. Tesla is also helping.

Competition is already there - its next how do you deploy your development costs for winning those assets.

On the west coast, there are pumped hydro storage projects in Southern Oregon (500MW) the Columbia River (~1GW) , and Nevada (~1GW).

These are targeting 8-10 hours of sustained power when needed.

Solar pairs well with hydro - a reservoir is basically a big battery that you recharge by pumping water uphill.

Any idea what the efficiency loss might be?

I’m sure the loss is very high, but maybe could be overcome with ample solar inputs?

Modern pumped hydro has a round trip efficiency of around 80%, I understand.

My company is working on this. 50 kWh modules, similar cost/kWh to battery storage, but no lithium or rare earths. Optimized for daily 0-100% cycling.

http://www.vortical.io

I hope flywheel storage takes off (no pun intended) it seems such a logic solution when compared with water elevation or chemical solutions. Why hasn't it gone mainstream yet?

I remember being really hyped about flywheel energy storage... 20 years ago. I wonder if it has become more viable since then? And if so, what changed to improve viability?

https://beaconpower.com/carbon-fiber-flywheels/

These guys have two projects (check their operating plants) using flywheels. They're used for frequency regulation. About 20MW each.

They have become more viable thanks to higher efficiency motors/power components and magnetic bearings, among other things. The biggest drawback is still cost, which is what we're tackling.

In the past they have been made to work, but they were not much better than batteries. With the price of batteries dropping like a stone I suspect they are going to have an even harder time competing.

There are several differences from batteries. Generally the benefits are faster charge and discharge rates, unlimited cycles without degradation, no lithium or rare earths needed, and wider operating temperatures.

They are not good at long term storage though, as the self discharge rate is high. And historically they have been expensive.

Cost, mainly. Most flywheels use exotic components, expensive magnetic bearings, must work in a vacuum, etc.

Interesting! But 50kWh seems pretty small for (macro-) grid applications. How big are these units? Seems like most grid installations would want on the order of hundreds (~10MWh) to a few thousand (~100MWh) of these.

Or do you plan to focus more on microgrids?

The focus is on microgrids, but they're modular and can be installed below grade so you can add as many as needed. Approximately 2m diameter by 1m tall.

We're still working out costing, but it might even make sense for residential use to take advantage of time-of-use rates or energy arbitrage. Other applications are industrial processes that require high power for short periods.

Cool! I'll definitely be following your progress with interest :)

Hopefully constructive feedback: I would put that residential thing further down on your list. I think that stuff tends to be too complicated unless / until you can aggregate a lot of loads (eg. I think Tesla only recently recently started doing this stuff residentially. Probably awhile before you reach their scale...)

"Just do storage"... It's one of the hardest problems in the entire energy grid and on of the real sticking points of renewable energy, it's quite hard to store appreciable amounts of energy.

Pumped hydro is one of the better options but it has the ecological impact of just building new hydro power but less great economic impacts because the water level is less stable for people to live beside.

Ha yeah, this was my thought too. "Do storage" is the right idea, but there is no "just".

The numbers really aren’t that insane when you consider how quickly battery production has been ramping up. Nearly 100% of passenger cars going EV fairly quickly isn’t crazy looking at adoption curves. It’s likely those slow down soon, but continuing to build factories just as fast for grid storage is perfectly reasonable.

There’s over 280 million cars in the US, assuming on average that’s ~75kWh each we’re looking at ~21 tWh worth of battery storage. Meanwhile the average daily electricity use in the US is currently only 11 tWh. Of course that increases in a 100% EV world but EV’s are generally quite flexible demand.

PS: Solar power plants are often built to store ~50% of their daily output in batteries. It’s currently economically viable because that’s released at peak demand and thus peak prices, but with how quickly battery prices have been falling they will soon be viable even for normal nighttime prices.

Back feeding and metering all that power isn't exactly simple and it's also a big economic cost to just shove onto people in the form of increased battery wear and effectively reduced range since the most common trips begin early in the morning before renewables like solar come back online to produce the excess needed to recharge all the cars you've borrowed power from over night. Because of that cost that kind of distributed battery power is going to come out quite expensive unless you're just vastly underpaying for the depreciation of the battery like Uber does for it's drivers' cars wear and tear.

Another big thing is your 21 TWh number has huge flaws. That's fully draining everyone's batteries to provide the power and no one is going to accept that we want the cars because we need to go places. Next we're decades away from even getting close to full EV penetration. Even if we stop selling new ICE vehicles they're durable goods that people hold on to for a long time. It's the kind of 'Company/technology X takes over everything' assumption that so vastly inflates the valuations of tech companies all over the sector.

It was simply an order of magnitude comparison for manufacturing capacity. Slowing EV adoption at say 50% penetration would be beneficial for the grid as that excess capacity in mining and manufacturing could be used for grid batteries.

I doubt the the cheapest grid has anywhere close to 21 tWh as having more generation is more useful. Hydro is extremely flexible and reliable can fill in for a modest and predictable multi day shortfall. On the other hand if a power plant is down then batteries get extremely expensive.

That said, the cost of batteries isn’t simply a function of total capacity as unused capacity extends battery lifespan. The actual grid will take this into account which then impacts spot prices etc. Nobody operating grid scale batteries is going to 0% for wholesale prices of 5c/kWh but you bet your ass they’re going to 0% for 1$/kWh.

Just do batteries.

How many years do you have to go back before "just roll out lots of solar" was the silly hippy-dippy answer that all the sophisticated commenters who got their information via unofficial fossil fuel PR laughed at?

Remember when solar was the big problem that no one had a solution for? Turns out we did.

The future of energy is a lot of solar and a lot of batteries. Some other stuff will be involved but those two will do lots.

We're already at the point where new build pumped hydro doesn't make financial sense unless you have other needs for a big pile of water. Solar and batteries will beat it.

And pumped hydro is limited by geography. Unless the local landscape supports one lake above the other (for some suitable definition of "above") you can't build pumped hydro at any significant scale.

You can build them all over the mountains but it involves flooding new valleys with the associated cost both economic from displacing the existing people and destroying the ecosystem in that valley.

Why storage rather than using when available, eg running fridges/freezers/Aircon slightly cooler, water heaters hotter, charging cars, running the washing machine / dryer.

Industrially smelting aluminium, making hydrogen, heating water, desalination.

Not that I'm saying storage shouldn't be part of the mix.

The technical term for long-distance power delivery is "transmission". Distribution refers to getting the power from the local substation to the individual homes and businesses.

I love love love gridstatus! Both the website and the open source library. Thank you for your work!

Oh wow, gridstatus is super cool!

I noticed that you have a page on records that have been set. It looks like Ercot released this data today that might be of interest: https://www.ercot.com/news/release/2023-09-14-ercot-provides...

I’m curious why there appears to be a pretty significant delta between their data and yours.

Also, if you’re open to suggestions, I had trouble finding the pricing for gridstatus. Entirely possible I was missing something obvious, but I wanted to see how much it might cost to get the long term Ercot generation-by-source dataset and couldn’t seem to get a clear answer.

Regardless, building things like this takes a ton of effort, and I appreciate all you’re doing. Keep up the great work!

we report the instantaneous load records while that page is reporting the hourly average. I wouldn’t say the results are that different. They point to about the same times even if numbers have a small delta.

