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Comment by macspoofing | Hacker News Reader

>"hey fossil fuels, let's 1v1" sincerely, solar

Let's do it. Let's see how well solar does at night, or on a cloudy day, or during winters, or evenings, or early in the mornings.

The problem with solar (and wind) is not really the price. The problem is that it is intermittent power source that cannot, by itself, power a modern economy and there is no battery technology to bridge the intermittency gap. That's why it needs to be paired with natural gas (or bio-fuels, or another carbon-based energy source) to make it remotely viable. This is why natural gas companies are one of the biggest lobby groups for wind and solar.

Worse, wind and solar are atrocious for nuclear, because nuclear cannot wind-up and wind-down the way a natural gas generator can.

View on HN

This is one of the most blatantly pro-fossil, anti-renewable posts I have seen on HN.

First off, yes there is battery technology to bridge the gap. Solar+battery storage is an increasingly common purchase for utilities today, there are home-batteries for purchase for consumers from multiple companies. To say battery storage doesn't exist and isn't cheaper than oil/coal grid power is simply false.

Second, renewables can have higher capacity factors than many fossil-fuel plants, so saying they're intermittent and fossil-fuel is not is false. Surely, solar is weaker in winter, but wind is stronger at night, and seasonal storage is the main issue here. Yes, we will be using natural gas for winter and certain Northerly regions for decades to come, but it will become increasingly niche/reserve as batteries, solar, and wind get even cheaper.

Renewables absolutely do not need to be paired with natural gas to make it "remotely viable". There are numerous markets with very high % of renewables already, and it turns out utility operators are very smart and know how to plan very well. Renewables can reach very high market penetration, given solar is a day resource and wind is a night resource, in general. The main issue is bringing demand response online to tailor your loads to fit your renewables: charge EVs, batteries, use AC/heating, industrial processes, all can be tailored to the price of electricity, given a smart utility.

>This is one of the most blatantly pro-fossil, anti-renewable posts I have seen on HN.

Reality itself is pro-fossil. Fossil fuel is very damaging, but it's also an excellent, almost free, source of huge amounts of stored energy left for us to discover and use...

Solar/wind are much cleaner, but oversold.

If we got rid of fossils tonight, we'd be in the dark ages for decades (if not permanently). Even building solar/wind installations, at the moment, relies on fossil fuel infrastructure, plus the traditional grid required...

>First off, yes there is battery technology to bridge the gap.

Not at the scale requited to bridge the gap. "home-batteries for purchase for consumers" do their job because the demand and use is still very small...

>(...) so saying they're intermittent and fossil-fuel is not is false (...) Yes, we will be using natural gas for winter and certain Northerly regions for decades to come

Well, they are intermittent, and fossil fuel is not.

>Renewables absolutely do not need to be paired with natural gas to make it "remotely viable".

You just wrote: "we will be using natural gas for winter and certain Northerly regions for decades to come"...

Countries don't spend trillions on fossil fuels because "solar/wind is cheaper" and storage is "a solved problem", or because of some big conspiracy - they do it because it's not...

No, it just expose the realities of that market, seasonal storage is not a solved problem. Why would it be pro fossil ?

Battery do not solve seasonal storage, for the USA it needs 8 to 16 weeks of it, and Tesla global battery output is just a few minutes of it per years.

Higher capacity factor still doesn't mean on demand.

Markets with very high % of renewables all benefits form big hydro or geothermal sources, it doesn't apply in every countries.

Technically, storage is a solved problem. It's not even hard, and y'all keep saying it's impossible. The unsolved problem is cost. And it's a simple formula... how much grid storage is needed to account for variations? And what does that storage cost? The moment the combined wind/solar + storage cost drops below the cost of coal/nuclear, it wins.

And intermittency for wind is completely overblown (no pun intended). Tower-height winds are much steadier than surface-height winds, due to lack of surface-related turbulence. And we have a couple of decades of measurement of large wind installations, so the expected variation isn't exactly a surprise unknown.

"No, it just expose the realities of that market, seasonal storage is not a solved problem."

It's called a flywheel, batteries, pumps to power hydro reservoirs, and more. The solutions are there, you refuse to see them.

I have suggested multiple times on HN that we should set a date where all burning of fossil fuel for power and heat is banned.

The answer I kept seeing from pro-renewable/anti-nuclear people is that banning fossil fuels is unrealistic and impossible. Battery is a tiny part of a tiny part when solar/wind is not producing, as can be seen in sites that provide real time data from EU.

Take a random country in EU. Look at how much energy is produced by wind at peak. Compare it to the lowest lowest point, remove nuclear and hydro, and you get how much fossil fuels that country use at peak. For most countries that is natural gas or coal and it matches wind production almost (only almost as natural gas is a bit more expensive than peak wind, as peak wind can even get negative in purchasing price).

There is also numbers on what power plants countries are currently building. The top one: natural gas power plants. Second one, wind. The power plants we build today is what will produce power tomorrow, and the vector of where investment and constructions is being put is in favor of more natural gas, not less. Nuclear is in many places being replaced by natural gas.

But to get back on track, lets have this ban of fossil fuels in energy and heating. I wish it would happen. It would be great for the environment, force an answer with money on the table on question if nuclear is cheaper than battery, and finally distance the renewable movement away from natural gas. The Northerly regions are not really a big coal/gas users anyway because they also tend to have mountains, rivers, and few people. Hydro will work perfectly fine as long the energy does need to go to southern regions.

To put it simply: countries need to stop building natural gas powers plants and put those investments into battery or nuclear. That is the progress bar for a completely renewable energy grid. As far as I can read it stand right now at almost 0%.

