21–30 of 118 posts
The phrase "2 MW of energy" makes no sense based on units. Shouldn't writers (and editors) be required to at least take high school physics or chemistry?
I took those things m, and I’m a successful software engineer and founder with an exit. I can never remember anything but joules for energy. Which I think doesn’t matter? And my RV has amp-hours? No fucking idea.
I admit in the past I've been skeptical about the use of gravity batteries when they involved things like towers and stacking large weights as their energy density is relatively quite low, but this seems like it makes a ton of sense. That is: 1. The shaft is already dug, so no need to build a tower. 2. As the article points out, many/most of these sites are already well-connected to the grid. 3. Also as pointed out i…
You'd think that in an article specifically about energy storage, in the introductory paragraph, they'd get the units right. > The Pyhäsalmi Mine, roughly 450 kilometres north of Helsinki, is Europe’s deepest zinc and copper mine and holds the potential to store up to 2 MW of energy within its 1,400-metre-deep shafts.
It's frustrating, every article just repeats "2MW capacity." Gravitricity hasn't announced this project themselves yet, hopefully when they do they give the actual storage capacity. But I think 2MWh might be correct - in press elsewhere Gravitricity says 500t over 800m produces 1MWh. This is a deeper depth but not that much, and this is very much an experimental project so I think they might be sticking to 500-750t m…
Earlier quoted context omitted.
> The IIASA analysts noted that mines already have the basic infrastructure for such an endeavour, while also being connected to the power grid. “This significantly reduces the cost and facilities for the implementation of Underground Gravity Energy Storage (UGES) plants,” the study noted. Not that your wholly unsupported naysaying isn't compelling.
Connected to the grid yes but usually the interconnect is simply enough for running the mine not enough to cover many megawatts of storage capability. The battery storage companies have found that there is an abundance of fields and brownfield sites close to existing substations to place their batteries where the cost of connecting to the grid is minimal.
Mines can use a LOT of electricity. I found a presentation from EPRI[1] talks about varoius electric vehicles and machines used in underground mining. One slide references a "mining system" that alone draws 5-10Mw. Even if you take that as "the whole mine uses 5-10MW", it means that it's grid connected well enough to handle Mw of storage.
[1] EPRI is a respected R&D non-profit in the electricty sector. The slides: http://mydocs.epri.com/docs/publicmeetingmaterials/1203/jkn2... the slide I reference is #14.
- 2 MW of energy
MW is a unit of power not energy, maybe they mean 2 MWh, but if that's the case, it is a joke. That's like 30 Teslas cars, or half of a Tesla Megapack, which is a shipping container sized battery. 2 MW of power is not that big either, that's about what you get from a typical wind turbine.
- 70TWh of energy
At least, we have a proper unit, but I wish they tell us a bit more about how they got a number 7 orders of magnitude larger than the previous one.
- A study last year by the International Institute for Applied Systems Analysis (IIASA)
What study? Source please
I wonder if that is part of the impetus - make cleanup/decommissioning happen in distant future dollars helps the balance sheet today.
https://www.marketscreener.com/quote/stock/ABB-LTD-9365000/n...
I admit in the past I've been skeptical about the use of gravity batteries when they involved things like towers and stacking large weights as their energy density is relatively quite low, but this seems like it makes a ton of sense. That is: 1. The shaft is already dug, so no need to build a tower. 2. As the article points out, many/most of these sites are already well-connected to the grid. 3. Also as pointed out i…
A gravity battery doesn't need a well or a tower. The slope of a hill will do. More or less put railroad tracks up the slope, and have the "car" winched up and down. Just like the ratcheting trolleys that go up and down hills.
Isn't there a better article? - 2 MW of energy MW is a unit of power not energy, maybe they mean 2 MWh, but if that's the case, it is a joke. That's like 30 Teslas cars, or half of a Tesla Megapack, which is a shipping container sized battery. 2 MW of power is not that big either, that's about what you get from a typical wind turbine. - 70TWh of energy At least, we have a proper unit, but I wish they tell us a bit mo…
https://www.marketscreener.com/quote/stock/ABB-LTD-9365000/n...
This must be orders of magnitude more expensive than pumped hydro and I would expect more expensive than lithium batteries. And unless the mine is close to an existing high voltage substation then there will be significant costs hooking it up to the grid. The pilot will be a 2MW generator but you can fit a 2MW inverter and a 2MWh battery into a single shipping container so the scale is really minimal.
> The IIASA analysts noted that mines already have the basic infrastructure for such an endeavour, while also being connected to the power grid. “This significantly reduces the cost and facilities for the implementation of Underground Gravity Energy Storage (UGES) plants,” the study noted. Not that your wholly unsupported naysaying isn't compelling.
Cliff's Notes: any currently-considered form of gravity storage that isn't pumped hydro is orders of magnitude more expensive and more stupid than a Tesla Megapack.
Michael Barnard's abrasive tone aside, is he wrong?
Earlier quoted context omitted.
> The IIASA analysts noted that mines already have the basic infrastructure for such an endeavour, while also being connected to the power grid. “This significantly reduces the cost and facilities for the implementation of Underground Gravity Energy Storage (UGES) plants,” the study noted. Not that your wholly unsupported naysaying isn't compelling.
Allow me to support the completely unsupported naysaying: https://cleantechnica.com/2024/01/16/gravity-storage-101-or-... Cliff's Notes: any currently-considered form of gravity storage that isn't pumped hydro is orders of magnitude more expensive and more stupid than a Tesla Megapack. Michael Barnard's abrasive tone aside, is he wrong?