My focus right now is to make this data more available and easier to use. Haven’t done much to monetize yet. If you just want that data source, happy to get it to you for free. Shoot me an email at max@gridstatus.io or sign up for a free api key and grab it from the site

Hope it's cool for me to plug this here -- I'm one of the cofounders of a YC-backed startup working on robots that build large-scale solar farms!

We basically stick a bunch of industrial robot arms in a shipping container and use them to build solar fields out in the middle of the desert. https://chargerobotics.com/ (we have an open software engineer role for the factory, email in my profile if you want to chat! team is currently 7 people)

Since you work professionally with robot arms...

I've always thought that it would be cool to run a robot arm museum, showcasing industrial robot arms from different periods - 1960s, 1970s, 1980s, 1990s, etc. As far as I can tell the first one was Unimate in 1961: https://en.wikipedia.org/wiki/Unimate

But... I don't have a feel for how many of these things actually exist out there. Do collections already exist? What happens to a robot arm once it becomes obsolete?

This sounds like something lcamtuf might be interested in…

Older and prototype arms are sadly often scrapped past a certain point, there's just limited use for an ancient arm with it's associated ancient control systems (often a bigger issue to keep running than the actual arms as you're dealing with real time operating systems that are tricky to run outside of their original equipment.

Cool idea!

I don't know if this message is better suited for you or dang, but the capitalization of your hiring posts here has always been a little off:

"Charge Robotics (YC S21) is hiring meches to build robots that build solar farms"

Mechanical engineers would be better shortened to MechEs instead of meches, IMO.

Haha, thank you, I am the one who was posting those. Will fix it when we are hiring MechEs again!

Hiring mechs to build robots does sound very Von Neumann :-)

How do you plug that into the grid?

This is the hard part of that problem. You can’t just connect 100MW onto the grid. It’s actually a problem in many countries that invested in solar subsidy programs, had massive rollout of solar and were then had a grid that could not handle the huge load of electricity at peak sun times, causing them to leave entire farms disconnected or only partially connected.

Neat! Don’t the arms need to move around though?

They do. It's a very special shipping container...

Solar energy plants in the desert, including the transmission lines needed to get it to where it's usable, come at a cost to the ecosystems they disrupt.

We tend to think of the desert as a lifeless wasteland, but that's far from the truth. Visit Death Valley National Park for example and see the marvelous diversity and beauty of life there, especially during a superbloom.

Solar power plants in the Mojave desert threaten wildlife like the Desert Tortoise by reducing their natural range and plowing over the desert habitat.

Rooftop, parking lot, etc. solar makes much better sense by utilizing already disturbed land nearer to where the power will be used thereby reducing transmission costs and the treat to biodiversity. A major downside (from one perspective) would be that rooftop solar installers out-compete the developers of desert power plants.

Rooftop solar is more expensive than people think. You need to attach the solar panel to the roof, and roofs really, really want to leak. You also need to change all of this every 15-25 years when the roof needs a new cover.

Granted the are costs that are often overlooked but that can also be mitigated by choosing installers with a good track record and offer a good warranty on their work, not whoever shows up on your doorstep, and by investing in better roofing materials.

The solar panels should still be productive after 25-30 years even if they're less efficient, and they should have paid for themselves by then. If you're like me, at installation time, the roof was overdue for maintenance anyway.

It's very unlikely for a solar company, whether an installer or manufacturer, to last 25 or 30 years. I worked in equipment sales and our suppliers would routinely go out of business or be on the verge of bankruptcy. We'd advertise warranty insurance and reinsurance because it was assumed that the company wouldn't be there that long from now.

If you just have modules (the panels themselves) on the roof that long you'd probably be okay, but if you have microinverters or power optimizers under them, those power electronics have a finite lifespan and will eventually die. Or if a single module wired in series goes bad, you'd still have roof work to do.

It's not just install and forget. It's install and pray you don't have to do too much work too soon...

(Edit: Ideally, these systems would pay for themselves in a few years. As long as that happens before they die, you'd still come out ahead. But that's not always the case. My last company got sued because the stuff we made kept failing -- it was in the news, so no company secrets there. One of our major installers also went bankrupt. Depending on who you ask, our equipment may or may not have been at fault.)

Yeah, this is one of the worst aspects of residential solar, IMO. Workmanship and labor warranties are fragile at best, and the cost to do seemingly basic things is not insignificant.

Lose a couple of panels near the middle of an array due to a power optimizer after a few years and you might end up debating whether it is even worth fixing it. That isn't so bad in itself, but it also might completely mess up your financial return estimates.

Yeah. One of the companies I worked for actually sold mostly to the DIY crowd, and I've done a few installs myself. It's not very hard -- most of it just plug and play, and even the roof entry points can be easy if you have the right flashings. (You would need an electrician to do the final approval and connection in many jurisdictions, though.)

That is to say, it might not be a bad idea to pick up a few spares when you buy a system, and learn to replace broken modules or power electronics on the roof yourself if you need to and the company no longer exists. Just a thought.

Where would one learn this knowledge without joining the trade?

Glad you asked! There's a few ways I know... mix and match as you see fit!

1) 4-6 hours, free: Volunteer with Grid Alternatives (https://gridalternatives.org/get-involved/volunteer), a nationwide (well, several states) nonprofit that donates and installs surplus solar for needy families. You get hands-on installation experience with a crew.

2) 2-3 hours, free: Self-study materials online like this guide from my former employer: https://unboundsolar.com/blog/step-by-step-diy-solar-install... (I didn't write this, and the company changed owners after I left... not sure how it is these days) or if you prefer a community wiki: https://www.appropedia.org/How_to_install_a_photovoltaic_sys... . And of course these days there's probably a bunch of stuff on YouTube too.

3) 18-40 hours, few hundred dollars: A NABCEP prep course (https://coursecatalog.nabcep.org/exam-courses) is probably the best way short of an apprenticeship to learn to do this the right way. The North American Board of Certified Energy Practitioners gives (optional but thorough and helpful) solar installation and design certifications. Anyone can take the courses, even if you don't want to get the cert. (I did that just for my own knowledge, while working as a web dev for a solar company). Make sure whichever class you take has a mix of both theory and hands-on practice with real equipment.

4) A few months, more expensive: See if your local university or community college has cheap or auditable (drop in for no credit) courses you can take. Mine had environmental engineering and sustainability courses that included hands-on solar design and installs.

Please note that whatever you choose, in most areas it will NOT be legal to finish your install without an electrician (assuming a grid-tied system connected to your local power utility, vs a standalone battery-backed up off-grid system). You can do most of the work yourself though (great excuse for a pizza party on the roof with friends) but don't actually hook it up / turn it on without a proper permit and electrician inspection. Still, this saves a bunch of money over a fully professional install, and this way you also intimately know the equipment and labor standards better.

Edit: Oh, by the way, some solar resellers (like my former employer above) will help you design the equipment and sell it/ship it to you direct, making it that much easier (you don't have to worry about all the electrical details as much, unless you like that sort of thing... you just have to install what they give you).

I think these days there are also some online design sites (OpenSolar, Helioscope, Aurora, SolarEdge, etc.), but I think those are tailored towards industry professionals and not homeowners. Still, they might be helpful if you want to sign up and play around with a mock roof layout with real equipment connections.

Climate change also disrupt ecosystems. Tradeoffs have to be made, and blocking everything doesn't mean things stay the way they are. It means continued CO2 emissions, higher energy costs and housing shortage. Rooftop solar, while a good thing, is more expensive to install and not enough to replace fossil fuels.

