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by sir_bearington 1927 days ago
> That’s ~2.7 orders of magnitude time larger than the cited current installed storage, which isn’t even remotely 6+ orders of magnitude.

But almost all (~95%) of the installed grid storage capacity is in hydroelectric storage. The above commenter is posting in terms of battery storage in the 100MWh range. We would indeed need 6 orders of magnitude larger than this even to just have 1 day's worth of storage. Hundred megawatt hours vs a dozen Terawatt hours.

Also, the amount of storage could be substantially more than a day in a predominantly wind + solar grid. Part of variability is mostly daily, with the sun going up and down. But both solar and wind are also affected by weather. That requires much more substantial amounts of storage to get the grid through consistent days of reduced production. Estimates to provide a 100% carbon-free grid with renewables go as high as 3 weeks [1]

1 comments

I'm assuming that your citation is meant to refer to this paper: https://pubs.rsc.org/en/content/articlelanding/2018/EE/C7EE0...

It says that 3 weeks of power storage would be required in total absence of a serious overhaul in transmission capabilities. I had assumed that was a clear, if unspoken, assumption when I was discussion continent scale entities.

Also, the poster you originally responded to was discussing the literal dozens of installations that singlehandedly meet the 100 MWh mark. HN guidelines require that I assume this was a simple failure of reading comprehension.

Even a much more modest goal of provisioning a single day of storage would entail 11.5TWh of storage. Dozens of 100 MWh facilities is still in the single digit GWh range. That's six orders of magnitude. And this isn't even taking into account handling heating, industrial use, and all the other forms of tapping into fossil fuel energy besides electricity.
10TWh / 1 GWh = 10^4

Where on earth is six orders of magnitude coming from? You’re off by a factor of a hundred.

Global daily electricity consumption is 60TWh per day. And that's only Electricity consumption. Total energy consumption is more than 100TWh per day. The duration of storage to fulfill 100% of this demand with renewables varies depending on energy mix, long distance transmission, and more but is usually in the range of at least one day's worth of storage.

The point is that dozens of 100MWh stations is basically nothing. You'd need millions of these sites to make renewables a feasible primary source of energy. Our current technology is not sufficient to make energy storage available to make grid storage viable.

Yes a dozen 100GWh facilities is 1.2 GWh, and that's an order of magnitude less in difference, I don't doubt your ability to multiple by factors of ten.