Did you mean "Yes, I have a system" or "Yes, you can sell energy". Not clear.
If you do have solar:
What size is your system?
Are you in the US?
If you do have solar:
What size is your system?
Are you in the US?
https://i.imgur.com/FLvXi0w.png
40 x 325 W panels feeding two SMA 6000W inverters. That's enough because you'll never make peak label power. The most I've seen is 11 kW peak. Lots of reasons for this. One of them being the permit authorities limiting the tilt angle of the array to 15° due to zoning/planning/whatever code. No big deal. I am adding a third inverter and more panels this year.
Not sure how things are done in New York. Here in SoCal it isn't as simple as selling excess energy back. The accounting is like going to the casino, it's heavily tilted in favor of the house. They are paying a useless amount of money per excess kWh. With NEM-3 coming-up, the incentive to install solar are mostly gone (which is a serious problem).
I have been looking at shifting into the tiered power metering plan. I can't do it until I take the time to fully model it and understand what will happen. A quick top-level analysis says it should actually be better than NEM TOU plans because you never go into high tiers at all, particularly with a decent system.
To make things worse, the true-up calculation is just killing people these days. We have great relationships with a dozen of our immediate neighbors. We talk about stuff like this all the time. I can't think of one who is currently happy with solar. Please understand that none of them bought their system. They were sold a small leased system that was barely adequate. So, they end-up with something like a $150 to $200 per month lease payment, another $150 to $300 per month in energy bills (because they can't make enough with solar) and, on top of that, they get hit with hundreds of dollars every 12 month when the true-up calculation is done. It's crazy and NEM-3 isn't going to help at all.
Going back to what you were saying...
> There is no need for "ten times" overbuild. Instead, you just need a backup generator you can fuel at need.
I hope you are not proposing that every solar owner should have a backup generator. For one, those things are horrible polluters.
Please note that the 10x overbuild is based on simple mathematical realities. One of the examples I gave was the need to double the system to store energy for night use and a multiplier of 1.5 (a total of 3.0) as a result of energy being the integral of the ideal-case parabolic generation profile. In other words, these numbers are not a matter of my opinion, this is physics. If you want constant power 24/7 you have to start there. Once you calculate all other factors the number very easily goes above 10x.
Another example, here's a basic derating calculation:
https://i.imgur.com/KbS0aev.png
This math requires increasing the array size by 1.5x again. We go form 3.0 to 4.5.
Etc.
If you do the math, 10x is an understatement.
> Building storage after you have enough renewable overbuild to charge it from
I understand what you are saying. However, there's an intersection of curves where things just do not line-up. It's already happening. Utility companies are raising prices and consumers are going to get hurt (NEM-3, again). I forget the exact numbers. When I installed my system 1 kWh was about $0.15 off-peak. Today, depending on the plan, you are in the $0.28 to $0.35 range.
As more solar is installed the balance will cause serious side-effects. I don't think we fully understand what will happen.
> A low duty-cycle backup generator should be, above other considerations, cheap. Don't you have one? They are cheap.
I don't need one. My system allows me to generate power (up to 4 kW) if the grid goes down. That's why I chose the SMA inverters. When I add a third inverter this will increase to 6 kW. Yes, of course, the sun has to be up and no clouds, etc.
I will eventually add batteries. I just doesn't make any sense right now. The ROI is horrible. Also, if you do the math, the amount of energy you have to store to literally weather the storm (if you want to be 100% off-grid) is insane. Looking at what happened in December/January, we are talking something in the order of 500 kWh. And, of course, this would require an equally massive array to keep the batteries charged.
My conclusion is that going 100% off grid with 24/7/365 reliable power and no compromises is pretty close to a fantasy. Before concluding this is crazy, take a look at this calculation from a battery manufacturer:
Their conclusion is you need 56 kWh to survive just FOUR days if your home requires 10 kWh per day. My air conditioning system alone burns approximately 5 kW and, in the heat of summer, it is on some 12 to 16 hours per day. That alone blows-up the 10 kWh/day budget. Still, if we stick with that and decide we need to be 100% reliably off-grid for 30 days, not 4, the number is 420 kWh.
In other words, my estimate isn't crazy at all and the idea of homes existing 100% off-grid is a fantasy for most.
Which brings me full circle to having to have 100% reliable external power sources that can deliver 100% of the power a town or city might require at any given moment for short or long periods of time. That's the part I can't reconcile. I can play with solar. I can throw money at it. However, at scale, not sure. That's why I talk about nuclear. Pick any other technology. My conclusion is solar alone isn't going to happen. Not at scale.
Solar alone obviously can't happen, most places. Solar + wind + hydro + (sometimes) geo + (even) old nukes + storage + xmission line + backup combined-cycle gas turbines will, instead. Backup gas turbines will burn NG at first, synthetic ammonia or hydrogen later.