Thank you for being the voice of reason <3 Small correction though on your last paragraph: nuclear is not a renewable energy, but it does not emit carbon.

Geothermal is not renewable either, but we say it is. There is so much Uranium, I would consider it "close enough"

If geothermal isn't renewable, then neither is solar. Or wind. Or hydro. Those all trace to irreversable conversion of hydrogen to helium. Geothermal comes from fission, just like nuclear.

Geothermal does not come from fission. It comes from some combination of primordial heat (which is gravitational), and alpha and beta decay (not fission).

I had gathered that primordial heat would have petered out billions of years ago. That the radioactive decay cited as providing long-term heat is not primarily fission is a surprise. But isn't alpha decay really a kind of fission? It's not useful for chain reactions, but that's a whole other topic.

No, alpha decay is a distinct nuclear process.

And the article is blatantly pro-renewable, what’s your point? If anything, the parent comment brings up issues that are often ignored and glossed over.

>To say battery storage doesn't exist and isn't cheaper than oil/coal grid power is simply false.

If that were true, nobody would be using either fossil source.

Of course it’s not cheaper. Battery technology costs so much it’s the whole reason we have the base load discussion all of the time.

Transitions take time. We can't just flip a switch from one technology to another. What we are seeing is that the cost drop over the past decade for wind/solar/gas is so drastic that coal and nuclear are simply shutting down, because it's cheaper to shutter the plant than to keep it running. Electric utilities are taking multi-billion dollar writeoffs, because that tech is obsolete.

Nobody is building coal plants now, period. Most of the nuclear projects on the drawing board are getting canceled before ground is broken, because they can't hit the necessary price targets.

The main problem with nuclear in the west is mismanagement and loss of skills amongst construction and engineering staff. Many countries haven't built a nuclear powerplant in decades, and are having difficult now.

China is doing much better, and so is France and even Russia is doing ok, as they have a larger and more experienced workforce regularly building reactors.

I live in the UK and for the past decade every major construction project I can remember was massively delayed and over budget. Currently its HS2 and crossrail. So the faults don't appear to be specific to nuclear in industry.

Nuclear failed to hits its price points in the US even back in the first building boom. There was never a time here when nuclear was economical.

> If that were true, nobody would be using either fossil source.

Sunk costs are a thing.

I want to someone to lay out for me what a solar/wind grid would look like. I WANT to be convinced. How is the intermittency gap actually bridged. Tell me. I WANT to know.

>There are numerous markets with very high % of renewables already

And what do those markets do when the sun ain't shining and wind ain't blowing?

>all can be tailored to the price of electricity, given a smart utility.

And this 'smart utility' it exists in the real world? Where?

You build a shitton of wind and solar and a good grid that is as large as possible so that it's always windy somewhere in your grid. Peak production capacity should be a good bit higher than peak consumption. During the buildout phase you replace coal with gas peaker plants (you'll need them later). Then you add enough batteries and hydro storage to get you through a night or a bad day. If you can, use demand shaping technologies, e.g. charge electric cars and run aluminium smelters when it's particularly sunny or windy. Then you add power-to-gas facilities that produce Methane from electricity and use the existing infrastructure for strategic NG reserves to store it. For long periods of low production (e.g. winter) you turn the gas back into electricity.

How much wind and solar you need depends on how good you are with lowering demand, for example by insulating homes, shifting transportation to trains and building heat pumps.

> Then you add power-to-gas facilities that produce Methane from electricity and use the existing infrastructure for strategic NG reserves to store it. For long periods of low production (e.g. winter) you turn the gas back into electricity.

The efficiency of this process is like 35%. (power to gas to power with methane).

If you're making a bunch of methane anyways, it might be OK to fill in a little with this, but this does not sound like a great overall strategy.

Why not just throw in a little nuclear for base load, and then everything looks a lot better/easier?

If solar costs less than a third what nuclear does (which is where we're headed, we're already down to half), why do you need nuclear base load? Why not just do this gas conversion?

Nuclear is basically dead right now because of cost. The biggest factor in nuclear cost is financing and interest rates, which are very risk-sensitive. When existing nuclear plants are shutting down right now, because they're losing major customers to cheaper wind power, what happens to the risk on 50 year investment scales? Risk goes up, interest goes up, and plant cost skyrockets. So the very fact that nuclear costs more than renewables makes nuclear even more expensive than before.

> If solar costs less than a third what nuclear does (which is where we're headed, we're already down to half),

Because power to gas to power delivers a fraction of the input power, and has a bunch of cost itself-- it isn't free.

I'm not saying it's free. Sheesh. I'm saying that there's some point on the price curve where it becomes cheaper than nuclear, even for base load. Now, that point may never happen. Or maybe it's already happened, and will be scaled out over the next couple of decades.

The cost of PV solar has dropped over 80% in the past decade, and we don't know what the bottom is yet.

I am saying that even if pv gets cheap enough that the input power through 1/3rd efficiency is the same as nuclear... power to gas costs a lot IN ADDITION to the input power. And then burning that gas in a power plant costs something, too.

So reaching parity seems difficult.

The cost of electrolyzers has also fallen dramatically.

On the other side, gas turbines are incredibly cheap. A simple cycle gas turbine plant costs as little as $400/kW, vs. $10,000/kW for a nuclear plant.

It's this huge cost advantage of combustion turbines that is making natural gas such a killer competitor these days (along with fracking).

Sure, but the point I am making is: having the input power alone cost the same as something else is not the same as reaching cost parity with it. Because one must consider all expenses, not just the expense of the input power.

