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CO2 batteries that store grid energy take off globally

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Re: CO2 batteries that store grid energy take off globally

#211

Post by throwawaymobule »

skissane wrote: post #164
lostlogin wrote: post #156

Earlier quoted context omitted.

> 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.

Also the UK gallon is different from the US gallon. And the same applies to all the other non-metric fluid measurements such as pints and fluid ounces. Historically the UK gallon was used throughout the former British Empire (Australia, Canada, India, Ireland, Malaysia, New Zealand, South Africa, etc). By contrast, almost nobody ever officially used the US gallon except for the US (and a small handful of highly US-in…

Each standardised on a different gallon. Prior to that, gallons depended on that you were measuring.

One, a beer gallon, the other a wine gallon. The US still also has 'dry gallons' for things like pints of blueberries.

Re: CO2 batteries that store grid energy take off globally

#212

Post by zhivota »

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…

Here's a quote I got for a solar install in the Philippines this week:

51.2v 314ah cells (15kwh battery) 16x 580-590w solar panel

Installed for 310k PHP = $5,275

I've also specced out 15-16kwh batteries using the Yxiang design for around the price of your Solix. The problem in the US is regulatory and a particularly predatory tradesman market at the moment.

Re: CO2 batteries that store grid energy take off globally

#213

Post by tor825gl »

catlikesshrimp wrote: post #179
eru wrote: post #173

Earlier quoted context omitted.

Well, if you want to be pedantic, it's litres-of-fuel per km-driven. That doesn't cancel as nicely, if you don't drop the annotations. Arguably, we should probably use kg-of-fuel (or mol) instead of litres-of-fuel anyway.

"litres-of-fuel per km-driven" (Volume/Distance) is still fully reductible to an area: litres is still a volume (1 cubic decimeter) and km is still a distance (1x10⁴ dm) Maybe you meant that the other way around? Distance/Volume (as in Miles/gallon) is an Area⁻¹ (Distance⁻²), which is more difficult to imagine in space. Now, Kg is a measure of mass (or weight, depending on who you are asking), which throws density in…

If you car was fueled by a fixed pipe which it travelled along, consuming all the fuel in the sections of the pipe that it moved past but no more, what would the cross section of the pipe be?

Re: CO2 batteries that store grid energy take off globally

#214

Post by tor825gl »

SyzygyRhythm wrote: post #183
ekr wrote: post #176

Earlier quoted context omitted.

What people care about when talking about EVs and consumption is generally how much distance they can cover. If you take away the distance factor and just report power, it becomes meaningless/almost useless.

Many people think of driving in time rather than distance. I'd say it's actually more common to say a city is 3 hours away rather than 200 miles. What makes kW less useful is really just that most EVs don't advertise their capacity very prominently. But if you knew you had an 80 kWh battery and the car uses 20 kW at freeway speeds, then it's easy to see that it'll drive for 4 hours.

The problem with this is that destinations are a fixed distance away, whereas their time distance is not fixed. In most journeys people want to reach a specific place rather than drive for a given amount of time.

Re: CO2 batteries that store grid energy take off globally

#215

Post by tor825gl »

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…

There are two types of jobs, the ones which require you to know that a day is about 8.5x10^5 seconds, and those which don't.

Re: CO2 batteries that store grid energy take off globally

#216

Post by usrusr »

I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful)

Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from the heat storage aren't too big, but when you have a cooling use case nearby, you can use that low intensity heat to compensate heat storage losses, or even overcompensate. When you consider how much of the power input of a datacenter is typically used for cooling, compressed gas storage could be useful even if there was zero electric recovery (just time-shifting the power consumption for cooling to a time with better energy availability)

Re: CO2 batteries that store grid energy take off globally

#217

Post by 3D30497420 »

nazgul17 wrote: post #202
PunchyHamster wrote: post #192

Earlier quoted context omitted.

If it is barely cheaper than lithium, it's much more expensive than traditional pumped storage. Yeah, it's expensive to build, but then cheap to run for decades. It's nice that we explore alternatives but this just seems like investor bait

AFAIU, pumped storage can only be built in very few locations around the globe.

This is mentioned in the article, that you need very specific topography for water pumped storage. Additionally, it can require a lot of space and be quite expensive and time-consuming to build.

Re: CO2 batteries that store grid energy take off globally

#218

Post by audunw »

PunchyHamster wrote: post #192
Jean-Papoulos wrote: post #178

>The company uses pure, purpose-made CO2 instead of sourcing it from emissions or the air, because those sources come with impurities and moisture that degrade the steel in the machinery. So no environmental advantages. It's supposedly 30% cheaper than lithium-ion, but BYD cars have sodium-based based batteries on the road right now which CATL says will end up being 10-20$/kwh (10x cheaper than current batteries). So…

If it is barely cheaper than lithium, it's much more expensive than traditional pumped storage. Yeah, it's expensive to build, but then cheap to run for decades. It's nice that we explore alternatives but this just seems like investor bait

Pumped hydro is just not a valid comparison. I wish people would understand that already… it’s only good for long term storage in certain key geographical regions. Its use case is very limited.

You don’t want to used pumped hydro for short term storage because the rapid cycling will drive up the maintenance costs. You actually hear about hydro power plants talking about installing batteries to reduce wear.

In these discussions please keep in mind that frequency regulation, short term and long term shortage are different applications with different needs. The costs for pumped hydro are generally reported with their target application in mind. It’s not as applicable to dedicated short term storage and certainly not applicable to frequency regulation.

Re: CO2 batteries that store grid energy take off globally

#219

Post by RobertoG »

ycui1986 wrote: post #147
3eb7988a1663 wrote: post #42

Earlier quoted context omitted.

Maintenance of the system is my biggest question. Lot of mechanical complexity with ensuring your gas containment, compressors, turbines, etc are all up to spec. This also seems like a system where you want to install the biggest capacity containment you can afford at the onset. All of that vs lithium/sodium where you can incrementally install batteries and let it operate without much concern. Maybe some heaters if t…

from the picture, the compressor and generator located inside the dome. the dome is filled with CO2. maintenance people have to carry oxygen tank, or they die.

they just do the maintenance when is empty?

Re: CO2 batteries that store grid energy take off globally

#220

Post by jakewins »

alextingle wrote: post #162
gpm wrote: post #152

Earlier quoted context omitted.

> 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 lon…

It ought to be cheaper at scale. Batteries' cost scales linearly with storage capacity. Cost for a plant like this scales linearly with the storage rate - the compressor and turbine are the expensive part, while the pressure vessels and gas bags are relatively cheap. The bigger you build it, the less it costs per MWh of storage.

> Energy Dome expects its LDES solution to be 30 percent cheaper than lithium-ion.

Grid scale lithium is dropping in cost about 10-20% per year, so with a construction time of 2 years per the article lithium will be cheaper by the time the next plant is completed

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