Getting 100% off-grid is not a goal worth the extra cost, for most. For anyone without access, or with unreliable mains, a backup generator is just prudent. Batteries, if you have any overbuild, mean you spend on mains or run your generator less often.
At utility scale, with regional-grid tie-in, calculations come out differently. Maybe the gas turbine runs part of most weeks, this decade, rather than once or twice in winter like your backup generator. Wind and transmission line complement solar.
Battery cost is radically less than 2 years ago, and still falling. If you haven't checked lately, prepare for a surprise.
Exactly my point.
Yet, beyond that, the analysis shows you have to have 100% backup rated at 100% the required peak power output.
That's the conundrum. For every deliverable GW of of solar you have have a GW of backup.
And so my question is simple: How does that make any sense at all?
Let's make sure we don't engage in a hand-wavy arguments though.
Wind: Regional, seasonal and varies throughout the day
Hydro: Not available everywhere, highly seasonal. Check out this chart [0]. Hydro is susceptible to water availability. Hoover Dam lost 33% of it's output capacity for this reason --about 600 MW.
Geothermal: Sounds great. Only 0.4% of US utility scale generation
Old Nukes: 20% of US power generation. We have over 80 of them. Only three of them in the west [1] (which is astounding)
Transmission Lines: They are only good for about 300 miles. Power is relatively local. Hoover Dam feeding Los Angeles is about 250 miles straight line.
Combined Cycle Gas turbines: About 20% of US capacity. None west of Texas.
Anyhow, the point is that it is easy to list all of this power generation options and lose sight that they are not available everywhere and adding capacity is nearly impossible. In fact, if you look at the maps showing distribution of the above power sources in the US it isn't too hard to conclude that the west coast is not in good shape at all.
Here's the kicker: I haven't even introduced the reality that 100% conversion to electric powered vehicles will require the US to double it's power generation capacity. This is monumental. Conceptually, it means we have to fully duplicate our existing generation and transmission infrastructure. Frankly, I don't know how we make that happen. Please don't say solar. Once again, nuclear keeps coming back as a source that is impossible to ignore. We need so much power to support electric vehicles that we would need to build 1200 new 1 GW class nuclear power plants. This is impossible. Clearly a hybrid system will be required. Again, no, solar can't do it. It can be a part of it, but it just can't rise up to the occasion.
[0] https://en.wikipedia.org/wiki/Hydroelectric_power_in_the_Uni...
[1] https://en.wikipedia.org/wiki/Nuclear_power_in_the_United_St...
Say what now? Are you trapped in the 1950s or something?
> Most HVDC links use voltages between 100 kV and 800 kV. However, a 1,100 kV link in China was completed in 2019 over a distance of 3,300 km (2,100 mi) with a power capacity of 12 GW [1].
I realise the USofA is stuck with a lot of old infrastructure that they've only recently barely started to upgrade .. but better things are possible.
[1] https://en.wikipedia.org/wiki/High-voltage_direct_current
No. Reality.
Where in the US do we have a power transmission line that goes significantly farther than 300 miles?
Also, if I had to guess, I would not be surprised if the super high voltages required to go farther are so dangerous to people, wildlife and the environment that they will never be build in the US or Europe. China doesn’t care about such things.
Here's a map of HVDC projects in Europe, some of which have been about since the 1930s [1].
Canada has several long distance HVDC lines (eg: [2] "recorded on the list of IEEE Milestones in electrical engineering") while the US to date mainly uses HVDC to interconnect existing AC grids (eg: [3]) although there are significant proposals for long distance HVDC to share renewable energy.
[1] https://en.wikipedia.org/wiki/List_of_HVDC_projects
[2] https://en.wikipedia.org/wiki/Nelson_River_DC_Transmission_S...
[3] https://ethw.org/Milestones:Virginia_Smith_High-Voltage_Dire...
> the super high voltages required to go farther are so dangerous to people, wildlife and the environment
This is another of your blindly inaccurate unresearched guesses?
Can you back this up with reference to the past 50 years of HVDC in Europe and demostrate DANGER!! at levels significant over AC transmission?
Where in the US do we have a power transmission line that goes significantly farther than 300 miles?
I'll point out this argument would also rule out Gen IV reactors and breeders, which we also don't have in the US. Without breeders, the world economy cannot go nuclear, so I guess you're all on board with renewables now?
Consider three cities and four generators with a 300km transmission line between each.
g1--C1--g2--C2--g3--C3--g4
Each generator normally sends 1GW into each transmission line, but today g1 produces twice as much amd g4 produces nothing. g1 powers C1, g2 powers C2 and g3 powers C3.