Solar has not reached cost parity with nuclear. It has blown through cost parity. Solar and wind are 3-4x cheaper than nuclear, on a levelized basis (depending on location). This gives them both plenty of space to implement storage, curtailment, transmission, and/or demand management and still beat nuclear.

Person A says if solar is 1/3rd the cost of nuclear, and energy-to-gas-to-energy is 1/3rd efficient, it should be cost-neutral with nuclear.

> If solar costs less than a third what nuclear does (which is where we're headed, we're already down to half), why do you need nuclear base load? Why not just do this gas conversion?

I objected, because energy to gas costs money, and gas to energy uses money. You have to count the other costs before you can assume cost parity.

Simple enough?

It is cost neutral with nuclear during those occasional times when you're burning the gas to make power.

It blows the socks off nuclear at other times.

But nuclear needs to get its high prices 24/7 to make economic sense. Otherwise, the cost of that 20% capacity factor nuclear is going to balloon even higher.

Simple enough?

We are talking in two different subthreads at the same time.

Stick to the argument here. It is very simple.

Power->gas->power requires capital costs and operating costs. Even if PV is 3x as cost-efficient as nuclear, PV power divided by three and then paying for p->g->p is not cost neutral.

P->g->p has to pay for its costs over the narrow times where it is actually filling in. The rest of the time it is a dead weight.

Ah, but the capital cost of p->g->p is very low, per kW of capacity, compared to a nuclear plant. Like, an order of magnitude cheaper. Combustion turbines are so damned cheap compared to nuclear plants.

(The p->g part can be spread out over longer time periods, with the gas stored underground.)

Capital cost is around $3000/kilowatt of output for p->g.

This is hardly negligible-- indeed it's nearly half the capital cost of nuclear, and doesn't include the costs of storage, the cheap combustion turbine, or the infrastructure to produce the extra input power. Duty cycle for this infrastructure is going to suck, too, because presumably we're not going to be overproducing all the time.

Also, burning the fuel may not be so cheap. Best way to improve the capital cost of p->g relative to actual work done is to do combined heat and power... but this adds its own complexities and costs.

It may prove to be an important piece of the mix, but again: diversity is good.

I want you to be explicit in that $3000/kW figure. Is that per kW of peak OUTPUT, or per KW of effective INPUT? The input cost is spread over a longer time, so the capital cost there per kW is less important. Using nuclear for this would put all the capital cost on the output side, where it is more expensive, operating at a low capacity factor.

Consider a system intended to cover occasional shortages, happing 10% of the time. The p->g->p system would have to generate hydrogen at ~1/10th the rate it is consumed. So, if the turbines are 40% efficient, 1 kW of output capacity would require .25 kW of hydrogen generation capacity (measured in the energy content of the hydrogen; multiply by another smallish factor for efficiency of the electrolyzers).

In contrast, 1 kW of coverage from nuclear would require 1 kW of expensive nuclear capacity. You might be able to claw back some of that cost by selling power at other times, but you'll be getting only a small fraction of the total cost of making it at those times. So, the fixed costs of that nuclear capacity are going to have to be earned during that 10%, and the rate that would have to be charged would be ruinous.

I don't see how nuclear could possibly be competitive for this, if one analyzes the situation properly.

> Consider a system intended to cover occasional shortages, happing 10% of the time.

Which means, in turn, that renewable has to be engineered to be sufficient for 90th percentile circumstances.

And that GTP has to have turbines sufficient for 99.99th percentile - 90th percentile circumstances. This may be a rather long tail-- in the 99.99th percentile circumstance, renewables may be making very little and demand high.

And that PTG has to have electrolyzers that have enough capacity on, say, 0-60th percentile circumstances (because you don't want to tap some things, like reservoir hydroelectric, to run PTG) to make enough gas for those outcomes.

If you have 20% of your power coming from a reliable, constant source, every step in the above chain can be much more than 20% smaller, because you absorb a lot more of the long tail and because load shedding, etc, is more effective against the remaining unreliable power.

As an aside, there's a bit of an analogy to investing. Having a bit of a low-return, reliable instrument in your portfolio is helpful. Yes, it "costs a lot" compared to investing in the market-- that 2% interest bond costs 5x as much as investing in the market to 10% average returns-- but it is a stable source of value and reduces the volatility of the cost of spending money a whole lot.

I'm in favor of doing that, but I don't think it's necessary or helps a whole lot. Nuclear power plants need to run close to max capacity all the time to make financial sense at all. So you can't use them to bridge over low production for wind and solar. They also take ages to build. Nuclear might make sense for district heating in winter, but people generally don't like having nuclear plants close to where they live.

Yah, you use nuclear for base load, and then conserve hydroelectric resources for times when you need to bridge over missing wind/solar.

It's almost like you're saying that having 30% of the power completely reliable and non-variable doesn't make the problem considerably easier.

Nuclear makes an annoyingly constant amount that has little to do with demand. Wind makes an annoyingly variable amount that has nothing to do with demand.

>Nuclear power plants need to run close to max capacity all the time to make financial sense at all.

That's right. And we know that they work and they can scale with our needs. We know we can make them cleaner and more efficient.

Maybe wind and solar just isn't the technology of the future for anything by niche applications.

Nuclear would have been a good solution if we started thirty years ago. By today we don't have enough time to go 100% nuclear before we emitted to much CO2. We have less than ten years of current emissions left if we want to stay below 1.5°. Building nuclear power plants takes longer than that.

>Nuclear would have been a good solution if we started thirty years ago.

Talk about an understatement. Imagine the trillions of tons of CO2 that would not have been emitted into the atmosphere had the developed world invested in nuclear to the same level as France. It would maybe bought us another 50 years.