For what it's worth, I agree that trade offs need to be made, like lithium mining and nuclear power. Desert solar plants looks like a painless win on the surface, but they don't hold up to scrutiny.

> Rooftop, parking lot, etc. solar makes much better sense by utilizing already disturbed land

Citizens For Responsible Solar is a front used by fossil fuel companies to block solar farms and they object to every single solar farm claiming it should be on the roof. They object to rooftop solar and claim it should be on another roof, etc.

Land use by solar is not a primary concern, there is more land wasted on gold courses than would be required to power the country.

This objection is shared by many local environmental groups, not just bad faith astroturfers.

https://www.lasvegassun.com/news/2019/jun/18/massive-gemini-...

You're being downvoted as it sounds like a concern troll, similar to wind turbines and birds but...

There is actually less and less reason to site solar in deserts.

As solar has dropped in price, lots of things we used to do to optimise the expensive solar no longer make sense.

We used to build trackers that would point the cells directly at the sun all day, now that extra complexity can be replaced with just buying more panels.

Similarly, long transmission lines out to deserts can be replaced by more solar spread everywhere that we need it.

But to close, I want to reiterate that if you're reading some article about solar panels destroying the desert it's almost certainly bad-faith bullshit, so don't worry too much about it.

There are people making bad faith arguments for sure, but they're piggybacking on the real concerns of local environmental groups.

https://www.lasvegassun.com/news/2019/jun/18/massive-gemini-...

Automated solar deployment via robots... I do the same thing in Factorio

Just wait for the nuclear update!

This is really cool! If I knew Python I'd totally apply. What a fun project.

It’s too bad they wouldn’t let you learn on the job!

I don't blame them. With tens of thousands of qualified ex-FANGers to choose from right now, it's a great time to find new talent! I'm just a random nobody who makes websites here and there lol. I'm sure they can find super qualified robotics people.

For me, your site says "renewablesby", instead of "renewables by" https://ibb.co/vqxfvB9

I wish home solar was more ... trustworthy?

I've looked into having rooftop solar installed a number of times, and every time I've walked away with the feeling that I don't know enough to know what to watch out for, and that there was a high probability that any company I dealt with would be trying to take advantage of my ignorance.

100% true. And you are right. They have the same vibe as car mechanics.

Also Panels, inverters and batteries are all quite different and have varied pros and cons and installers are typically getting kick backs from specific suppliers so their advice is not impartial

If you have a backyard (or a balcony) I'd start with a single solar panel and "portable solar generator" off of Amazon. For about $500 (admittedly terrible $/kWh) I felt like I got a much better intuition about things like "solar panels generate ~no power in partial shade" and "power output from a solar panel changes from month to month" which can help you in your decision-making.

It's not obvious to me that rooftop solar panels will still pay for themselves (in the past there were subsidized rates that made the math work better) but being able to run off batteries+solar "microgrid" in a power outage for a few hours is a quality-of-life improvement that I'd consider for the right price. (There's some of this in corporate offices, luxury apartments, etc.)

During the pandemic I built a number of simple indoor solar systems, setting panels in the lower part of my windows (I keep the shades open at the top) and hooking up to either a homegrown controller/battery/inverter system or a jackery.

The jackery is roughly 30% more expensive but feels a lot less fragile than my homemade stuff, and I've moved all my device charging (tablet/phone/power tool battery) charging over to these systems.

It was a fun project! Cabling is always the part that sneaks up on you so make sure to plan out the cabling / what plug types you want / crimp or buy / etc. ahead of time.

Yeah, and the cost gap between home solar and grid simply means that the firms are probably pocketing the federal subsidy indirectly.

There seems to be some DIY advertised costs that might be better. Really, this is mounting stuff on a roof and wiring it to your garage. While there is code and best practices, this is not disassembly of your car's transmission.

I'm hoping DIY practices and experience disseminates over the next decade, as well as cheap-good perovskite+silicon panels and sodium ion/sulfur/solid state battery storage.

>I'm hoping DIY practices and experience disseminates over the next decade

I am not affiliated with the below, but saw DIY kits - your comment reminded me others might have experience. One quote that is interesting "With the current tax incentives to go solar, our DIY solar customer’s average ROI is less than 5 years."

https://www.solarwholesale.com/diy-kits/

I hope home solar turns into a normal trade. Then it will be done by regular contractors. No different than getting new roof or water heater installed.

I also think there is a place for solar company that ignores the hard sale and leases. Even better if they focus on efficiency and getting the installation price down. Franchised or training companies would also work.

As prices drop, it becomes possible to pay immediately. Or get a small loan. I wish they would ban solar leases.

100% true - find a friend or good online resource. A lot of the workforce is just repackaged contractors. There are many good ones -- but their model is still built on needing to sell more solar and you need to know what you are buying.

You could try speaking with a supplier like AltE Store directly. They'll help you design a system for your use case and you can get a local installer to handle the installation, or DIY. I'm not clear on how the subsidies work with this approach, though, and whether you'd have to go through a local dealer / installer to qualify.

I agree completely, and the best antidote is getting a little knowledge about how home solar works. Something that should be well-in-reach of most of the HN crowd.

A typical grid-tied home solar system has 3 big areas of component costs:

1. The actual solar panels.

2. The thing that mounts the solar panels in place (called racking)

3. The things that turn the solar panel's electricity into electricity that can be used in your home and by the grid. Typically inverters and wiring.

The good news is that you can price this all out yourself, to get an idea of what your system SHOULD actually cost. Then you could theoretically do it yourself, or be a more informed consumer when shopping around to have someone do it for you.

I haven't pulled the trigger yet, but I've been planning, revising and tracking prices on a DIY install for the past couple years.

Here are some of the resources I like:

1: Unbound Solar is a good resource for ready-to-install DIY kits. Their kits are a good resource for "this just works" - and you can then price out individual components as-needed. - https://unboundsolar.com/shop/solar-kits?product-category=gr...

2: For buying actual panels, I like A1 solar. They seem to have the best selection/pricing I've found: https://a1solarstore.com/

3: OpenSolar is a free tool designed for solar installers, but available to DIY'ers. It lets you specify your panels, racking, inverters etc., and then lay them out no your roof or the ground. https://www.opensolar.com/ - It's very likely the tool that the contractors you're getting bids from are using.

The last bit of info I'll share is that in general, microinverters don't make sense from a cost/benefit standpoint. Panels have gotten really cheap, microinverters haven't. You're probably better off adding more panels with a traditional inverter system vs. paying for microinverters to get marginal efficiency gains from a smaller number of panels.

I've did this all and currently installing a ~29kWp solar roof myself here in Switzerland. I will pay less than one third of the costs as when it gets installed via a company.

As far as I can tell I didn't get screwed using https://solaroptimum.com/

One thing I'll tell you: don't listen to anyone wanting to come and inspect and propose stuff. It's a huge salesman heavy market, so you have to research it or just ask someone that has it already.

The only thing the installers have to figure out is how to wire up the panels with your inverter in the right ratio, and if your roof can hold the panels you want. The rest you pick and they do.

Don't get an offgrid inverter, hybrid grid-tied inverter all the way. Even if you live in the sticks with no grid, just get a hybrid one.

Also, don't worry if your batteries will last the night or cloudy days or whatever. Just make sure you have enough to handle your load if it goes down, the rest works on its own and the inverter just blends your solar with whatever it needs from the grid.

