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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

#321

Post by zelon88 »

mfgs wrote: post #239
zelon88 wrote: post #236

Seriously! I'm an old time R/C enthusiast who romps frequently and still buys a toy here and there. I got out of R/C for a little bit so the last pack I bought was a 4,200mah 7.4 volt LiPo from a tiny mom+pop manufacturer. The pack is well taken care of and probably 7 or 8 years old. It's time for a new one. I just looked up a replacement battery by the same manufacturer and their 7.4v LiPo's are up to 22,000 mah! Th…

Is there a theoretical limit to (current generation) battery capacity, like there is with solar panel power output?

Also, it's important to note that batteries don't generate power. They store power.

Literally. You pump electrons into them and they hold onto them internally until they can be released again. Think of it as a water balloon for electrons.

You create a vessel which is capable of efficiently containing electrons. Then you pump electrons into it and hope enough of them stick to be worthwhile. This is battery technology.

Different battery technologies have different characteristics. Nickel batteries usually have some form of "cell memory" where the cell will store "stale" electrons indefinately, and lose the ability to release them. These electrons can become "trapped" inside the battery and reduce it's capacity.

Likewise the chemical composition of lithium batteries makes them extremely volatile. This means that if you were to completely remove all electrons from the cell it would forget that it is a battery and refuse to store future electrons you try to pump into it. You also have to balance each cell in a lithium pack, else they will become uneven and one could possibly become completely empty (killing the cell).

Likewise, when a nickel cell loses all it's electrons it is still possible to "zap" the cell back to life with a large jolt of electrons. Some of which stick, some do not. Sometimes this results in the battery "waking up" to accept more electrons. Sometimes it doesn't, and a 6 cell (7.2v) nickel battery will have to be dissected to replace the bad cells.

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

#322

Post by kragen »

floatrock wrote: post #246
brownbat wrote: post #228

Earlier quoted context omitted.

I'm a big fan of that study. It suggests there may be an opportunity for a company to push rooftop solar for big strip malls and other large footprint single owner buildings - they aren't utility scale, but the install efficiencies make them pretty competitive. The incentives would be tricky, since the owners are less likely to be paying for utilities than the leaseholders...

https://www.wundercapital.com The problem with commercial solar is the cost of the financing. Home solar is on par with a car loan, banks know how to do that with personal credit scores. Utility scale solar is the realm of private equity. Something like a strip mall is a weird in-between that requires enough manual review that the cost to do all of the risk analysis that financing requires kinda outweighs the potenti…

On the contrary, personal loans from banks routinely charge much higher interest rates than commercial paper. Think about the interest rate on a money market account, which consists of bonds. That's the rate PG&E is going to pay if they float a bond issue to build a solar power station. Large companies, particularly including electric generation utilities, can also get loans from banks at similarly low interest rates.

This is precisely the genius of SolarCity: they were able to use the low interest rates banks would charge them to install solar power on people's houses at a much lower cost of capital than the same banks would have charged the same homeowners without SolarCity's intermediation.

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

#323

Post by kragen »

ZeroGravitas wrote: post #178
litany wrote: post #158

Earlier quoted context omitted.

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 a…

Most research suggests that net metering is underpaying the households that deliver it. This seems very counteri tuitive to people, but remember you're paying an average cost. Gas peakers can cost thousands of times that when load is high. If you use AC then solar and high demand are correlated. At the extremes that means building a whole new powerstation that might only be used for literally hours per year.

We're talking about an average net-metering cost of about US$0.12/kWh, right? That's 3.3¢/MJ in SI units, US$120/MWh in the units used in most real-time electrical markets. LMPs do sometimes get as high as US$120/MWh and even higher — I've seen US$160 at times — but never anywhere close to US$12000/MWh, as your "cost thousands of times that" comment suggests. (US$40 is more typical, and sometimes prices go negative, so you can get paid to burn energy.)

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

#324

Post by scotradamus »

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…

Worked as a physicist at LANL on energy related issues. Biggest problem is not energy production, it is energy storage.

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

#325

Post by austhrow743 »

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…

>If its financially advantageous to install solar on your roof, wouldn’t it be greatly more financially advantageous (given the main cost for solar installation is the labor) for energy companies to install solar at scale?

This actually mirrors my thoughts on house ownership as an investment as well.

Every house I've ever rented has been privately owned by an individual and either managed by them or a company that manages tenants for them but has no equity stake. It's always struck me that if residential properties were such a great investment, these companies would move in to it rather than give up supposedly great returns for no reason. Or large financial institutions would buy the properties and then have the rental management companies as clients rather than a host of small time investors.

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

#326

Post by astanway »

kragen wrote: post #323
ZeroGravitas wrote: post #178

Earlier quoted context omitted.

Most research suggests that net metering is underpaying the households that deliver it. This seems very counteri tuitive to people, but remember you're paying an average cost. Gas peakers can cost thousands of times that when load is high. If you use AC then solar and high demand are correlated. At the extremes that means building a whole new powerstation that might only be used for literally hours per year.