The electricity must have teleported 1800km, it's the only explanation. Otherwise you'd have to consider an idea like some kind of 'network' of 'transmission' and that you need to model an entire system with nuance rather than pretending each element is completely isolated and has a constant load with no variation.
Similarly energy can go through more than one interchange. Electrons don't have a little ttl counter, it just reduces efficiency some.
That is utterly silly. Think.
You need only just enough backup generation capacity to fill a shortfall. In contrast, you overbuild solar and wind so you can charge up your storage while also satisfying peak load even under reduced yield.
You will never, ever charge storage from your backup generator: that would be beyond idiotic. So you need only a very strictly limited backup capacity, no matter how much renewable generation you have overbuilt. You will overbuild, because it is by far the cheapest way to get power, and you can sell the extra.
Wind and solar are variable, but not random: you know well ahead of time what they will produce, and whether and when your storage will run low. So, you can schedule a fuel delivery or a slice of transmission line capacity. You might charge storage from the transmission line if you are not producing enough excess, which will be cheaper than ordering in liquid fuel.
Your figures on transmission lines are badly dated. UK is building a transmission line to a solar farm in Africa, which is rather more than 300km away. (Siting a solar farm in the desert is also idiotic, but people who control money love the idea, so here we are.) China wants to build one to Chile, their antipodes; they figure on 50% loss, which is fine.
We will need a lot of power generation and transmission. Renewable generation is cheap and still getting cheaper fast. So it is obvious what to do: build that. Keep building that.
Diverting capital to nukes (or geo) would radically cut generation capacity. More expensive means, exactly, fewer watts per dollar. Fortunately nobody with money is dumb enough to buy a nuke, even with DoE doing their level best to sucker somebody on board.
If we are very, very lucky, civilization will not collapse before enough is built out.
Here's a concept: How about we have a conversation without insults?
Explain this to me then:
Let's say you have a 1 MW array in, say, Los Angeles. Let's assume not a cloud in the sky most of the year. Not true. Let's go there anyway.
We then get pounded with rains and have black clouds and dark skies for a couple of months (pretty much the kind of thing that happened in December/January).
Power output goes down from one million Watts peak to 75000 Watts peak for days and days.
How much backup --in any form, any technology-- would you propose to have in order to ensure the town, homes, people, hospitals, traffic lights, etc. relying on this 1 MW of power does not go dark during those two months.
Pick any technology. I don't care what it is. What I want from you is: We need x Watts of power as backup to survive this period. Power, not energy. There's a huge difference.
Since you think my statement is silly, I am assuming you think you can supply this town with a lot less than the 1 MW they lost during this blackout. How?
Nobody is relying on 1000 kW from that array. If it is a 3x overbuild, then they are counting on only 300 kW from it, with any extra going to charge storage or put on a transmission line to sell. Their shortfall under stormclouds is then 300-75=225 kW. After their storage has been depleted, if power from elsewhere is already spoken for, that is how much they will draw from their backup generator. At night, when the array produces zero, demand is lower, but anyway their backup generator can take the whole 300 kW load when necessary.
But it is not often necessary. Often they can fill the shortfall from storage or from a transmission line with power from elsewhere, maybe wind, or maybe even from the next town's storage if they predict they won't need it right away. The town will deliver excess stored energy they have on the same terms.
After developing some experience, and prices for panels have plummeted further, maybe the town builds out another 2x. Then they generate 125 kW under storm conditions, and the shortfall is only 175 kW. The rest of the time they can charge their storage faster and then sell more to the grid.
How much to spend overbuilding generation vs. how much on growing storage capacity is a complicated calculation. Both are capex for equipment that cuts hard-to-predict costs. Building more later gets you lower prices, but only starts saving you money after it's built.
Of course in practice all the solar and wind farms push to the grid at the bid price, and the town draws power from the grid at the asking price. Storage and gas generators push power to the grid when bid price exceeds their profit threshold. Storage draws from the grid to charge when the asking price is low enough, which is never when the gas generator is pushing. Nukes never see the bid price exceed their cost, but must take what is offered or shut down; all not heavily subsidized via tax will shut down.
Anything you write that is not silly, I promise not to call silly.
If you NEED 1 MW, you also NEED 1 MW for backup from a different source. It can be solar or wind 300 miles away, where, perhaps, the weather is different. Yet, you still need 100% backup.
You are all so focused on having a verbally violent argument that you cannot help but deflect with tangential issues and fail any attempt to try to understand and be understood.
There, I just gave you the perfect refutation to my suggestion of using nuclear for backup. Use solar or wind from a few hundred miles away. Perfectly doable? In principle, yes. It requires analysis but it does sound plausible.