Really puts into perspective the destructive force of anti-nuclear environmentalism.

>We have less than ten years of current emissions left if we want to stay below 1.5°

Hate to break it to you, solar/wind/battery isn't going to do it. It can't do it today, and there's nothing forthcoming to change that. Germany who went all in, is projecting 2060s as the time they wean themselves off of fossil fuels. France on the other hand is essential fossil-fuel free from power generation today, as is my home province on most days (thanks to Nuclear and Hydro) [1].

[1]http://live.gridwatch.ca/home-page.html

We can't get to 100% with solar/wind in a decade, either. Do what we can with solar/wind, and also start building nuclear base load.

Production of all carbon free energy, sources: solar + wind + nuclear, is not enough to get to 100%in a decade, unfortunately

"Building nuclear power plants takes longer than that."

So fix that broken process. This is a nonsense result.

And we know they will cost two arms and a leg, compared to renewables.

Yah, I don't advocate a majority-nuclear grid.

But at some point, the variability of renewables is going to start costing two arms and a leg, too. So a bit of dependable, low-carbon power in the mix sounds really good.

But that doesn't work. Adding a little bit of nuclear to a mostly renewable grid is useless. Most of the output of the nuclear plants is thrown away when the renewables are generating, so the marginal cost of covering the remaining slack periods is hideously bad. Other sources would be cheaper (in particular, burning CO2-free hydrogen in turbines, or using natural gas w. atmospheric CO2 capture.)

You add a bit of nuclear-- 10 to 30%.

Then you size wind and solar for the remaining 70-90% of load, say 70th percentile.

During the remaining 30% of the time, you use agreements that allow you to shed load and you draw upon intermittent hydroelectric resources.

The solar/wind overcapacity factor and the remaining bit of battery or power->gas->power you need can be much, much smaller because the reliable nuclear base load really stretches the hydro and load shedding.

And you can use the "extra nuclear power" when wind/solar are overproducing to pump hydro, charge batteries, or make gas for power->gas->power.

Put another way: the reliable nuclear energy just subtracts a constant amount from grid demand, and the remaining wind/solar production variability is reduced proportionally.

Your proposal doesn't work, though. It requires that nuclear be subsidized by buying its power 24/7, even when much cheaper sources are available. This opportunity cost, if properly accounted for, makes the cost for the gaps that nuclear fills in for very very expensive. Trying to use the excess nuclear for hydrogen production, battery charging, etc. doesn't save you, for basically the same reason.

Nuclear is expensive, and you can't shuffle that expense around under three walnut shells hoping it will somehow disappear.

Obviously the proposal does work, in that France basically has it implemented. and has 1/10th the emissions per unit of electricity of countries that have moved heavily towards renewables only, and some of the lowest electrical prices in Europe. ;)

You're playing with apples and oranges. You want us to look the other way while all the exotic things done to fill in for renewable supply/demand mismatches are not amortized over a tiny number of hours of operation, but want to point to the same problem with nuclear.

A diversity of power sources, each with their own problems (cost [nuclear/storage], invariability [nuclear], volatility [wind/pv], total resources available [hydro/geothermal] is what will get us through this. Especially since we're really maxing out what we can do with wind and solar and it's not going to ramp high enough in time to save us.

No, I continue to think you are mistaken, for the reasons I've given. I think if we optimize out the energy system of the future, taking into account cost of construction and operation, it's going to optimize to 0% nuclear.

France's past system is irrelevant, since it was built at a time when renewables were completely noncompetitive. The world has changed now, and changed radically. Going forward, France will be going renewable too.

France is evidence that we can readily get to low carbon electric grids using nuclear power and relatively little technology.

Sure, it's expensive, but all the things we'll have to do to have an all-renewable grid are pretty expensive themselves and unproven.

Yes, we should end up with a much smaller mix of nuclear than France had, to help optimize cost. But it is an option available now that we know will work, and I believe that the optimum point is not 0% nuclear. (In western democracies, though, nuclear has become practically impossible. This hasn't stopped a large amount of reactor construction in China, so obviously planners there disagree with your assessment).

Further, nuclear and wind are comparable in CO2 emissions, and PV is a few times worse. So if we really care about minimizing CO2 there will be some nuclear in the mix.

Betting everything on power->gas->power when we have basically no evidence that this will be economical at scale is crazy. Betting on pumped hydro or battery storage is also dubious. We should be pursuing all avenues available to us.

Also, making a pure opportunity cost argument is a little weird as well. The investments are not purely fungible. That's why we should both give extensive resources to ramp PV and resources to ramp nuclear and resources to ramp p->g->p, because they're not the same resources.

France is evidence that putative economic buildouts of nuclear are not repeatable, if they were ever actually economical in the first place.

It is not an option we know will work. The inability of France to replicate their previous putative success means we can't take any of that for granted.

We have evidence that nuclear will NOT be economical at scale. The evidence is there in a cavalcade of disastrous experiences, even in places like France were experience supposedly, by your reasoning, would have told us to expect otherwise.

Well, France exists and is not bankrupt. France has managed to do it, and leads Europe in carbon output per unit of electricity, and will not be matched for quite some time.

"How is the intermittency gap actually bridged. Tell me. I WANT to know."

There are several different ways. Demand response is significant. Large users are already paid to reduce their usage during times of tight supply. It should be economical at some level to push that much further down the list. Some utilities today already do time-of-day pricing, so make it much more explicit and allow many more people to participate. The idea that we must allow anyone to use as much electricity as they want at any time is ridiculous.