> Don't get an offgrid inverter, hybrid grid-tied inverter all the way. Even if you live in the sticks with no grid, just get a hybrid one.

Would you please expand on why a hybrid inverter is better even if you're not going to grid-tie it?

Main reason being it's just easier and narrows down the choice of picking an inverter, which causes a lot of people to get stuck trying to find the right one that fits their "scenario" perfectly.

But also hybrid does everything you need and the cost savings of something else is marginal from what I've seen. It's an "all in one" that I believe is a good one size fits all for 99% of the houses out there. Every house should have a 5/10kw inverter installed by default with a corresponding set of solar and battery pack. I.e.

5kw solar panels, 5kw inverter, 5kwh battery bank. Or 10 or 15. It acts as a giant ups, let's you shift some power, and you can gradually reduce your grid reliance to almoat 0 by adding more batteries, all while staying on the grid just in case.

Yesterday I finished a DIY rooftop installation. I went DIY partly because I shared your concern, and mostly because I thought it would be fun. I have thoughts.

My quick take is that there is enough competition to ensure reasonable prices for solar equipment (panels, racking, electronics, etc.). However, a lot of manual labor goes into a rooftop installation that's comparable to other trades like plumbing, electric, roofing, construction, etc., which means that if your local cost of living is high, then the labor cost will be high as well. Until we have robot labor, I accept that other people need to put food on their tables as well, so I don't think that a lot of overhead in a solar project's cost beyond the materials is necessarily evidence of exploitation.

This means that you can online-shop and build a cheap system (I'm sure under $2 per watt is easy). But it needs to be shipped to you, lifted onto the roof, mounted, and finally wired to your grid. All that is pure labor. I did everything except the high-voltage wiring and the conduit runs, and I bet a competent version of me could have done everything I did in three 10-hour days (it actually took me twice that). Where I live, California Bay Area, you can't get any tradesperson out of bed for less than $100/hour, so that's at least $3,000 in labor. The electrician, permitting, and re-patching the roof around the new mounts added another $4,500 -- again, mostly labor and/or bureaucracy.

That makes about $7,500 to install maybe $10,000 of equipment. I avoided about $3,000 in labor costs by spending at least 60 hours of my own amateur time, including mistakes, worrying, second-guessing myself, and other activities that a professional wouldn't have done.

I learned a lot. I understand the difference between microinverters and regular ones; I know more about split-phase residential electricity in the US; I appreciate how a system design trades off cost and efficiency for issues like "clipping" when an inverter can't handle the full output of a PV panel; and I know way more than I ever wanted to know about the foam, insulation, tar, gravel, and wood that make up my roof.

In retrospect, I'm glad I did the project because of the knowledge gained, and because I now have even more respect for the skills and effort that are needed to put solar on a home's roof. But would I do it again? Probably not; I'd rather have paid the extra few grand to have someone do it for me while I stayed cocooned in my office, writing code.

TL;DR: profit is being made in residential solar, but I believe most of it goes to honest labor.

Surprised by your labor estimate.

Here in the Netherlands, the norm is that it's a single day of work by a crew of two. That includes everything you described: rails, installation, repatching, wiring, inverter, basically the entire package.

I said "a competent version of me," not two solar-installation professionals. :)

If my estimate was 30 hours, and your estimate is 2 x 10 hours (assuming 10-hour days), then we're mostly in agreement.

The downward trajectories are so strong now, it soon won't make any sense more to do these small deployments anyway.

> Solar deployment is now running at about $500 billion per year, which means that about 0.5% of global GDP is being spent on solar deployment. This figure is up an improbable 43% Y/Y

What a mind boggling relative and absolute increase.

This is caused by the cost of solar declining 89% in the last decade [1]. Batteries are next [2]. Which leads us to solar and batteries powering the world [3]. Extrapolate exponential growth of generation and storage, not linear. There is >1TW of generation and hundreds of GWs of renewables and storage (respectively) in aggregate across all US grid operator queues, for example [4]. Similar story in China [5].

(obvs we have a long way to go, just need to push the pedal to the floor; enough sunlight falls on the Earth in 2 minutes to power humanity for a year [6], and space is not a concern [7] [8])

[1] https://ourworldindata.org/grapher/solar-pv-prices

[2] https://ourworldindata.org/battery-price-decline

[3] https://news.ycombinator.com/item?id=37435387 ("Solar and batteries are going to win, and our thinking needs to adjust")

[4] https://www.pv-tech.org/nearly-1tw-of-renewables-in-us-inter... ("Nearly 1TW of renewables in US interconnection queues as wait times continue to grow)

[5] https://www.theguardian.com/world/2023/jun/29/china-wind-sol... ("China is set to double its capacity and produce 1,200 gigawatts of energy through wind and solar power by 2025, reaching its 2030 goal five years ahead of time; ...as of the first quarter of the year, China’s utility-scale solar capacity has reached 228GW, more than that of the rest of the world combined.")

[6] https://www.ku.ac.ae/two-minutes-of-sun-enough-to-power-a-ye...

[7] https://landartgenerator.org/blagi/archives/77565 ("Land and Ocean Areas to Support a 100% Renewable Energy, Zero-Emissions, Regenerative Global Economy")

[8] https://news.ycombinator.com/item?id=37492062 ("Declining populations free up ag land for solar in densely populated countries")

Holy cow that lithium price graph is astounding! It's a log plot that looks like a linear decline in price. It's like Moore's law for lithium..

Moore’s Law is a special case of the more general “Law of Accelerating Returns.”

> In my view, it is one manifestation (among many) of the exponential growth of the evolutionary process that is technology.

https://www.thekurzweillibrary.com/the-law-of-accelerating-r...

Great charts. I hope they update them for current years soon. I'm not sure if: the trend continued (because of technologic progress and the learning curve), the trend reversed (because of supply chain issues), or stayed the same because of the combined effects of those 2.

Very informative. Note from your 4th link I wasn't previously aware what "interconnection queues" were. This is a good overview: https://emp.lbl.gov/queues.

Importantly, though, only a small percentage of that capacity "in queue" will actually get built. From your link:

> Much of this proposed capacity will ultimately not be built, however, with only 23% of projects seeking connection from 2000 to 2016 having subsequently been built based on a LBNL analysis of a subset of queues. Only ISO-NE and ERCOT exceeded 30% completion rates, with CAISO performing the worst at 13%.

Good callout wrt queue completion ratios. Unfortunately, there aren't many comparable leading indicators of future generation to rely on (maybe EIA's 860M survey? [1] [2], but it only gives you a short look into the future). Plans are plans until steel is in the ground and glass is getting racked. Open to other suggestions if it improves modeling and forecasting.

Regardless, the amount of renewables and batteries coming online (at least in the US) can't be overstated [3].

[1] https://www.eia.gov/electricity/data/eia860m/

[2] https://www.eia.gov/electricity/monthly/

[3] https://www.eia.gov/electricity/monthly/images/figure_6_01_c...

> Regardless, the amount of renewables and batteries coming online (at least in the US) can't be overstated [3].

> [3] https://www.eia.gov/electricity/monthly/images/figure_6_01_c...

The "Other" generating unit type on that map is all over CA and TX. Looking at the source data for the map [1], it's mostly batteries. I'm surprised they didn't break those out as their own category.

1. https://www.eia.gov/electricity/data/eia860m/

No, not mind-boggling at all. It's about a tenth of what is required to meet governments' signed-up-for targets for limiting global average temperature rise to 1.5 degrees above pre-industrial.