I'll give you another refutation to challenge a claim that nuclear power is the solution: While the technology has gotten better and we can build better reactors, hell will freeze over before we build a few more reactors in the US, much less hundreds. A case of "Yeah, that's great. You just can't build them. Ever".
There, that's how you try to have a conversation with someone if you care to actually have one from a basis of respect and the potential of mutual edification. I am so sick of people who use online conversations as free-for-all confrontational battlegrounds. Nobody learns anything other than who might be the biggest jerk or who subscribes to the same mob.
This "conversation" is over.
Your 1st percentile weather event brings your peak power down to 1.5MW and the average over the week down to 500kW.
Your 500kW shortfall is filled with whatever combination of storage and dispatch you have, and is rare enough that planning to fill it with fossil fuel gas for the next century is a lower cost and lower total emissions strategy than spending an extra 15 years waiting for Uranium mines to open even if you pretend all the other dispatch options are impossible.
Perhaps I have not made it clear enough that I am dealing in reality rather than things that do not exist? This cable and project are not real yet. They have yet to build the very factory that will manufacture this cable.
Also, I am talking about land-based power. The US infrastructure. Europe is screwed in so many forms that they have to resort to such things.
This cable is horrifically dangerous in so many ways. Talk about boiling the ocean! 10 GW will do that. I wonder how that accident will compare to an oil spill?
From a strategic perspective, bringing in 8% of your nation's power needs from a place like Morocco via an underwater cable does not sound like a great geopolitical strategy. Unless we want to imagine something like a large or regional war can never happen...
Then again, the UK might have few choices. I don't think they can do solar at this scale in-country. I would think they can do a massive amount of offshore wind. This is puzzling to me. I don't understand a strategy that creates such a dependency. Look at what happened to Germany and others with Russia. I don't get it.
An underwater cable pushing that kind of voltage and power for such a long distance is likely an ecological disaster waiting to happen. I'm sure they have safeguards...just like offshore oil rigs.
UK's folly in relying on Morocco for power is way off topic. UK certainly is not limited to relying on power from Morocco. They could put up solar fencing in their abundant pasture, sharing with livestock that will keep down weeds. But UK is not known for excellent governance, lately.
10GW, ignoring the ability to shed energy over time, would take ~16 million years to boil the ocean.
Yet another demonstration of a complete inability to perform basic arithmetic or critical reasoning. If for some reason it were to break and put all the energy into the ocean, and then for some reason the operators decided to put $100k of energy into the ocean each hour rather than turning it off. Then it would be about 20% more than browns ferry dumps into wheeler lake under normal operation.
This is an unfathomably stupid take.
If every truck including all the small ones were a tesla semi, and every car, pickup or motorbike were a ford lightning, then this is an average load of around 200-300GW. 150-200GW is more realistic. Simply plugging in most cars most of the time and using grid aware charging would solve this, but if that's really unfathomable you can just duplicate whatever portion of the battery is used each day (<10% on average, less on some cars, more on others) and leave some of it at the charger and some at the solar array or wind turbine.
Daily gasoline demand is fairly consistent and quite elastic, it drops about 20% in winter and has minor spikes on holidays. Price signals can and regularly do control for this, but overbuilding 20% or simply taking advantage of many of the air conditioners or heaters being off is more than sufficient.
This will lower transmission strain rather than raise it, as it allows all the energy to be transferred during off peak and allows peak smoothing.
Long haul trucking will likely opt to schedule charging in blocks rather than have two redundant batteries for each truck. This is fairly easy to do as they know where they are going. Running chargers at 3MW per bay without storage wouldn't work anyway and no large multi bay truck chargers are planned without colocated storage or generation.
You're right that 1.2TW of nameplate generation would solve this easily but it is 1.2TW of solar built at <30c/W over the next 10 years, not 1.2TW of nuclear built for an average cost of $20/W (including all the failures that still need to be paid for) and rising. 500GW solar and 300GW wind would probably also be plenty.
Add the same constraints to a nuclear system and it a) does not exist and b) still needs a month of storage for outages.
So these neighbors are paying the full cost of their 3kw to 5kw systems every 2 to 3 years? Sounds like they're right to be pissed if they didn't knowingly opt in to being early adopters in 2008, but the problem isn't the solar panels.
Even with that, they're still only paying a little above retail for their electricity. If the bill is causing hardship then maybe the solution is to stop using an order of magnitude more electricity than is necessary on luxuries?
People taken in by hucksters of any stripe suffer. There is nothing unique to or characteristic of solar in that. People who have shopped carefully are doing extremely well with solar, especially for recent installs.
And again, having your society be full of scammers has nothing to do with the viability of solar. Nor is signing a lease whereby you pay full retail cost for the electricity generated actually a step down from not having the system installed.