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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

#71

Post by blake1 »

laser wrote: post #62

How is the battery storage only $0.013 per kWh? Is that a misprint and they meant $0.13 per kWh? Or is there some fancy accounting where they're storing only a small percentage of the total energy output and giving a diluted price with the partial storage cost spread over the total output? Or is it truly possible with massive scale to achieve battery costs this low? I can't see how this adds up without some sleight o…

Later in the article they clarify that the batteries cost $0.187/kWh. However, the owner of said battery will be able to sell energy storage to the grid operator. I also assume that there is a synergy, in that the solar side of the installation is more valuable.

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

#72

Post by onetimemanytime »

jdhn wrote: post #67
onetimemanytime wrote: post #59

Earlier quoted context omitted.

>> The average summer high in LA was in the mid 70s during the 1950s. Now it’s in the high 80s and sometimes hits 100+. 10 degrees plus in changes over a few decades?

I bet it's due to the heat island effect due to the proliferation of roads and parking lots.

That I can see. No shade + concrete is a nightmare. Plus wind is probably limited due to buildings.

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

#73

Post by dmix »

krferriter wrote: post #23
ivanhoe wrote: post #18

Earlier quoted context omitted.

There should be also more focus on proper thermal insulation of houses in warm climate, which is something that is not often mentioned. Lots of energy gets lost on AC simply because heat easily enters the houses.

Yeah I'm renting a house in central NC and May-September our power bill skyrockets from AC. The windows are not insulated at all and we have a lot of them. Even the floors, walls, and ceilings leak heat like crazy, you can feel it just putting your hand close to the wall or ceiling. We run AC to get it down to 76F and it's still crazy expensive and using a lot of unnecessary power. We need to encourage insulation, es…

I have the opposite problem living really high up in a condo. The heat from units below us travel upwards and in the summer I can open the door and get free cooling effect.

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

#74

Post by laser »

F_r_k wrote: post #65
laser wrote: post #62

How is the battery storage only $0.013 per kWh? Is that a misprint and they meant $0.13 per kWh? Or is there some fancy accounting where they're storing only a small percentage of the total energy output and giving a diluted price with the partial storage cost spread over the total output? Or is it truly possible with massive scale to achieve battery costs this low? I can't see how this adds up without some sleight o…

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 aware. That makes me suspect they're actually only storing like 10% capacity then amortizing the cost of storage across total output, as I can't understand how else the numbers add up. Any ideas?

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

#75

Post by sp332 »

mikestew wrote: post #25
driverdan wrote: post #13

> In March, an analysis of more than 7000 global storage projects by Bloomberg New Energy Finance reported that the cost of utility-scale lithium-ion batteries had fallen by 76% since 2012, and by 35% in just the past 18 months, to $187 per MWh. I hate it when they list battery prices this way, it's very misleading. That's the amortized cost of $187 per MWh cycle, not the battery's upfront cost. Assuming 2000 cycles…

I hate it when they list battery prices this way, it's very misleading. Misleading to some, flat-out useless to others. The replacement cost of the 24KWh battery in our Nissan Leaf is about $5K. So I'll take two of those $187 MWh batteries, please. Oh, of course they're not speaking the same language as I am with that kind of price difference. But then I guess I don't know what in the hell they're talking about if no…

Person A: I'd like you to store one megawatt-hour of electricity that I will give you, and then later, I want you to give that electricity back to me.

Person B: Certainly. That will be $187.

It's not the cost of the battery. It's the cost of storing and releasing one megawatt-hour of electricity once. This has to pay for the capital cost over time, as well as overhead and depreciation.

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

#76

Post by ivanhoe »

ausjke wrote: post #15
Animats wrote: post #7

$0.02/Kwh for the solar part is pretty good. A reasonable short-term goal: get 100% of US peak air conditioning load south of 37° N on solar. That's the line from the Virginia/North Carolina border west to central California. Peak solar power output and peak air conditioning load line up pretty well, so that doesn't need storage. Storage is more of an issue for wind, which varies about 4:1 over a day over large areas…

I have been wonder why can't we convert outside heat into indoor cooling naturally, i.e. in Texas can we convert summer heat to AC power in real time for at least each residence house?

That's not possible, but geothermal energy is a passive way of cooling that actually works (to some point). Install pipes sufficiently deep under the surface and drive air through them and soil will cool the air for you - and because its temperature is almost constant throughout the year you can both cool and heat the greenhouses and barns and even homes this way with very little extra energy (just electricity for fans to move the air, and even that can be reduced to work passive for heating as the hot air climbs up the pipes on its own)

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

#77

Post by merpnderp »

laser wrote: post #62

How is the battery storage only $0.013 per kWh? Is that a misprint and they meant $0.13 per kWh? Or is there some fancy accounting where they're storing only a small percentage of the total energy output and giving a diluted price with the partial storage cost spread over the total output? Or is it truly possible with massive scale to achieve battery costs this low? I can't see how this adds up without some sleight o…

I'm guessing if they don't count depreciation and charge the batteries when the price is negative, it might make sense. But otherwise that is an astounding claim backed by zero evidence.

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

#78

Post by codesushi42 »

astazangasta wrote: post #48
codesushi42 wrote: post #40

Earlier quoted context omitted.

Exactly, this is why steam boiler engines became obsolete, because you can burn gas at a much higher temperature than boiling water. Lower temp can only be viable if you reduce the work needed to run the engine, and can still output the needed work/energy. This is related to why work and heat are both measured in joules.

No, this is not right. Most power generation is done by steam in the US (85%). Steam can get much hotter than boiling water, and it is cheap and makes no waste.

That doesn't have to do with temperature, it has to do with the efficiency of the engine.

Gas burns at a much higher energy than steam, so it's much easier to extract more energy with less fuel, making for a smaller form factor.

I should clarify I was talking about an engine here. Not a power generator.

What I said is correct though. You can compensate for lower temperatures with a more efficient engine & energy conversion, and of course more fuel/input.

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

#79

Post by opencl »

jstsch wrote: post #31
krferriter wrote: post #23

Earlier quoted context omitted.

Yeah I'm renting a house in central NC and May-September our power bill skyrockets from AC. The windows are not insulated at all and we have a lot of them. Even the floors, walls, and ceilings leak heat like crazy, you can feel it just putting your hand close to the wall or ceiling. We run AC to get it down to 76F and it's still crazy expensive and using a lot of unnecessary power. We need to encourage insulation, es…

I was wondering about this the other day. In NL, insulation has been part of the building code for ages. With stronger requirements every decade or so. Insulated windows have been required since the 80ies for new houses. Now it’s triple pane krypton glass. Is this not the case for the USA.

The US has insulation requirements, it varies a lot state to state but new housing generally has at least decent-ish insulation. The main issue is that there is a lot of very old housing stock in the US. As of 2015 the median house was 37 years old and 40% were over 45 years old. In the area I live the vast majority of the houses were built in the 40s or 50s, though most people have done some amount of insulation retrofitting.

http://eyeonhousing.org/2015/08/the-aging-housing-stock-2/

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

#80

Post by m463 »

Animats wrote: post #7

$0.02/Kwh for the solar part is pretty good. A reasonable short-term goal: get 100% of US peak air conditioning load south of 37° N on solar. That's the line from the Virginia/North Carolina border west to central California. Peak solar power output and peak air conditioning load line up pretty well, so that doesn't need storage. Storage is more of an issue for wind, which varies about 4:1 over a day over large areas…

> $0.02/Kwh for the solar part is pretty good.

What's terrible is that PG&E charges the end customers $0.28-$0.42/kwh even though it purchases even the most expensive wholesale power below 5c/kwh

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