For reference about 2% of global GDP is spent on new fossil fuel mining and drilling investment, and another 2-4% on the fuels (including refining).

A 10x increase is about 6 years at the current growth rate. That's mind-boggling.

It can also be not enough. They're not mutually exclusive.

I would have expected the ratio of $ spent on new fossil fuels vs. new solar to be a lot higher than 4. My mind is quite boggled.

The figure I like to quote is that we need 2 to 5% of GDP spend per year to get to net zero by 2050.

We already pretty much passed 1.5C anyway, right?

Yes. If we were spending 5% of global GDP on Solar and Wind now, there'd be a slim chance. Scaling up to that in six years, as a sibling comment claims, is way too late.

Jevon's paradox is one hell of a thing. When you suddenly make something very cheap, a lot of people suddenly start wanting a lot of it.

What you are seeing is basically the consequence of solar changing from not the cheapest power source available into the cheapest power source available. Immediately, everybody that would invest into something else changed into solar.

If Solar provides up to 90% of CA’s peak capacity, why is electricity here so monstrously expensive? Shouldn’t it be nearly the lowest cost because there is no need to pay for fuel?

1. How much "area under the curve" comes from _up to_ 90% of _peak capacity_. If it read "50% of annual consumption", I might be more inclined to ask your same question.

2. It doesn't necessarily follow that free fuel == cheaper power. I'm not at all familiar, but I imagine building, operating, and maintaining a solar plant could be expensive, perhaps even more expensive than a coal plant, for all I know.

The best way to measure this is from the CO2 emissions estimates. These fell by about 23% from 2018 to 2023[1], implying that renewables have displaced about one quarter of fossil fuel inputs. However, it should be noted that nobody really knows the true denominator of energy demand, because distributed small-scale solar production adds up to an unknown quantity.

In the spring and summer seasons California routinely hits over 100% of demand generated from renewables at some point in a given month. CAISO, which does not cover the entire state, says that in June about 47% came from renewables. Last June it was only 37%.

1: http://www.caiso.com/Documents/GreenhouseGasEmissions-Tracki...

Operating a solar plant is very cheap.

the other 10% …

Yea if you look at your bill a lot of the cost is not in generation, it’s in transmission. We’re paying for the grid mostly, upkeep and PGE/SCE profits.

Last I checked my mother's bill in the SF-Bay, her price for each, transmission and generation, was higher than my total delivered price in Oregon.

The most cost-effective form of solar power is utility scale solar farms. In 2012 California was installing those faster than it did last year. Hover over the chart in this article to see the year-over-year changes:

https://www.canarymedia.com/articles/solar/chart-whos-the-le...

As toomuchtodo mentioned in another comment [1], the cost of solar declined 89% in the past decade. California's installed base is weighted toward older, more expensive solar power installations because it started installing solar power sooner and more rapidly than other states. That's compounded by California's slowdown in utility scale solar farms added in recent years. Texas is about to surpass California on installed solar farm capacity and Texas's solar generation will be cheaper because those farms have been built more recently with lower cost solar hardware.

[1] https://news.ycombinator.com/item?id=37502924

I would appreciate data to the contrary, but the accounting in your first claim doesn't seem right to me. Behind the meter rooftop solar should be the most cost-effective because no new distribution is required nor is any land use change required.

The National Renewable Energy Laboratory has charts and reports showing US system prices per installed watt for residential solar and utility scale solar with single axis sun tracking:

https://www.nrel.gov/solar/market-research-analysis/solar-in...

In 2010, the cost-per-watt was a little more than 2 dollars higher for residential solar than for utility scale solar ($8.70 vs $6.54). In 2022, residential was still a little more than 2 dollars higher ($3.16 vs $1.06), but since system costs have plummeted, that means the ratio now favors utility scale installations much more dramatically.

You can see in the charts that "Soft Costs - Other" remains persistently high for residential solar. That includes things like permitting and inspection. A 100 megawatt solar farm requires permitting and inspection too, but it's much less cost than the 10,000 permits and inspections required for equivalent capacity distributed across residential rooftops. The other big difference evident from 2010 to 2022 is that residential solar inverter costs are still significant whereas the inverter costs have become practically invisible in 2022 for large solar farms. More aggressive price competition and increasing unit capacity have proportionally lowered the inverter costs much more for large solar farms.

The cost per megawatt hour generated is actually even more imbalanced in favor of large solar farms than these cost-per-watt charts show. You can't use solar tracking on rooftops. Solar farms with single axis tracking to follow the sun's position generate more energy per year than equivalent wattage installed in fixed positions on rooftops. Average rooftop systems are also less frequently cleaned than ground level solar farms. Not only does rooftop solar cost 3 times as much per installed watt, it also generates maybe 30% less energy per installed watt per year.

Thanks for the link.

Two issues I see missing from NREL's analysis: land use and distribution.

I don't see a cost attributed to land in there. It's free for residential because it's already put to use, but not so for utility-scale and probably hard to estimate broadly. Environmental impacts of that land use should also be accounted for in addition to direct land acquisition cost and/or leasing. Solar generation does not have land impacts when placed on a roof. That land is already "disrupted" and therefore allocated for human use.

Either way, labor is now the dominant piece of the cost for residential, and it's obvious that one-off small jobs in high-price metros are more expensive than a crew operating in rural areas. An accounting looking strictly and materials + labor is going to heavily favor utilities, but it doesn't capture the full picture.

Last I checked in West Texas, the cost of land was < 2% of the total cost of installing a solar field. This was for land at $1200/acre.

Yes, you cherry-picked an under-regulated market with cheap land. Not to mention that cheap land is usually further from metro areas and thus requires more distribution costs. Either way, as I mentioned land acquisition cost does not fully encapsulate the environmental costs of covering large tracts of natural land with panels.

I looked in online real estate sites recently and found $1000/acre land within a few hours of NY City. Land is quite cheap.

I hope you are spending your time attacking farming, which uses orders of magnitude more land than PV (and will even in a PV-powered world) and delivers orders of magnitude less economic value per unit of land.

Why is it so expensive? 3 words: Investor Owned Utilities. And two more for good measure: Regulatory Capture.

You'll have to use more words to explain why other Investor Owned Utilities have power at 1/3 the cost. Not really a unique differentiator.

Because CPUC allows a much higher return on capital in California.

Wholesale electricity prices are based on the marginal cost of electrical generation. As a result, wholesale costs will generally be driven by the cost of natural gas generation.

> > why is electricity here so monstrously expensive?

This is in line with why are we replacing fossil fuels with solar.

It was never a quality of life play, it's some sort of altruistic effort / dumbness deciding to be the suckers kind of thing.

California for sure cares about them Californians who'd be alive 150 years from now more than those who are alive right now. Actually not even that, given that the atmosphere is one for everybody, they care more about Indians and Chinese who'd be alive 150 years from now than Californians who struggle and are 'alive' right now.

> Actually not even that, given that the atmosphere is one for everybody, they care more about Indians and Chinese who'd be alive 150 years from now than Californians who struggle and are 'alive' right now

Given that the atmosphere is one for everybody, comparing by country does not make sense because some countries have more people than other countries.

> > comparing by country does not make sense

It makes sense to identify who are the fools and who are the wiseguys.

Like the solar panel industry which was jumpstarted with immense subsidies by Germany, EU and the US and now is 99% a Chinese industry manufacturing product. Amazing.