For seasonal and time of day issues, the intermittency issue is mitigated by the fact that different technologies are strong at different times. Wind is most active at night. So the answer to "what do you do when the sun isn't shining" is in fact "install wind". Similarly, wind is weak in summer. Guess what? Summer has the longest daylight periods. So solar panels produce electricity for many more hours per day. "Use electricity during the day and use much less at night" is a reasonable solution. Again, the bullshit idea that we need to allow everyone to use all of the electricity that they want at any time needs to go die in a fire.

I like to point out that at the very worst you can keep existing nuke plants and nature gas fired peeking plants around for another 15-30 years. Which means you kick the solar and wind will never work because of storage 'problem' 15-30 years into the future.

And as you said a significant proportion of 'baseload' customers will chase price whatever it is.

>Wind is most active at night.

No it isn't! Wind speed goes down at night! Wind is also highly variable across seasons and across years. Wind and solar do not complement one another very well (though, geography permitting, they may - see Texas).

>the bullshit idea that we need to allow everyone to use all of the electricity that they want at any time needs to go die in a fire.

This is your problem. You're expecting that our energy use will go down and align with what solar and wind can do. This isn't going to happen. The population is growing. Energy use is growing faster than population is growing. Third-world has still decades of growth to go. Energy use will go up. Accept that, and internalize it.

Maybe if we had no options I would be amenable to hoping for lower energy use, but we have nuclear technology that can scale to our needs, is carbon-free, and has tiny land-use. All the alternatives have major downsides. Biofuels require thousands of acres of corn or whatever. Wind is terrible for birds, requires building high-tech machines (equivalent of jet-engines) with a lot of moving parts, needing lots of maintenance. Solar has huge land-use requirements. Both wind and solar contain rare earth elements which need huge mines to extract and we're not even sure we have enough of those to meet demand if everyone switches to those technologies.

Meanwhile, there's nuclear. All ready for a major renaissance, and people who purport to care about fossil fuel emissions are still spreading FUD about it.

> First off, yes there is battery technology to bridge the gap.

Not really, worldwide production capacity is several magnitudes below what would be necessary to buffer a large renewable rollout. The most realistic way to do it is natural gas, as they do in Australia.

Plus, current battery production requires materials that are highly problematic from an environmental standpoint.

> There are numerous markets with very high % of renewables already, and it turns out utility operators are very smart and know how to plan very well.

Which ones would that be? Look at Germany: Total failure to reduce CO2, high reliance on coal. Look at Australia: Supported almost entirely by natural gas. Those are the biggest rollouts of wind energy besides China, but you cannot trust any numbers coming out of China.

> Not really, worldwide production capacity is several magnitudes below what would be necessary to buffer a large renewable rollout.

Which definition of 'buffer' are you using here? Enough to supply day to day drops, or some kind of year-round system?

Wind and solar would need to scale up two orders of magnitude, and it's not hard to imagine batteries scaling along with them. How many more orders of magnitude would batteries need to scale up?

Current battery production is tiny, services small consumer electeonics and some cars. It's at least two orders of magnitude. Day to day drops are realistic, but buffering from summer to winter is out of question really.

> Current battery production is tiny, services small consumer electeonics and some cars. It's at least two orders of magnitude.

That is 100% fine. It only has to scale as fast as the power production. If they're both scaling two orders of magnitude, they should work hand in hand just fine.

> Day to day drops are realistic, but buffering from summer to winter is out of question really.

Good! Day to day is all you need. It's ridiculous to use batteries between seasons, and there are far better technologies to use.

Battery production needs to scale about two extra orders of magnitude- current production can't backup current renewables.

The current battery prices are reflective of relatively small spale, high value needs of consumer electronics industry and a nascent electric car industry. Hopefully the price will drop massively, like it did for solar panels, but currently we can't even produce enough for cars

I wholly agree with your start - let's do it. The best example we have so far is the Orkneys. Tiny, but a nett power exporter built on renewables, and managing easily. A proper example is sorely needed.

Kit out a nation with wholly solar, wind, hydro etc. Add whatever pumped storage and battery the grid might require. Start moving to modern standards of insulation and community heat and power schemes. Stable, secure, and cheaper heat and power.

If, as you claim, there is a gap in the capability of renewables (which I don't believe for a moment), we need to learn how large it is, as soon as possible.

I suspect it's only vested interests stopping us.

>The best example we have so far is the Orkneys.

Orkneys is a tiny (20k) region, that is connected to the national grid. That's how they solve their intermittency. That they produce excess energy during peak, is fine and dandy, but that's not what we're trying to solve here.

>Add whatever pumped storage and battery the grid might require.

Woah woah woah woah. You just yadda-yadda over the MOST important part. You know, the thing that makes solar/wind unworkable. Pumped storage requires very specific geography and huge land-use. It is not a general purpose answer. And there is no battery technology to power a modern city (much less a nation) for even minutes, much less weeks.

Now what?

>I suspect it's only vested interests stopping us.

No. It's not. It really isn't.

I specifically called out their being tiny. Which is why we need a larger scale example. Nevertheless, despite having the interconnect they are a nett exporter each year, and at the export capacity of that interconnect. Being tiny there is nowhere to put pumped storage, yet they are already using a smart grid managing household, and I think EV batteries. So yeah, they use the grid as storage.

Of course pumped storage, and other storage is a general purpose answer. You don't need 100% capacity to power a nation for weeks. Chances of no sun at all, no rain and empty rivers, and no wind across the whole British Isles, or Europe, including offshore? Nil. So now it needs an appropriate balance of sources, and storage. I don't know what that is in TWh, but I know with certainty it is not "running a nation for weeks".

