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Gravity batteries try to beat chemical ones with winches, weights, mine shafts

sciencemag.org

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Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#141

Post by ianai »

martinald wrote: post #127
audunw wrote: post #90

Earlier quoted context omitted.

It's a common misconception that energy storage needs to handle all the power needs of an area for a significant time. The most immediate need for energy storage is frequency regulation, and short hours-long dips in power output. If we can solve that we can scale renewables very far. For days-long dips in power output, it's probably better to keep some gas power plants on stand-by. I think many areas of the world has…

Not true in northern European countries. The problem isn't day to day regulation, it's the massive demand in cold snaps in winter (when there is very little wind generation - cold weather tends to have little wind). You're talking balancing 20-30GW of additional demand with little solar/wind generation for weeks/months - probably at least 1TWh of storage required for the UK alone. Keep in mind this will only get wors…

I’d just build the generation out to that maximal use case. During the off peak times power a desalination, hydrogen, or other energy intensive plant.

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#142

Post by patall »

runeks wrote: post #76

Here's an idea: what if -- instead of digging a deep hole into the ground -- we use the tower of a wind turbine as the vertical space in which the weight is raised/lowered? A wind turbine is already equipped with a generator, so it'd be a matter of building some sort of "switch" which would make it either: (a) generate electricity using the turbine, as per usual; (b) raise the weight using the turbine, thus not produ…

Funny how people tell you that that this does not make any sense at all, but here it is: http://www.naturspeicher.de/en/naturstromspeicher.php

(Yes, I am aware that it is not storing the water at the top :)

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#143

Post by guerby »

tralarpa wrote: post #98
guerby wrote: post #21

"But Schmidt’s calculation of the lifetime cost per megawatt-hour for lithium-ion batteries, $367, is more than twice as much" This is ridiculous. I'm charging right now my EV from a 14 kWh 16S LFP pack which costed me $1400 tax paid and delivered. LFP properly managed will do minimum 3000 cycles, so that's 42 MWh for $1400 which gives $34 per MWh out of the battery. Note: 5kW 48V inverter cost $500.

> 14 kWh 16S LFP pack which costed me $1400 Wow, that's amazing. But why are home battery systems still so expensive? I see system prices in the range of $700 to $1200 per kWh. Even on aliexpress, it's minimum $550/kWh. Is the inverter so expensive?

Niche market so high markup to pay for the maker margin and the seller margin.

I found the vendor by following:

https://diysolarforum.com/

https://www.youtube.com/channel/UCoj6RxIAQq8kmJme-5dnN0Q

DIY Solar Power with Will Prowse

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#144

Post by Ekaros »

raverbashing wrote: post #88
robertlagrant wrote: post #3

Gravity based battery, stuffed full of lithium ion batteries?

Maybe the solution is using very dense material. Like nuclear power plant waste.

Or then we could use lot more of this pretty cheap, pretty available, pretty easy to handle stuff that we have mature technology and understanding for. Namely water. Only thing is that need nice reservoirs on top and bottom. The shaft it self can even be narrower and less sturdy...

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#145

Post by hutzlibu »

dopidopHN wrote: post #138
hutzlibu wrote: post #79

Earlier quoted context omitted.

"Also, we already have gravity-based systems, only nature does all the work of raising the payload for us in gaseous form, and we let it fall in liquid forms. But it takes so much dam place" We actually also do have self created gravity-based systems, where we also do the work by ourself, to have a energy storage on demand: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... They work reliable and with bi…

Side note on what is currently existing with gravity. The suiss folks are gaming the west European energy market this way. When the French produce too much nuclear energy, the German have leftover and stop buying it 100%w Price go down. Swiss buy it cheap and pump water in their dam system with it. Inevitably, the french grid align and produce a bit less. Price goes up slightly. That when the suiss comes out, release…

Maybe I do not understand it fully (ne pas parle de francais), but where do they game the system?

You buy cheap when you have storage and sell expensive when demand goes up. Pretty much how the market should work?

This way there is incentive to balance it out (by creating storage) - and in this case stabilize the grid.

When the grid would become more flexible, so even homeowners can do this with their solar panels and big batteries - then this should be net gain for everyone, no?

Unless gaming it, with big money, destabilises it. So some safeguards probably should remain.

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#146

Post by kstenerud »

audunw wrote: post #90
rakoo wrote: post #48

As usual everyone is fixated on price when the real hurdle will be scale. If we're going to replace our existing fossil fuel plants we need at least as much capacity. A quick grep in the article tells me these guys have a plan for a 4MW plant that involves a 1km shaft. That's the same order of magnitude as a single wind turbine, which is already one of the worst ratio of power output per quantity of resource and land…

It's a common misconception that energy storage needs to handle all the power needs of an area for a significant time. The most immediate need for energy storage is frequency regulation, and short hours-long dips in power output. If we can solve that we can scale renewables very far. For days-long dips in power output, it's probably better to keep some gas power plants on stand-by. I think many areas of the world has…

Actually, almost none of our trash is recyclable (despite what you've heard). Plastic is particularly bad, and it's only now, with China banning import of "recyclable" materials, that we're finally seeing just how much of a farce it is.

Burying it is a form of CO2 sequestration. Burning it just releases it into the atmosphere.

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#147

Post by ms4720 »

cogman10 wrote: post #136
martinald wrote: post #127

Earlier quoted context omitted.

Not true in northern European countries. The problem isn't day to day regulation, it's the massive demand in cold snaps in winter (when there is very little wind generation - cold weather tends to have little wind). You're talking balancing 20-30GW of additional demand with little solar/wind generation for weeks/months - probably at least 1TWh of storage required for the UK alone. Keep in mind this will only get wors…

This seems like a "running before we can walk" statement. Until we can handle day to day problems, it seems weird to worry about edge cases. I imagine as we transition to renewables and storage we will still have fossil fuel peeker plants to handle these sorts of snaps. It won't be until our power storage is far more beefed up that we'll shut those down, and that will take years.

A cold snap like that can happen every 3-5 years, think really cold February. If you don't have the capacity to handle it people will die and lots of things will break. It is not an edgcase

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#148

Post by alexchamberlain »

PeterisP wrote: post #75
alexchamberlain wrote: post #15

Earlier quoted context omitted.

Their marketing has the LCOS of those 2 solutions the other way around - $171 for Gravity, $367 for Litium Ion batteries. See https://gravitricity.com/technology/

Too bad they don't seem to provide the actual report anywhere (and neither does ICL), they just quote a single chart from that without any details. This feels fishy to me - I'd want to look into the cost basis they used, as a key problem with comparisons against batteries is that the battery cost has changed so much over the recent years (halving every 5 years or so), and many studies quote their battery price calcul…

Whilst I agree the components of a mechanical battery are probably going to stay stable, I think Gravitricity have an opportunity to commoditise the design and install near sporadic renewables like wind.

Bias: I participated in their crowdfunding campaign.

Re: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

#149

Post by yunohn »

lai-yin wrote: post #120
throwaway189262 wrote: post #106

Earlier quoted context omitted.

Construction material is a meaningless metric. If you compare coal or gas plants you need to consider the materials they consume and infrastructure needed for fuel transport. This is a big number, many times the material used for the plant itself. The only meaningful comparison is material used vs solar. Once these things are built they use near zero resources. For everything else you have to keep mining shitloads of…

Sorry but you don't get to discount wind turbines' ecological damage just because no more mining is involved post-construction.

Please link to a source/calculation where a wind turbine uses more resources than a coal plant to build. I mean, you can even do napkin math and see that there’s no way multiple buildings and vast mining infrastructure take less material than a turbine farm.
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