And EVs will be too, once the smoke clears we'll be lucky if we are left with just the brand and the cult of personality of Tesla, while everything else will be manufactured in China.

Chinese clean energy subisidies were over half a trillion dollars in 2022 alone.

Transmission, paying for PG&E starting wildfires and the resulting settlements, paying for living wages for folks working at PG&E living in monstrously expensive places, paying for debt and the rest of the power generation infrastructure.

The problem is actually battery storage. There's a great tiktok that breaks down the costs here: https://www.tiktok.com/@lthlnkso/video/7258394490145099050

Insightful video, thanks for sharing.

I use solar at home and the battery is actually the most expensive and least durable component of the system.

Also the battery disposal story is not great (at least at the moment).

They don’t mean 90% during peak demand. They mean at most solar makes up 90% of our generation. This would occur 11a-2p. Peak demand is 5-7 pm, and it’s twice as high as the midday load and it’s met by huge natural gas turbines that run a few hundred hours per year.

I don't recall the breakdown, but someone posted somewhere (so it must be true) that the overall distribution of PG&E was 49% nuclear.

Now, nuclear is not fossil fuel, but Lazard measures LCOE of nuclear as 6x more expensive than solar and wind. So that might be part of it.

Because you still have to pay for enough fossil fuel generators to power the grid AND the solar and wind subsidies, because the latter can't supply power all the time. If every solar setup had to provide guaranteed minimum power 24/7 for 30 days, then you'd see the true cost is much higher because they would need to directly pay for a mostly-idle power plant, instead of the very inefficient way we do now (brinkmanship of grid stability and occasional massive spikes in wholesale cost).

In WA we pay more for "fish mitigation" than all other hydro-related costs. I expect CA has similar money pits.

https://www.fisheries.noaa.gov/insight/barriers-fish-migrati...

It's almost as if everything on this earth is a reflection of Sun. We finally figured out how to harvest it at scale without depending on nature in the middle.

Heck, the next big revolution will probably be solar + agriculture dual land use, since you don't need all the sun's energy for plant growth during the day. It might even lead to higher yields because the solar panels might integrate led lighting for growing in the night.

So the plants get "saturated" and don't want more than a certain amount of light per hour?

Growing at night outdoors seems like the kind of light pollution that would harm something and anger someone, but not unlikely anyway...

Do we really need more yields? I thought we made enough food for everyone already and it's just distribution at this point?

Some specific crops grow better in the shade and the bonus is that they cool the air around them. That improves the efficiency of the solar panel. It's a win-win all around.

The one challenge is getting the mechanized equipment of industrial farming around the panels without damaging them. There are companies working on improving that too.

Some plants can indeed get saturated (they tend to tuck their leaves in past that point), but I could imagine more serious savings from the practice if the partial shading from solar installations reduces evaporation. In most places (particularly those where solar is most profitable) agriculture is limited by availability of water, so anything preventing evaporation is a potential boon.

Any increase in yield reduces the amount of land needed. I thought land use was the putative horror critics of solar were objecting to, so surely they'd want to cut down the much larger area used by farming?

A lot of plants outdoors are grown in partial shade via shade netting. In my head, it makes a lot of sense to supply some of that shade with solar panels. Likewise, it's a win because we "dual" use the same land surface area. We also probably save on water by not leaving so much of it to evaporate from the direct sunlight.

Maybe someone smarter or more knowledgeable can help out, but this strikes me as a very elegant solution.

Can an American explain to me why there are so many solar scams in the USA?

I'm about to bring my 20,000W rooftop array online. In my country I simply got quotes from local professionals and it was painless. I picked the best system that met my needs and they installed within weeks.

You know how haggling is accepted in some countries as part of doing business? In the US, small businesses scamming consumers if simply part of doing business. It's up to the consumer if they want to spend their time getting competing quotes or finding trusted referrals. But for a lot of people, a lot of the time, it's just easier to pay the premium even though you know you're getting ripped off. You'll find this in auto repair, landscaping, construction, plumbers and electricians, even web developers!

In the US, it is really hard to sell solar in a lot of places. This can be true even for houses where it would obviously be useful and even when incentives make it so obvious that anyone _should_ do it.

Companies minimize their sales cost by using the lowest cost, most effective salesmen that they can find and don't monitor them very much.

Perhaps unsurprisingly, the ones that you hear from the most are the ones that you almost certainly shouldn't do business with.

I feel like there should be some term for this kind of market, where the worst of the worst natural rise to the top for periods of time.

Module prices are now $0.130/W - $0.151/W: https://www.pv-magazine.com/2023/09/08/china-solar-module-pr...

This is less than the 2030 projections of $0.17/W for modules: https://www.energy.gov/eere/solar/articles/2030-solar-cost-t...

Related, China adds enough new solar and wind every year to cover the total electricity use of many major economies such as Australia and the UK: https://www.sustainabilitybynumbers.com/p/china-renewables-2...

The data is whatever the data is, but measuring in nominal dollars sure seems like the wrong way to approach this. Did 40% more gigawatts get deployed or did the cost of installation labor account for some/most/all of that increase?

Hourly wages for solar farm construction labor have gone up, but more efficient installation processes and lower cost hardware have compensated for that increase.

The International Renewable Energy Agency says that 191 GW of solar capacity were installed in 2022:

https://www.pv-magazine.com/2023/03/22/new-global-solar-capa...

Wood Mackenzie estimates that 270 GW of solar will be installed this year:

https://electrek.co/2023/08/03/a-record-270-gw-of-solar-is-p...

270/191 = 1.41, or a 41% increase in installed capacity this year.

A nice surprise. Thanks for the links!

I wish it were ear when an article talks about GW of solar.

Like is that averaged across the whole year? Days only or night too? Maybe it's peak output? Who knows.

These numbers refer to peak solar panel output under standardized test conditions. The annual output of an installed solar panel depends on how sunny a region is, whether or not the panel tracks the sun, ambient temperature, how much soiling is present on the front glass, and other factors.

Utility scale PV solar farms in the US had an average capacity factor of 24.8% last year:

https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...

These solar farms totaled 64.219 gigawatts of peak capacity and generated 139,670 gigawatt-hours of energy, equivalent to running at peak output for 24.8% of the year.

The International Renewable Energy Agency also collates statistics about global electricity generation from renewable energy sources. These numbers take longer to publish than the capacity numbers, since they're more complicated to gather, but you can see the latest update here with numbers for 2021:

"Renewable energy highlights, 3 July 2023"

https://mc-cd8320d4-36a1-40ac-83cc-3389-cdn-endpoint.azureed...

In 2021, global solar electricity output increased by almost 23%, growing by 191 terawatt hours.

The full 440 page IRENA report with stats on both peak capacity and actual production through 2021 is available here:

https://www.irena.org/Publications/2023/Jul/Renewable-energy...

> If one takes at face value the estimate that the world will deploy 300–400 GW of solar in 2023 (IEA), and that 1 MW of solar =~ 5 acres, we're deploying roughly 3–4 acres of solar per minute.

The thing about solar is location, location, and location. The annual average GHI in the Mojave is over 6 kWh/m2/day while in Alaska it's under 3. Interestingly, Germany, who funded a big push into Solar, has the solar resource of Alaska.

So you can't derive the area or cost from a unidimensional installation chart.