In reasonable terms, some mix of new projects like Dinorwig, that can run for about 6 hours at max power, battery, managed battery and the more exotic like power to hydrogen - already in use in Orkney, and molten salt that can cover some period far less than weeks will be the right answer.

A house with a solar panel can be a net exporter. So can an island tied to a larger grid.

It is completely orthogonal to the intermittency problem mentioned.

The grid isn't "storage". And yes, Orkney is tiny, but it also needs proportionally less storage.

No, it really isn't. They are inseparable in building a smart grid of intermittent sources.

A house that is an overall exporter still needs coverage for the night time. Maybe household battery, maybe import from the grid. It does not need a battery capable of weeks or even an entire day.

A city needs some TWh capacity when solar is not functioning, some other capacity when wind is not functioning, etc. It's perfectly reasonable to import some of that from other parts of the country or region which aren't currently cloudy or wind-free, and export when there is excess. Storage needs to cover any shortfall, and some excess to cover growth and the unforeseen. It doesn't need to run for weeks assuming zero replacement for a period of dead calm, or assuming country or continent wide dead calm.

If you want every house or city a self contained island without grid interconnect, then your storage requirements ramp up markedly.

Sure, the covariance between solar and wind production at one site isn't 1; and the covariance between all the contributing sites for wind isn't 1. So it does smooth out to some extent. (To some extent-- there are practical limits on grid size).

However, it's inescapable that you need a whole lot of storage. As we conceptualize it now, the grid has to remain available during 1% and 0.1% events.

Again, your point is orthogonal to what was said. If someone grouses about storage, mentioning a net exporter provides zero information. Mentioning that my house is a net exporter does nothing to inform them.

Wind and solar produced electricity. Electricity is a subset of energy (around 20% i think)

Last summer in Denmark was amazing. The best we have had in a long time, the result was that the wind didn't blow wich meant no energy.

So Denmark had to buy their energy from Germany, another country who is all in on trying to use alternatives.

Of course that couldnt' deliver and instead they got energy from coal.

There is so much misinformation going on when it comes to how wonderful solar and wind is.

The reality is that they are less than 1% of the worlds energy production and not projected to be more than around 30% in 2040.

In short. You are as wrong as you can be with regards to your believe in wind and solar.

Hydro is better but only works in some places.

Solar growth projections vs reality: https://steinbuch.wordpress.com/2017/06/12/photovoltaic-grow...

Electricity can be used to replace all uses of energy we have today more or less economically. AFAIK anything but airplanes has replacements that are as good or better than the fossil fuel variant. Problematic are things like concrete and steel production, where we don't have good replacements yet.

Bear in mind that solar capacity and actually fulfilling electricity demand from that capacity are two very different things. The capacity factor of solar is between 20-30% as compared to >50% for fossil fuels and >90% for nuclear [1].

Hydrogen powered aircraft are hypothesized, but require lightweight hydrogen vessels. Maritime vessels can only be feasibly powered by nuclear power. The energy density of batteries is orders of magnitude less than fossil fuels, and sail boats cannot feasibly fulfill demand for shipping. There's a very strong aversion to nuclear energy, so we'll probably be burning fossil fuels in ships for a long time.

1. https://en.wikipedia.org/wiki/Capacity_factor#Capacity_facto...

Ships can probably be run off hydrogen, and if that is impossible for some reason you can always make synthetic fuels. Airplanes could also run off synthetic fuels, but since airplane emissions are actually a lot worse than just their CO2 output, that is not a good solution.

Hydrogen has good energy per kilogram, but bad energy per square meter even in its liquid form [1]. Liquid hydrogen is less than 10 times as dense as water.

Synthetic fuels either require considerably greater arable land and water consumption to grow biofuel, or the use of things like algae cultivation and accelerated decomposition. It's probably more effective on a $ / CO2 mass basis to just sequester carbon and keep using refined fossil fuels. Airplanes account for a single digit fraction of the CO2 emissions from transportation, though, as their mass and drag are both tiny as compared to cargo ships.

1. https://en.wikipedia.org/wiki/Energy_density#/media/File:Ene...

Reply to your post below, HN is not letting me respond:

Those synthetic fuels are effectively the same as biofuels. You're using energy to sequester carbon out of the atmosphere (or a body of water, in the case of algae based biofuels) and using that carbon to power a machine.

You can either do this by using electricity generated from another artificial power source, as in your example. Or you can do this by harnessing natural energy, like setting up transparent pipes to collect solar energy into algae or by farming biomass on land. Since most energy decarbonization plans assume modest energy consumption growth, and sometimes even an overall energy consumption reduction the former plan is less feasible than harnessing naturally occurring energy.

With synthetic fuels I don't mean biofuels, which I think are a terrible idea, but instead something like https://en.wikipedia.org/wiki/E-diesel

No, it can't be used for that and the size of the batteries even for those things it can be used for is a giant issue (and thus cost)

Solars capacity factor is around 20-30 or something like that. It's not even close to being a realistic deliverer and wind doesn't change that either.

I am not joking here. If you can point me to any solution that can economically power ex. the shipping industry using electricity please point me to it so I can invest in it right away.

The reality is that we are decades if not longer away from anything close to the dream scenario you read about everywere around you which becomes very very obvious the second you start looking for investment opportunities and is a good reason why it's primarily driven by politicians, not the market.

Investments in solar and wind are declining too because china is reducing its investments. If it was so great why wouldn't the private market just take over?

My guess is that in 5 years a lot of people are going to get a rude awakening when they finally realize they've been told dreams rather than reality.

But as I said. If you can point to actual solutions to these problems then please let me know so I can invest.

