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Giant batteries and cheap solar power are shoving fossil fuels off the grid

sciencemag.org

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Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#151

Post by Obi_Juan_Kenobi »

laser wrote: post #74
F_r_k wrote: post #65

Earlier quoted context omitted.

It's the marginal price of storing a kWh of energy. Not the price of the battery capacity itself

Right, I get that—but still don't get the math. Let's say they're buying this capacity at $300 per kWh of capacity, that the batteries last six years on average with a daily cycle, for a total of 2190 cycles. Amortizing that $300 kWh cost over 2190 cycles is $0.137 per kWh. In other words, holding the other constants the same, this company is suggesting $30 kWh batteries, which is just not yet possible as far as I'm…

The mythical $100/kWh figure for car batteries is for the pack cost, not the cells. Much of that cost is focused on a compact, lightweight solution for cell cooling, voltage balancing for ~100 batteries in series, etc.

Utility installations have much cheaper solutions for cooling, the balancing is much easier with lots of parallel cells, and even the chemistry benefits from smaller charge/discharge currents.

We're not down to $30/kWh yet, but we're not that far off. Certainly well below $300.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#152

Post by jayd16 »

rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

Even if something is profitable it might not be worth the risk, opportunity cost, or capital investment.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#153

Post by TallGuyShort »

rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

* It's as cheap as it is for residential solar because of government subsidies. Ultimately a subsidy just means somebody else is paying for it, so this falls apart at scale when you're talking about something that everyone will use somewhat equally.

* I looked at residential solar and it looked to me like if I paid it off for 5 years at the rate that it saved me money, I would be further behind than if I had waited 5 years and solar panel prices continued to decrease. So why buy now? They decrease in value faster than they save money. It wouldn't have been a financially motivated decision.

* The solar company said they could eliminate my electricy bills if I bought solar, and they did a bunch of upgrades like improved insulation. The insulation had a much higher return on investment so I did that anyway - it's easier for me to simply need less energy than to replace all my energy sources (similar to a lot of environmental issues, IMO - we could overhaul recycling infrastructure, or I could just buy food that results in less non-compostable waste).

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#154

Post by bufferoverflow »

rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

People install solar or various reasons. The main ones I noticed are:

1) Long-term climate change effects

2) To reduce the electric bill

2a) To blast the AC when the sun is the brightest.

But you also have to account for land costs, as large-scale solar installations require large fields of panels.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#155

Post by kragen »

barneygumble742 wrote: post #119

> Wood Mackenzie estimated the cost to decarbonize the U.S. grid alone would be $4.5 trillion The 2017 tax cut cost $1.5 trillion. I'm starting to suspect that priorities are being misplaced.

The tax cut cost the government $1.5 trillion, but provided that same $1.5 trillion directly to the taxpayers. It was a pure transfer, not a cost in the sense that we're talking about here, which involves the consumption of natural resources and human labor, for which the dollars are merely a numerical representation. A better comparison would be the cost of some boondoggle defense program, or the prison system, or unemployment.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#156

Post by rossdavidh »

Good news: non-carbon energy sources will, faster than most of the world currently thinks, force carbon energy sources off the market. This has already started to happen with coal.

Bad news: Well the Left may lament the fact that it will not be due to any change of heart or international cooperation, it will just be due to mercenary calculations of cost, and technology. But all of us have to consider what will (not may, will) happen to places with very oil-dependent economies, when oil goes the way of coal. Imagine Saudi Arabia in the state that Venezuela is in right now.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#157

Post by ZeroGravitas »

dv_dt wrote: post #138
ZeroGravitas wrote: post #113

Earlier quoted context omitted.

I can't tell if the duck curve thing is intentionally misleading, but people all seem to jump to the wrong conclusion. The demand isn't greater in the evening, the relative demand, after you subtract all the energy provided by solar, is in the evening, during periods of the year when demand is low but solar supply is high. It's like someone cured cancer and then someone came up with the llama curve, showing that some…

Perhaps a better statement would be that the duck curve represents unmet need in the evening once solar is in the mix. Without storage, you can add more solar, but into the evening that can only help so much without also adding some amount of storage to offset that available power into a time it is still needed.

It's generally not even unmet need. Usually the duck curve hits at times well below the actual annual peak so there's enough generation capacity available.

But some of that capacity is slow to respond and need time to ramp up, which may be longer than the time taken for solar to ramp down.

The simple solution to this is to start those slow to ramp sources a little earlier and throw away their excess energy output.

Obviously that's wasteful, but as long as the generation mix is overall cheaper and less carbon intensive with solar added, which it is, then it's not a big deal. And obviously as soon as you add storage then they can help these sources ramp more efficently at first and expand to replace them entirely over time.

All in all it's one of the least problematic problems that ever got its own name.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#158

Post by litany »

rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

So the thing is the economics of rooftop solar are a lot different than power station solar. The DOE has public data on how much utilities pay for electricity. In a market like mine, Southern California Edison isn’t an electricity generator, they buy power at about $0.02/kWh but then they sell it to the residential consumer for up to $0.32.

So clearly it’s a very different calculation. Regardless of that generators are building large scale solar arrays to sell power to the utilities at very much lower rates than what a rooftop owner pays to generate their own power. It’s just the rooftop owner can bypass a lot, and potentially all, of the utility and grid fees which are >90% of the cost. The other thing is that many utilities are hugely subsidizing this with net metering policies, which basically means the utility is acting as a huge battery for only the grid connection fee which, depending on the market, can be as low as $15 a month. Which basically seems to make products like the Tesla Powerwalls a really tough sell. Why pay $5000 for a tiny powerwall when, assuming you want grid connect anyway, the utility will be a way bigger powerwall for free?

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#159

Post by Obi_Juan_Kenobi »

cmoscoe wrote: post #45
Animats wrote: post #12

Earlier quoted context omitted.

very situational Yes. You need a mountain lake and a low level lake close to each other, and the lakes aren't useful for much else because the water level goes way up and down every day. The US has 10 pumped storage plants bigger than a gigawatt, and few attractive sites for more.

I've hear the Hoover Dam proposed, and theoretically any existing dam could be converted? Just need to pump some water back upstream when there's excess load in the system. Here in Canada a lot of our energy is hydroelectric and I know there's a lot of talk about this sort of solution in Quebec.

> Just need to pump some water back upstream

In this situation, you'd simply never let the water flow through in the first place. This amounts to releasing water while generating energy, only to pump it back. The net result is just a lot of wasted energy.

Pumped hydro requires two reservoirs. There's no way around it.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#160

Post by ajross »

rossdavidh wrote: post #156

Good news: non-carbon energy sources will, faster than most of the world currently thinks, force carbon energy sources off the market. This has already started to happen with coal. Bad news: Well the Left may lament the fact that it will not be due to any change of heart or international cooperation, it will just be due to mercenary calculations of cost, and technology. But all of us have to consider what will (not m…

Cynically: to first approximation no one lives in Saudi Arabia. Even if it devolves to a Venezuela style anarchy, we'd still be more worried about Venezuela.

Practically: Saudia Arabia is an oil source. Petroleum fuels are going to be with us forever. It's coal (first) and gas (eventually) which are being displaced by better electrical generation options. But if you want to fly an airplane, you really can't replace the savings you get from not having to carry 2/3 of the reaction mass on the vehicle. Oil wealth will be the very last to go, likely well after they're tapped out anyway.

And politically: "the Left" you postulate doesn't really exist anyway. You can be a raving socialist and still be pleased that technology solves your problem. You can be a market centrist and still believe that carbon regulation is a good idea.

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