Youtube's premier economist/deadpan comedian, Patrick Boyle had an interesting video on 'Electrify Everything' a few weeks ago. It could be seen as pessimistic but I think its a fairly realistic view of the costs involved in moving away from gas and oil for transportation and household & industrial energy demand. In particular, grid capacity is going to have to at least double, if not triple. Perhaps he underestimates a push towards more efficiency (i.e. a one-to-one replacement of relatively inefficient fossil fuel-powered devices in terms of energy usage is an overestimate of demand, I think), but there's little doubt that the price of grid improvements and battery storage is going to at least match the costs of the primary wind/solar energy generation systems:

https://youtu.be/w4WfbqE5elk

Technologically a complete transition to renewables is entirely plausible, but it's a mistake to try to play down the scale of effort needed - but this doesn't mean it's not possible. Look at the > $10 trillion in global oil infrastructure for comparison - offshore oil rigs, continent-spanning pipelines, gargantuan refinery complexes, a huge fleet of ocean-travelling oil & LNG tankers, etc. Of course replacing all that is going to be a major effort, requiring a significant diversion of civilizational resources to the task.

for transportation, there is one kind of out: synthetic fuel. It's 3x the cost of normal fuel at the moment, but in exchange you get a very dense form of energy storage that can be used with a lot of existing infrastructure.

Despite these very exciting data points you can watch California systematically push against these trends:

https://www.canarymedia.com/articles/solar/new-california-ru...

Yeah, I also find the NEM changes pretty hard to understand: if the goal is to shift as many people to solar as possible, why cut the incentives right when they’re starting to produce meaningful results.

> why cut the incentives right when they’re starting to produce meaningful results

Because it's unsustainable and every rooftop solar installation that has net metering causes electricity to be more expensive for everyone. The same time your rooftop system is producing its peak capacity is likely to be the same time the nearby grid-scale solar plants are producing at peak capacity, but the utility is forced to pay you retail price for the power you're producing when they'd rather get it at wholesale price from the larger facilities.

A few comments:

Your comment assumes that the utility needs to be using up lots of land to power customers. Rooftop solar is far more efficient and there is no extra transmission required. Utilities don't need to consume vast tracts of land just to provide power to customers.

> retail price

Utilities in California (by law) already deduct fees out of this, so it's not reimbursed at full retail rate anyway under old NEM rules. There's also an absolutely massive gap between retail and wholesale rates that could be explored.

If what you're proposing about rooftop solar being more efficient was true, why wouldn't the utilities just pay to roll that out to residential customers? E.g. the utility pays to install the panels on your roof and then you get a discount on your electricity to pay for the "roof lease"?

It is because utilities can externalize many costs with their current development practices. Every now and then the federal government jumps in with some more funding for them too (see: Diablo Canyon). Incentives aren't aligned between the utilities and their customers.

> It is because utilities can externalize many costs with their current development practices

I'm curious what you mean with that statement. Which costs are they able to externalize by building grid scale solar that they'd have to cover out-of-pocket for a grid-scale rooftop solar deployment?

> Incentives aren't aligned between the utilities and their customers.

I mean, as a first approximation the utilities incentives are:

- keep capex and opex costs as low as possible

- while selling electricity at the prevailing rate inside their RTO

"Shorting The Grid" by Meredith Angwin paints an absolutely atrocious picture of the governance structures inside many RTOs and there are definitely perverse incentives at play, but fundamentally the utilities want to sell electricity while maximizing their margins.

I'm not even sure what the "customer incentives" are beyond paying as little as possible to keep their lights on and houses heated and cooled.

> Which costs are they able to externalize by building grid scale solar

The biggest one is transmission. Most utilities have an arrangement where they can receive a certain return from customers with new capex. No large-scale transmission is required for rooftop installations.

Thanks for the book recommendation. I'll have to check it out.

> "customer incentives"

Correct. Customers are incentivized to use as little as possible and therefore save money. The utilities are incentivized to get customers to pay for new projects to earn a guaranteed return. And if a customer overgenerates their credits in a net metering scenario? Typically this is free energy to the utility. No payout.

I think the idea is that California has plenty of solar generation during the day (or is on track to have plenty); what it needs is storage for when the sun isn’t shining.

The new NEM (the Net Billing Tariff) shifts the incentives away from solar generation (which the utilities have a lot of) and towards energy storage. I am in the market for solar right now, and I’ve been running the numbers. Whereas I would have had the greatest ROI with a large solar panel array under the last NEM, I now get the largest ROI with a small solar array + a battery.

I can’t say that my ROI will be the same under NEM 3.0 as it was in the old NEM, but solar is not suddenly a bad investment, as some might claim. A small solar + battery setup will pay for itself in 5 years in my situation. A battery alone (no solar panels) pays for itself within a decade, since you can buy energy for “cheap” during super off peak and store it for use during peak hours, pinning your electricity costs to the lowest of the day.

This is all with existing rates. The upcoming shift to an Income Graduated Fixed Fee will likely come with reduced per-kilowatt-hour rates, which will reduce the ROI for home solar and batteries.

These trends are precisely why NEM has to change.

I hope we can also make the cultural shift towards the goal being clean, plentiful supply as opposed to constrained demand.

Load shifting would certainly help achieve the goal

Couldn't agree more. We have so much untapped clean power radiating down onto our planet in the form of solar energy. Enough to provide every single human being with an energy budget far far in excess of a typical American.

Yet so many people only fixate on the "solution" of "you must use less and have a shittier, less-comfortable life, there is no other way!".

We are a civilization that fundamentally requires energy for all our wants and needs. People need to get over that and focus on gathering energy cleanly.

If energy is like money, then this is the old 'increase your income or decrease your expenses' dilemma. Increasing income is naturally the more desirable option, decreasing expenses can still be a reasonable temporary measure until you can get that promotion/career change/side hustle off the ground.

If energy is like money, demand will always increase to be just slightly over supply.

Or decrease to be just slightly over supply. We don’t like to think about it but the current energy mix plus geopolitical factors make that a distinct possibility.

Yes, of course. But parts of the discourse make it sound like we need to reduce our energy usage as some kind of 'moral imperative'. They give the impression that they'd be disappointed if everyone could get everything they wanted with zero cost to the environment.

The abundance agenda!

We will need to overprovision solar and wind for winter so yes electricity will likely be abundantly available most of the year.

It seems like the neighborhood is the sweet spot for battery deployments - Easier to spread capital allocation, Lower stress on transmission lines.

Are any organizations working on neighborhood storage in a big way?

There was one retirement community in Florida that was talking about this:

https://babcockranch.com/our-vision/core-initiatives/

"In partnership with Florida Power & Light, Babcock Ranch houses the FPL Babcock Ranch Solar Energy Center and FPL Babcock Preserve Solar Energy Center on 870 acres of land. Each one is capable of generating 75 MW of clean energy, for a combined total of 150 MW capacity and 680,000 solar panels. The FPL Babcock Ranch Solar Energy Center ensures that the net production of clean, renewable energy at Babcock Ranch exceeds the total amount the town consumes.

Another exciting part Babcock Ranch’s clean energy program? We house the largest solar-plus-storage system operating in the U.S. today. Created by FPL, these ten large gray steel battery storage units can store 1 megawatt of power and discharge for 4 hours. The new battery storage system ensures a steady supply of power on partly cloudy days and at night."

Small Florida community aims for energy independence by harnessing the power of the sun

https://www.youtube.com/watch?v=s7TrBu_uEhI

> In Spain, electricity provided by solar increased 8 percentage points Y/Y, from 16% to 24%.