You say "economically" as if there was an alternative to stopping global warming. The shipping industry won't survive catastrophic climate change.

That being said, if you google around a bit you find a number of studies showing how 100% or close to 100% renewable energy can be achieved with today's technology. There is for example

http://energywatchgroup.org/new-study-global-energy-system-b...

or this (just for Germany)

https://www.ise.fraunhofer.de/content/dam/ise/de/documents/p...

I don't need to google around, I know the litterature and I know the difference between what can be speculated and what can be demonstrated :) So don't worry about that.

Fusion is theoretically possible that doesn't mean we are even close to it and neither wind nor solar will be able to deliver anything close to the amount of energy (not just electricity) we need.

Again point me to a concrete solution that is currently being developed and I will invest instantly.

With regards to climate change then, first of all, it's not going to be catastrophic not even IPCC thinks that. Second of all the climate has always been changing and giving us challenges with fossil fuel we've managed to combat most of that.

You live in a rich society BECAUSE of its use of fossil fuels not despite of it.

Nature doesn't give us a safe and friendly environment we make unsafe, it gives us a hostile and dangerous environment we then make safe.

Try and give me a single example of a scientifically demonstrated consequence of the climate changing we can't deal with today.

Phytoplankton is declining: https://www.nature.com/articles/nature09268

Shame they couldn't buy it from France.

That's why a lot of big power lines between European nations are being upgraded so the grid will become more flexible in the future.

Correction 3-4% in 2040!

In other words not even close to being a realistic alternative.

That's a fair argument. Allow to counter this with: how much of this modern economy do we need ?

- high distance vs local

- high output ? (we waste 30% of food, have tons of electronic waste too)

- high frequency vs calm

I'm not trying to troll you, I'm really asking people to consider how much of this feverish economy we need.

If we cut fossil fuel for most and keep it for those with too low solar input, how would be our current society ?

It annoys me to know end when people consider the world as a fixed absolute best. Especially since there are clearly flaws.

How about when a single centralized oil refinery gets bombed by an unhappy middle-eastern country and your global productivity drops 5%?

How about the fact that we know that fossil fuels and nuclear (and hydro and geothermal if the geography allows it) can actually power a modern economy? Is there a comparable example you can point to where solar or wind successfully replaced traditional power generators?

You don't have to convince me fossil fuels are shitty and need to be replaced. I'm with you. Tell me how solar/wind replaces those.

Batteries and building _more_ of it. Batteries work. We know how to store energy. And we don't need some perfect, uber efficient storage system yet to at least begin heavily investing.

Fossil fuels have an artificial advantage simply due to oil subsidies. Even Germany is 20% wind power already.

>Batteries and building _more_ of it. Batteries work.

Point me to a battery deployment that can store enough energy to power a modern reasonably-sized city for even hours at a time, much less days or weeks.

That Tesla battery deployment in Australia? It provides a few seconds of energy.

>We know how to store energy.

No. We don't. Not at the scale we need to power an economy. That's the problem.

>Even Germany is 20% wind power already.

Sure. And the rest?

Germany is signing multi-decade, multi-billion dollar deals with autocratic Russia to import their natural gas. Is that because they believe that wind and solar can fully replace fossil fuels? Or is that they know, that solar and wind have a hard ceiling on how much power they can provide and the rest needs to be bridged by burning natural gas, or coal, or biofuels (i.e. garbage, or corn, or whatever) to make it work?

> Point me to a battery deployment that can store enough energy to power a modern reasonably-sized city for even hours at a time, much less days or weeks.

https://electrek.co/2017/12/21/worlds-largest-battery-200mw-...

The battery’s purpose is to provide power during peak hours of demand, to enhance grid stability and deliver juice during black-start conditions in case of emergency. The system is expected to peak-shave about 8% of Dalian’s expected load when it comes online in 2020.

> Point me to a battery deployment that can store enough energy to power a modern reasonably-sized city for even hours at a time, much less days or weeks.

> That Tesla battery deployment in Australia? It provides a few seconds of energy.

Let's see.

129 Megawatt-hours.

The 20th largest city in Australia has about 90 thousand people.

One estimate says that if this battery is drained at the designed 100MW it can power 30 thousand homes. And there's 2.6 people per household. So if the battery was adjusted to drain at 115MW it would power that city for over an hour.

Another estimate is that Australia averages 10MWh per person per year, that's about 103 megawatts for 90k people.

So if we pick the 23rd largest city instead then we can supply 100% of the city's power with this single installation for well over an hour.

That's a lot better than "a few seconds".

You can't drain lithium ion batteries in "a few seconds" anyway.

And for that many people, it cost around a thousand dollars each. With electricity around 30 cents a kWh, you could take a third of that and install another hour of battery each year.

>So if we pick the 23rd largest city instead then we can supply 100% of the city's power with this single installation for well over an hour.

Color me unimpressed.

>That's a lot better than "a few seconds".

It's also a lot smaller than any city that matters. 90K people is more like a town (and small at that) than a city...

It would be seconds for a city with a few million people...

> It would be seconds for a city with a few million people...

Australia only has two of those.

If you get picky enough about what counts as a city, then the problem solves itself; they become irrelevant compared to the bulk of the population.

You don't need one facility to feed an entire city.

What matters are the per capita numbers. $1000 per head, lasts an entire hour.

Install 300 of those batteries and it will cover the entire country.

And "seconds" is still wrong.

Brisbane, Perth, and Adelaide. 3rd, 4th, and 5th largest cities in the entire country. If you feed one of them off 129 megawatt hours, it's somewhere in the low hundreds of seconds.

>What matters are the per capita numbers. $1000 per head, lasts an entire hour.