We're talking about an average net-metering cost of about US$0.12/kWh, right? That's 3.3¢/MJ in SI units, US$120/MWh in the units used in most real-time electrical markets. LMPs do sometimes get as high as US$120/MWh and even higher — I've seen US$160 at times — but never anywhere close to US$12000/MWh, as your "cost thousands of times that" comment suggests. (US$40 is more typical, and sometimes prices go negative,…

RTM prices in ERCOT can easily spike to the price cap of $9000/MWh during bad days: https://www.spglobal.com/platts/en/market-insights/latest-ne...

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

#327

Post by rebuilder »

TheSpiceIsLife wrote: post #279
namibj wrote: post #275

Earlier quoted context omitted.

There are many things you can defer, even at home. Mostly A/C related, but stuff like a self-cleaning oven or a clothes dryer doesn't need to run in the instant, necessarily. The dryer might be able to wait a few hours once the clothes are a bit dry (due to mold and such), as it needs to be ready when you get to it in the morning/afternoon. Until then, it only needs to prevent the clothes from water damage. The oven…

I don't need to defer anything, as I'm on a flat rate. I don't like peak metering, as it would forces me to micromanage things in a way that doesn't work for me. I don't have a clothes dryer, they use too much energy. I just hand my clothes on an indoor clothes airer and blow a fan on them. I usually leave the heat pump set to 16 degrees C while I'm out, the combination of mild air temp and the fan dries most of my c…

It seems odd that you worry about the energy a dryer uses, yet set your thermostat to 16 degrees when you're not even in.

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

#328

Post by pauljurczak »

sp332 wrote: post #75
mikestew wrote: post #25

Earlier quoted context omitted.

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.

Fine, except that the author uses "cost of utility-scale lithium-ion batteries" term instead of "cost of energy storage" you are referring to.

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

#329

Post by cstrat »

sien wrote: post #284
aussiegreenie wrote: post #222

Earlier quoted context omitted.

You are correct but will talk about Australia. Australian rooftop solar is less than half the US prices. A 6.6 kW system installed retails at(AUD 2700 /USD 1870) and yet we have some of the most expensive electricity in the world at USD 0.25 per kW-h. In many places, 1 in 3 houses having rooftop solar. We have over 9GW currently installed and increasing at 1.5GW per year. All this new production is taking market shar…

A quick search gives figures of AUD 5-7K for a ~6KW system. https://www.solarchoice.net.au/blog/6kw-solar-pv-systems-pri... https://mcelectrical.com.au/blog/what-size-solar-system-do-i... https://solaray.com.au/6kw-solar-power-system-price-output-s... (The last one suggests that cheap 6KW systems are junk)

There is a lot of negotiation room with solar installs. I paid just shy of $7K AUD for a 8.2kW Fronius inverter with 9kW worth of Suntech panels. The solar credit scheme contributes quite a lot of money to the installers so subsidise the setup. I checked wholesalers and I think the materials were worth more than the $7K AUD.

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

#330

Post by kragen »

basicplus2 wrote: post #304
colechristensen wrote: post #207

Earlier quoted context omitted.

I wonder how people would feel about ethanol plants fired by wind farms. The one built near my family home is coal fired and the idea of growing crops to be turned into car fuel is ... less appealing. But if you had electric or ethanol powered tractors growing biomass to ferment and distill into more ethanol with a plant fired with wind, maybe there are some different environmental considerations there. For one it wo…

Ethanol is highly corrosive, damages engines and fuel lines, is hydroscopic which exacerbates above and more problems, has even short term storage problems let alone long term, thats why its only ever used blended and is very toxic, in fact it is a nightmare fuel really.. bio diesel on the other hand has none of these problems. https://www.government-fleet.com/157454/storing-dispensing-u... https://www.cfact.org/2014…

Almost everything you said is precisely opposite from the truth.

Ethanol is less corrosive to metals than even pure water, although (like gasoline) there are some plastics that it can dissolve; some of these plastics were used decades ago in some cars, including in their fuel systems, when blending ethanol with gasoline was uncommon. Its hygroscopic (not "hydroscopic") nature is a reason that people have been adding it to their gas tanks for many decades, to safely get the water out ("HEET" is a common brand name in the US), although it's true that each teaspoon of ethanol can only dissolve a small amount of water before becoming immiscible with gasoline. It's very chemically stable, unlike gasoline, which can polymerize into "varnish," and it's easier and safer to store than gasoline, although it does need to be stored without access to too much air so it doesn't absorb water. It's so nontoxic that people drink it recreationally, which is a major industry in most countries, although this doesn't seem appealing to me. And, unlike gasoline, diesel fuel, or biodiesel, you can put out ethanol files with water. These are some of the reasons it's been used as a fuel alone, as well as blended, for centuries, and many cars in countries like Brazil are able to run on pure ethanol, despite its lower energy density.

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