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CO2 batteries that store grid energy take off globally

spectrum.ieee.org

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Re: CO2 batteries that store grid energy take off globally

#151

Post by hunter2_ »

SigmundA wrote: post #142
hunter2_ wrote: post #134

Earlier quoted context omitted.

So when I torque all 20 of my car's lug bolts to 120 n-M, I've exerted 2/3 of a W-h? So if it takes me 4 minutes, I'm averaging 10 watts? That's neat. I wonder what the peak wattage (right as the torque wrench clicks) would be; it must depend on angular velocity.

Newton meter as a unit of energy is not the same as the newton meter unit of force for torque. The energy unit meter is distance moved, while the force unit meter is the length of the moment arm. This is confusing even though valid, so the energy unit version is rarely used. You can exert newton meters of force while using no energy, say by standing on a lug nut wrench allowing gravity to exert the force indefinitely…

Ah! I guess that explains the "f" for "force" in the imperial abbreviation "ft-lbf", to distinguish it from work. I wonder if there's ever been an analogous variant for metric such as "Nmf"...

Re: CO2 batteries that store grid energy take off globally

#152

Post by gpm »

B1FF_PSUVM wrote: post #115
nayuki wrote: post #109

> The tried-and-true grid-scale storage option—pumped hydro [--> https://spectrum.ieee.org/a-big-hydro-project-in-big-sky-cou... ], in which water is pumped between reservoirs at different elevations—lasts for decades and can store thousands of megawatts for days. > Media reports show renderings of domes but give widely varying storage capacities [--> https://www.bloominglobal.com/media/detail/worlds-largest-co... ]—…

> big yikes for something coming out of the Institute of Electrical and Electronics Engineers. Besides the unit flub, there's an unpleasant smell of sales flyer to the whole piece. Hard data spread all over, but couldn't find efficiency figures. Casual smears such as "even the best new grid-scale storage systems on the market—mainly lithium-ion batteries—provide only about 4 to 8 hours of storage" (huh, what, why?).…

> provide only about 4 to 8 hours of storage" (huh, what, why?)

Because the most efficient way to make money with a lithium ion battery (or rather the marginal opportunity after the higher return ones like putting it in a car are taken) is to charge it in the few hours of when electricity is cheapest and discharge it when it is most expensive, every single day, and those windows generally aren't more than 8 hours long...

Once the early opportunities are taken lower value ones will be where you store more energy and charge and discharge at a lower margin or less frequently will be, but we aren't there yet.

Advertising that your new technology doesn't do this is taking a drawback (it requires a huge amount of scale in one place to be cost competitive) and pretending it's an advantage. The actual advantage, if there is one, is just that at sufficient scale it's cheaper (a claim I'm not willing to argue either way).

Re: CO2 batteries that store grid energy take off globally

#153

Post by selcuka »

svpk wrote: post #143
Waterluvian wrote: post #117

Earlier quoted context omitted.

If 1 watt is 1 joule per second then, honestly, what are we doing with watt-hours? Why can’t battery capacity be described in joules? And then charge and discharge being a function of voltage and current, could be represented in joules per unit time. Instead its watt-hours for capacity, watts for flow rate. Watt-hours… that’s joules / seconds * hours? This is cursed.

I believe it's just a matter of intuitively useful units. There's simply too many seconds in a day for people to have an immediate grasp on the quantity. If you're using a space heater or thinking about how much power your fridge uses kilowatt hours is an easy unit to intuit. If you know you have a battery backup with 5 kilowatt hours of capacity and your fridge averages 500 watts then you've got 10 hours. If you con…

True. Otherwise we would be using square meters for measuring gas mileage instead of miles-per-gallon (or litres-per-km) [1].

[1] https://what-if.xkcd.com/11/

Re: CO2 batteries that store grid energy take off globally

#154

Post by gpm »

hunter2_ wrote: post #151
SigmundA wrote: post #142

Earlier quoted context omitted.

Newton meter as a unit of energy is not the same as the newton meter unit of force for torque. The energy unit meter is distance moved, while the force unit meter is the length of the moment arm. This is confusing even though valid, so the energy unit version is rarely used. You can exert newton meters of force while using no energy, say by standing on a lug nut wrench allowing gravity to exert the force indefinitely…

Ah! I guess that explains the "f" for "force" in the imperial abbreviation "ft-lbf", to distinguish it from work. I wonder if there's ever been an analogous variant for metric such as "Nmf"...

