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

sciencemag.org

11–20 of 432 posts

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

#11

Why lithium ion batteries — are they much cheaper to make than new gravitational potential (i.e. hydroelectric) storage systems?

For systems that only run for a few hours per day (4-6), battery systems are cheaper to build, faster to build, and far easier to site. There are only a few critical hours of peak demand in California, in the late afternoon/early evening.

For example, look at the demand graph here for yesterday (11 July 2019):

http://www.caiso.com/TodaysOutlook/Pages/default.aspx

Demand goes above 35 gigawatts at 3:30 in the afternoon and is back below that level by 7:00 PM, 3.5 hours later.

Battery systems are useful for shaving off that daily peak. They reduce the need to activate more expensive and more polluting open cycle gas turbines that have typically been used as peakers. It will be a few years more yet before solar plus storage systems can make a significant dent in the use of more efficient combined cycle gas turbine generation.

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

#12

Why lithium ion batteries — are they much cheaper to make than new gravitational potential (i.e. hydroelectric) storage systems?

Hydro can be extremely disruptive to ecosystems, and you also need a suitable site for it. It's very situational, from what I understand.

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.

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

#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 that's $374,000 per MWh of storage.

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

#15
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?

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

#16

> 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…

Does it at least use a TVM calculation? If so it's indeed quite misleading, considering that at max 1 cycle per day (e.g. solar) that's 6 years to spread the cost across.

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

#17
post #15
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?

This is possible only when you have a temperature _difference_ to work with. If it’s equally hot everywhere, you’re SOL. (Think heat death of the universe)

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

#18
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…

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.

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

#19

I wonder what the wider economic effect will be if the price of solar continues to improve and the fossil fuel industry can't find a way to remain competitive. Since some places are far more suitable for solar power generation than others, will those areas end up with a significant advantage in the cost of living? Could that in turn lead to a major migration of people and economic activity to those areas?

If you are talking about countries, cost of energy stopped being an important differential ages ago (except for some very specific niches, like aluminum refining).

If you are talking about cities, people will just build transmission lines.

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

#20
post #15
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?

Because E To get energy from heat, you need a hot end and a cold end. The more difference between the two, the more energy you can extract. Extracting energy from small temperature differences is very inefficient. Temperature is measured from absolute zero for this.
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