Australian GDP per capita is $53k. So a national battery deployment to supply overnight power is roughly 1/5 the GDP of Australia. But we need more than overnight storage, since we need to account for daily and seasonal variability. Estimates range at around 8-16 weeks of storage. This isn't even remotely in the realm of reality. For comparison, at the peak of World War 2, American defense spending was roughly 1/3 of GDP.

Come on man. This is all unicorns and rainbows.

You do not use lithium ion batteries for seasonal storage. Use something else, or build enough generation for the weakest season.

1/5 of one year of GDP is not unreasonable for a major component of energy infrastructure. It's not going to be built all at once. I can't find the exact numbers for Australia, but the US has a similar GDP, similar use, much cheaper electricity, and pays 6-8% of GDP for energy. That does include more than electricity, but it's all relevant expenditure.

A fraction of 20% of GDP, because it's across many years, is firmly inside the realm of possibility. If we had to double energy costs it would still be feasible, but that's overkill. We need less than that feasible amount to fund all the necessary construction.

>You do not use lithium ion batteries for seasonal storage. Use something else

Like what?

You think I'm saying these things because I hate renewables. I'm trying to understand what people are arguing for! So you say Lithium ion batteries shouldn't be used for seasonal storage. News to me. News to a ton of people who believe that Tesla battery site can scale to that level. What is the battery technology that can store enough energy for weeks at national-scale.

Maybe there is no battery technology? Then why are coming up with these examples that you know don't work! If you look at my original post that all I said is that there is no battery technology that scales to economy-size and therefore you need fossil fuel backup for solar and wind... Which part of that is wrong?

This is my frustration because regular people and experts just handwave the answers. Germany is all on in solar and wind and fighting climate change and is hailed as a model for the world and also invest billions into gas pipelines to Russia to provide them with huge volumes of natural gas for decades!!!

What the fuck is going on? I just want to know. I'll post something, told I'm wrong but nobody will post the answer.

Most of that is negated by the rest of the sentence you cut off.

If you build enough generators for the weakest season, then you don't need to store energy for seasonal variations.

It's an option that exists as a worst case, and it's not that bad. If you're extremely worried that all your renewable generation might fail for over a week then you can have backup fossil power plants that run an average of a couple days per year.

It's not cheap but it's not outrageously expensive either. It's entirely possible to afford if it was a priority. I might even argue that it's easy for the US to afford it, if we increased electricity prices to match Australia's...

But as for long term storage, there are a few options. Other kinds of batteries exist, and are in development. Producing hydrogen or other fuels is possible, and would be carbon neutral. Even if it has bad efficiency, we'd have tons of extra electricity during the good seasons.

> all I said is that there is no battery technology that scales to economy-size and therefore you need fossil fuel backup

Well that's not the post I was arguing with. The post I was arguing with was calling it impractical to store energy for a few hours!

If we can't store for a few hours, then we need a base load backup half the time.

If we can store for a few days but not more, then we need a base load backup 1% of the time.

Huge difference. We can do the former. We can maybe do seasonal storage, but it's the former that matters.

Those numbers are not very favourable, you need at least a night of backup, so like $10k per head for batteries alone.

Well, like I said, 30 cents per kWh gives you a huge budget. If you can add one hour of capacity per year, and the battery facilities last 30 years... seems affordable.

Also wind does not stop overnight. You don't need to supply all the power.

I was assuming 100% solar, but sure you could go for wind. There is the general game of how much overcapacity you are willing to build -> in traditional grids your generation is slightly exceeding you peak needs. However, in renewable grid you probably should build significantly more (>>2X) than your peak needs, and minimise your need for battery storage.

That gives funny dynamics, where for some days electricity prices could be 0 or even negative.

>and the battery facilities last 30 years

Try 10 to 15 years. And we've never even attempted to hold energy for days or weeks at a time in these large scale deployments.

> And we've never even attempted to hold energy for days or weeks at a time in these large scale deployments.

Wouldn't that greatly reduce the wear rate?

To be clear, fossil fuels are already insufficient to power a modern day economy without trillions of artificial subsidies.

We are not in a mode where we can wait to deploy perfect technology. We will also not be going solar 100% anytime soon, but perhaps in the next few decades. The atmosphere and ocean are already unhappy, and maybe if we also invest in carbon sequestration technology we can roll back a century or so worth of damage.

You're in this mindset that immediately it's all or nothing, and that's not the case. But we do need to start investing large sums of money now instead of making oil cheaper than it would normally be on a free market.

>To be clear, fossil fuels are already insufficient to power a modern day economy without trillions of artificial subsidies.

The subsidies are part of the economy too, so clearly fossil fuels are capable to power a modern day economy. Else the economy would have gone down (due to the subsidies cost).

The problem with solar/wind is that even with the same or larger subsidies we haven't yet solved many problems for powering a modern economy with them. Even if we had a huge budget to do so with just the proviso that no fossil/nuclear is used.

And that doesn't even include the problem of replacing the fossil fuel based infrastructure itself. We don't even have enough electric battery making capacity for double the insignificant amount of electric cars sold now for example, much less for replacing every gas based car with an electric equivalent...

The

Global oil production is artificially constrained, it could be increased substantially if producers weren't afraid that prices would tank.

Which demonstrates nicely how absurdly broken our dependence on fossil fuels is.

" Let's see how well solar does at night, or on a cloudy day, or during winters, or evenings, or early in the mornings."

Hi, I work in solar, specifically cell and panel design and construction and testing. You're so dead wrong in your assumptive non-answering statement that you might as well just bury yourself.

Signed ~someone with real semiconductor experience - what do you have?

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