This increase is only for the month of July, not Y/Y.

“in Fall 2023” my goodness this post is from the future!!!

I've always found it weird that people take the calendar at its word for when the seasons start and end. Does December 19th ever really feel like winter hasn't started yet?

I prefer the meteorological seasons:

https://www.accuweather.com/en/weather-news/why-meteorologic...

Calm down.

The world consists of two hemispheres with opposite seasons.

Let's cancel out that possibility first.

Or the southern hemisphere

Lots of people on HN only talking about solar recently. Solar will not solve all our energy needs.

- Batteries are not cheap, nor renewable. Just because there may be advances in the future does not mean batteries are going to always be cheap and freely available. They are also currently quite dangerous to deal with.

- A society based on only solar would have to reduce its power needs in winter, or increase its solar generation capacity to account for winter losses. (Winter losses is largely the shorter daylight hours, but also snow in northern climates)

- Solar only works under ideal conditions, which is to say, in daylight, without clouds, smoke, ash, snow, etc. Even if you have batteries to account for occasional environmental losses, those batteries probably won't last for weeks on end in the event of the more bizarre weather that climate change is bringing.

- At some point, people run out of land to put panels on. Geography and legal/political boundaries around the world vary. Sometimes there just won't be enough land.

- A lot of the cheap manufacturing is centered in one or two countries, which creates a political and economic disadvantage to the rest, if they become over-dependent on this energy generation method. Look at what's happened recently from a loss of access to cheap natural gas.

- Transmission/distribution/management is still a significant challenge which is not solved; you can have all the solar generation you'll ever need and still have power shortages.

Who is advocating a solar-only future? Whom are you arguing with?

No one is proposing a solar-only future, and this guy's comment isn't arguing against that...

His comment points out valid concerns for a future that appears to be trending in the direction of relying more and more on solar power - these are real concerns even if solar accounts for ~20% of all power generation, not some 100% solar-only future. It's a reminder that solar power is not some silver bullet solution to energy generation.

GP said "A society based on only solar would"

I've been hearing these "concerns" for 25 years, yet as the link shows this has not stopped a an ongoing explosion in solar investment - presumably a large chunk of that from people who are not complete fucking idiots and are aware of OPs 1990's-era concerns.

Behind the objection to the solar-only future are fears that this turns the high latitude white countries into energy ghettos. Solar, the anti-colonial energy source.

Solar's experience rate is greater than any other energy source. In the long term, can even wind keep up?

There is a simple solution to all these problems. Continue to use fossil fuels as we currently are and build massive solar plants attached to carbon sequestration to hit net zero emissions. And that's only the most obvious one, no one is suggesting we generate 100% of electricity from solar.

My favorite take on this sort of issue: "Can we just get the 90% done first?" [1]

The faster we build solar, the better. We can sort out lots of things along the way.

[1] https://twitter.com/JigarShahDC/status/1701228390735602048?t...

Go ahead and build out all the solar possible. Then not have any way to distribute it, balance the load, recoup the cost from customers, supplant new energy demand outside of a narrow band of peak sunlight hours. Then not be able to pay back all the loans you took on building it out. Then cause the state to pay for the defaulted loans. Then have the unmaintained infrastructure break down and become a writeoff. Then have the economy slowly go downhill due to wasted govt investments, lack of jobs, lack of new investment, and literally lack of power (a shuttered coal plant isn't a flip of a switch to turn back on).

It is not enough to merely fill bids for new generation contracts. There's this assumption that just because you build it, everything else will come. This is a dangerously shortsighted view of the world that only people hoping to win a quick buck on a stock price increase will sell you on. Anybody pushing this idea is vested in a green energy company.

A nation isn't a start-up. There are real-world consequences to running before you can walk. People need to come to grips with this or we're all gonna suffer the consequences.

Holy slippery slope Batman! Was there a suggestion here or just the fear of uncertainty?

The world is filled with uncertain and dangerously shortsighted ideas. Our current power grid has been unintentionally (arguable) geo-engineering the planet for more than a century. Whoopsie daisy.

You're right, the world isn't a startup; there's more to life than financial incentives. I have a lot more tolerance for risk when it comes to the profits of green energy corporations than I do with our collective future.

> - Batteries are not cheap, nor renewable.

Forget batteries for now. How about replacing half of the US that is using coal in the middle of the day?

> - A society based on only solar

Said no one

> - Solar only works under ideal conditions, which is to say, in daylight, without clouds, smoke, ash, snow, etc.

Ok, use them for those ideal conditions then, not coal or nat. gas.

> - At some point, people run out of land to put panels on. Geography and legal/political boundaries around the world vary. Sometimes there just won't be enough land.

You must be joking. Take a look at all the land in the US. Especially in places that are >50% coal in the day, like Wyoming, Montana, and most of the Midwest.

> Batteries are not cheap, nor renewable

Batteries are MUCH cheaper and their prices are declining. Especially at grid scale. There are MANY ways to store energy surplus, we're not at that stage yet but we will get there.

Batteries can be recycled. Again, especially at grid scale. Since they contain renewable energy for later use I'll call them WAY more renewable than gas/oil/coal.

> A society based on only solar

No one said that.

> Solar only works under ideal conditions

This is untrue. There are two types of solar, photovoltaic which is what most of us talk about works even under cloud coverage. No, it won't get 100% efficiency but it will give you energy during the day.

Couple that with the fact that wind is stronger during those seasons and that there are other sources of renewables and you will get a more even picture across seasons.

> At some point, people run out of land to put panels on

Right now most deployments are conventional and we still have plenty of land. Unlike regular energy factories we can place panels above every single interstate. Many crop fields and keep the crops which actually grow better and improve electric generation... Every building, every parking lot and right in the middle of the city.

Unlike other means of electric generation this can be deployed everywhere. The main things stopping us from doing it are time, costs and incentives.

Governments regulate roads and can provide financial incentives, they stopped so the costs aren't as great. But with the continued drop in price of panels I'm sure we'll see a lot more of that.

> A lot of the cheap manufacturing is centered in one or two countries

This is just weird. I have no idea what you're claiming here. That if China decides to stop selling or raise the price of panels it will be a problem? Do you know who controls Uranium? Oil?

Nice thing is that these are "renewable. Once installed we don't need to worry about China for 25+ years...

> Transmission/distribution/management

This is the one correct point here... But not really.

Right now coal/gas plants need to be far from the city center so transmission is expensive. You don't want to breath that in. So should nuclear, you REALLY don't want that near your building.

You can have a solar roof right above your head. The road leading into your city can be solar. Batteries can be stored right outside the city and save the cost of transmitting... They can be underground which further saves on real-estate. A smart grid can take advantage of all of that.

The problem is that the grid is also very out of date and not interconnected enough to trade surplus. This is something that governments need to fix. Even between countries e.g. northern states should sell surplus to Canada and vice versa.

I'm for the free market here. The free market needs an infrastructure to work on. Since solar and wind are some of the cheapest options around, once the grid is properly open and modern, the market will take care of everything. Obviously, that's a huge investment but it will make energy cheaper and cleaner for everyone.

This is the same old dumb hand-wringing, if we replace all daytime sunny-location generation with solar and use fossil fuels for everything else, it's still massive progress.

Tesla's plan for Earth's energy needs seems workable https://www.tesla.com/ns_videos/Tesla-Master-Plan-Part-3.pdf

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