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

sciencemag.org

91–100 of 432 posts

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

#91
post #66

Maybe this isn’t a problem, but I am curious about how and where all those solar cells and batteries will be disposed at the end of their usefulness?

solar panels (the panels themselves) are made of silicon, which is sand, so aren't a huge concern.

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

#92
post #50

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…

If the window is in the sun, your major problem is unlikely to be window insulation. It’s solar heat gain. Sunlight carries a lot of power — about 1 kW per square meter. If your window lets all of that power in, then your AC needs to consume a couple hundred watts to send it back out again. What you need are windows with low solar heat gain coefficients (SHGC), which is mostly independent of insulation. Or you can ge…

> What you need are windows with low solar heat gain coefficients (SHGC), which is mostly independent of insulation. Or you can get window treatments that are shiny on the side facing the window.

In the desert by me people use substantial awnings on the exterior putting the windows in shade. It's a lot cheaper than fancy window treatments and in my experience far more effective. Provides more space to mount solar panels too.

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

#93

> the cost to decarbonize the U.S. grid alone would be $4.5 trillion They make this sound like a lot but that strikes me as actually pretty cheap. I don't think that number can be right. Edit: I mean seriously think. The F-35 has cost us 1.45 trillion dollars so far. That's roughly 1/3 of the price they're asserting here. Localizing our entire energy dependence has got to have some serious national security benefits.…

There are other limitations as well. Amount of lithium available, # of cycles before you have to replace the batteries, and so on.

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

#94
post #74
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…

> Any ideas?

Yes, there are two things that probably contribute here.

One is (as you guessed initially) "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." The majority of the solar generation can be consumed immediately without taking a trip through the battery. The battery capacity is needed to serve peak demand periods in the late afternoon/early evening, which last just a few hours.

The other is that you are probably lowballing the number of charge/discharge cycles at 2190. Unlike EV batteries, stationary batteries for grid demand don't ever need to "supercharge" at high rates or rapidly discharge for high acceleration. Careful moderation of charge/discharge rates can give double or more lifetime compared to identical batteries that undergo fast charging and discharging.

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

#95
post #56

Imagine our energy is solar 90%, don't we lose some risks diversification here just in the case if the state of affairs with the global sunlight conditions will change drastically?

If global sunlight conditions change drastically, we're probably screwed regardless of how we're generating our power. Think crop failures, ecosystem collapse etc.

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

#96

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

Well depends on the timeframe you are looking at. Hydro can do a lot more cycles than li-ion batteries.

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

#97
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…

You are probably right, but home solar has a few advantages. You already have the space for it. And you don't need to transport the energy anywhere.

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

#98
post #80
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

Typical PG&E rates are US$0.12/kWh, which includes not only buying the energy (at prices ranging from -$0.05 to $1.50 or more, depending on supply and demand) but also maintaining and constructing the transmission and distribution systems, as well as incidental additional costs like black start capacity, loan interest, and investor profit.

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

#99
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…

About a decade ago the US tax code gave rebates for improving homes to be more energy efficient. I think this started in Bush & went through Obama.

I know a lot of people who upgraded windows & insulation.

Many also did geothermal heating. I've heard from some trades people a lot of negatives about this one though.

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

#100
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…

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