Hmm, I thought lbf was to distinguish the force unit from the mass unit (1 lbf = G * 1lb mass)

Re: CO2 batteries that store grid energy take off globally

#155

Post by thradgt »

cornstalks wrote: post #150
mannyv wrote: post #137

I have two solar panels that can generate around 960w/hr. Both panels cost around $400 ($200x2). Cheap. Storing that energy is quite expensive. an Anker Solix 3800, which is around 3.8kwh, costs $2400 USD. To store 10kwh would cost $7200 USD (which gets us more than 10kwh). If that cost asymmetry can come down then it becomes feasible to use solar power to provide cheap/local electricity in poor countries at a house…

There are way cheaper options than the Anker Solix 3800. Here are some options, in no particular order: - $3,300: 10 kWh with 2x EG4 WallMount Indoor 100Ah. - $3,110: 14 kWh with 1x WallMount Indoor 280Ah. - $2,690: 10 kWh with 1x Deye RW F10.2 B - Will Prowse's YouTube channel has reviewed several battery builds that are >10 kWh and near $2,000, but they're DIY assembly.

Batteryhookup has batteries for $40/kWh :) just put together a off grid setup for a friend and 8kwh cost $400 in parts!

Re: CO2 batteries that store grid energy take off globally

#156

Post by lostlogin »

selcuka wrote: post #153
svpk wrote: post #143

Earlier quoted context omitted.

I believe it's just a matter of intuitively useful units. There's simply too many seconds in a day for people to have an immediate grasp on the quantity. If you're using a space heater or thinking about how much power your fridge uses kilowatt hours is an easy unit to intuit. If you know you have a battery backup with 5 kilowatt hours of capacity and your fridge averages 500 watts then you've got 10 hours. If you con…

True. Otherwise we would be using square meters for measuring gas mileage instead of miles-per-gallon (or litres-per-km) [1]. [1] https://what-if.xkcd.com/11/

> miles-per-gallon (or litres-per-km) [1].

The UK is metric except for distance and beer.

So the disgusting ‘miles-per-litre’ is presumably needed too.

Re: CO2 batteries that store grid energy take off globally

#157

Post by jojobas »

epgui wrote: post #29
creativeSlumber wrote: post #27

Earlier quoted context omitted.

Comparing it to X flights maybe correct from a greenhouse emissions standpoint, but extremely misleading from a safety perspective. A jet emits that co2 spread over tens of thousands of miles. The problem here is it all pooled in one location. Also that statement of 70 meters seem very off, looking at the size of the building. What leads to suffocation is the inability to remove co2 from your body rather than lack of…

It's a gas in an open space, it diffuses very quickly.

It also deflates pretty slowly. I'd guess any breeze would remove the hazard altogether.

Re: CO2 batteries that store grid energy take off globally

#158

Post by idiotsecant »

We desperately need mass energy storage. Everyone gets excited about renewable generation, but it is counterproductive without investing 5x-10x what we spend on generation in improved transmission and storage. It would be better to build 1/10th the amount of solar we do and pair it with appropriate energy storage than it is to just build solar panels. This is a crisis that almost nobody seems to talk about but is blindingly obvious when you look at socal energy price maps. The physics simply doesn't work without storage!!

Re: CO2 batteries that store grid energy take off globally

#159

Post by acyou »

Waterluvian wrote: post #117
nayuki wrote: post #109

> The tried-and-true grid-scale storage option—pumped hydro [--> https://spectrum.ieee.org/a-big-hydro-project-in-big-sky-cou... ], in which water is pumped between reservoirs at different elevations—lasts for decades and can store thousands of megawatts for days. > Media reports show renderings of domes but give widely varying storage capacities [--> https://www.bloominglobal.com/media/detail/worlds-largest-co... ]—…

If 1 watt is 1 joule per second then, honestly, what are we doing with watt-hours? Why can’t battery capacity be described in joules? And then charge and discharge being a function of voltage and current, could be represented in joules per unit time. Instead its watt-hours for capacity, watts for flow rate. Watt-hours… that’s joules / seconds * hours? This is cursed.

Plenty of people use Joules or rather kilojoules or megajoules or even gigajoules for various purposes.

Watt hours is saying, how long will my personal battery pack last me that powers my 60 W laptop? Which is also fine in that context.

Re: CO2 batteries that store grid energy take off globally

#160

Post by hunter2_ »

gpm wrote: post #154
hunter2_ wrote: post #151

Earlier quoted context omitted.

Ah! I guess that explains the "f" for "force" in the imperial abbreviation "ft-lbf", to distinguish it from work. I wonder if there's ever been an analogous variant for metric such as "Nmf"...

Hmm, I thought lbf was to distinguish the force unit from the mass unit (1 lbf = G * 1lb mass)

It seems the common thread is that the f means to introduce G, but not exactly. In my own research, the AI summaries are about as sloppy as I've ever seen, due to the vague and often regional differences (with the difference between ft-lb and lb-ft sometimes being described as relevant, as well).
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