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0 pointsRetric2y ago0 comments

The numbers really aren’t that insane when you consider how quickly battery production has been ramping up. Nearly 100% of passenger cars going EV fairly quickly isn’t crazy looking at adoption curves. It’s likely those slow down soon, but continuing to build factories just as fast for grid storage is perfectly reasonable.

There’s over 280 million cars in the US, assuming on average that’s ~75kWh each we’re looking at ~21 tWh worth of battery storage. Meanwhile the average daily electricity use in the US is currently only 11 tWh. Of course that increases in a 100% EV world but EV’s are generally quite flexible demand.

PS: Solar power plants are often built to store ~50% of their daily output in batteries. It’s currently economically viable because that’s released at peak demand and thus peak prices, but with how quickly battery prices have been falling they will soon be viable even for normal nighttime prices.

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rtkwe2y ago· 1 in thread

Back feeding and metering all that power isn't exactly simple and it's also a big economic cost to just shove onto people in the form of increased battery wear and effectively reduced range since the most common trips begin early in the morning before renewables like solar come back online to produce the excess needed to recharge all the cars you've borrowed power from over night. Because of that cost that kind of distributed battery power is going to come out quite expensive unless you're just vastly underpaying for the depreciation of the battery like Uber does for it's drivers' cars wear and tear.

Another big thing is your 21 TWh number has huge flaws. That's fully draining everyone's batteries to provide the power and no one is going to accept that we want the cars because we need to go places. Next we're decades away from even getting close to full EV penetration. Even if we stop selling new ICE vehicles they're durable goods that people hold on to for a long time. It's the kind of 'Company/technology X takes over everything' assumption that so vastly inflates the valuations of tech companies all over the sector.

RetricOP2y ago

It was simply an order of magnitude comparison for manufacturing capacity. Slowing EV adoption at say 50% penetration would be beneficial for the grid as that excess capacity in mining and manufacturing could be used for grid batteries.

I doubt the the cheapest grid has anywhere close to 21 tWh as having more generation is more useful. Hydro is extremely flexible and reliable can fill in for a modest and predictable multi day shortfall. On the other hand if a power plant is down then batteries get extremely expensive.

That said, the cost of batteries isn’t simply a function of total capacity as unused capacity extends battery lifespan. The actual grid will take this into account which then impacts spot prices etc. Nobody operating grid scale batteries is going to 0% for wholesale prices of 5c/kWh but you bet your ass they’re going to 0% for 1$/kWh.

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rtkwe2y ago· 1 in thread

RetricOP2y ago

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