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Falling lithium-ion battery prices to drive rapid storage uptake

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Re: Falling lithium-ion battery prices to drive rapid storage uptake

#11

Post by zAy0LfpBZLC8mAC »

merpnderp wrote: post #3
nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

I would think that for that use case, using thermal storage should be more efficient? Don't store electricity to run AC later, but run AC to cool down water or the ground beneath your house or something, and then cool your house with that later.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#13

Post by epistasis »

Gracana wrote: post #9
epistasis wrote: post #7

Earlier quoted context omitted.

GW is, however, a characteristic of an energy storage system, and just a valid and important measurement as the amount of energy it stores.

The maximum output is interesting to know, but if you asked how much my car's fuel tank held and I told you "100mph," you'd be understandably confused.

But we're not talking about cars, we're talking about the electrical grid.

In the current stage of the grid and storage, storage capacity is used not for long duration transmission of energy, but shorter term filling in of power gaps. In the past few years that's been frequency regulation, and now the replacement of peaker plants, or instantaneous response when waiting the 10-15 minutes for a peaker plant to come online.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#14

Post by EngineerBetter »

merpnderp wrote: post #3
nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

Wow - that's a crazy amount of energy. As a Brit who's never been the south of the US, is that figure really true? 100kWh is about 300 miles in a Tesla, or boiling a kettle constantly for about 30 hours.

If that's really accurate, then I'm staggered at how much energy folks must be using to keep cool, and makes my efforts at saving energy seem paltry in comparison.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#15

Post by cobookman »

zAy0LfpBZLC8mAC wrote: post #11
merpnderp wrote: post #3

Earlier quoted context omitted.

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

I would think that for that use case, using thermal storage should be more efficient? Don't store electricity to run AC later, but run AC to cool down water or the ground beneath your house or something, and then cool your house with that later.

Or build something like an Earthship (http://earthship.com/). I know that these can air condition a house in New Mexico through geothermal heat transfer, however no idea how they handle the more humid summers of the South East.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#16

Post by dougmwne »

Someone wrote: post #6
nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

Why wouldn't recycling be an option? Chances are that, if large batteries become commonplace, it will be cheaper to mine lithium from used batteries than to do so from the earth because they will have very high lithium content. Also, covering 1/3 of daily use seems low to me. It wouldn't get one through a few windless winter days with dense cloud cover, for example.

Is it possible that perfect is the enemy of good here? You could choose a lower ratio of battery storage to average use and just use non-carbon neutral peaker plants for the few days in winter where there's a shortfall of renewable energy. Still a huge boost to renewable energy, still a huge reduction in carbon emissions.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#18

Post by ptero »

epistasis wrote: post #7
fenwick67 wrote: post #4

> By 2025, the world’s base of cumulative installed storage capacity will reach 52 GW, IHS Markit says, up from around 4 GW today. Last year, 1.3 GW of grid-connected storage was deployed globally, and this rate is poised to accelerate to 4.7 GW a year by 2020, and 8.8 GW annually by 2025. GW is not a unity of energy storage capacity. It's a unit of power.

GW is, however, a characteristic of an energy storage system, and just a valid and important measurement as the amount of energy it stores.

Maximum discharge speed (which is one of the very few storage characteristics I can think of to be measured in GW) is pretty much irrelevant for storage systems. Add a few quick discharge capacitors that cost almost nothing and boom -- your max discharge speed shoots through the roof (but speed goes down for a very short time).

Maybe sustained charge speed is a (little bit) more meaningful thing you can express in GB.

I am with the parent -- this is either a typo or a journalist quoting something he knows nothing about (what's that "h" in GWh? Strange capitalization; probably a typo; let me strike that).

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#19

Post by Beltiras »

nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

There is another way of thinking about the economics of this. IIRC the typical price is 12 cents per kwhr. You would need to utilize the battery in sold energy no less than 2000 cycles just to break even. About 5 1/2 years of constant monetized operation (which is a ludicrous proposal). And this assumes no cost on the energy production side.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#20

Post by 2sk21 »

EngineerBetter wrote: post #14
merpnderp wrote: post #3

Earlier quoted context omitted.

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

Wow - that's a crazy amount of energy. As a Brit who's never been the south of the US, is that figure really true? 100kWh is about 300 miles in a Tesla, or boiling a kettle constantly for about 30 hours. If that's really accurate, then I'm staggered at how much energy folks must be using to keep cool, and makes my efforts at saving energy seem paltry in comparison.

I live in New Jersey and just had solar panels installed on my roof. Peak power is about 7.8 KW. On clear days, power production in the summer is about 50 kWh

I have been keeping daily logs this summer and find that my daily power consumption swings between about 25 kWh on cool days to 65 kWh on really warm days. Definitely a lot lower than 100 kWh mentioned previously.

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