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Comment by don_esteban | Hacker News Reader

60% (20%->80%) of 85kw battery = 51kW in 10min = 305kW charging power.

An electric charging station with 8 charging booths (=~ gas pump) on a highway: 2.5MW.

A bit of work to prepare the grid...

I'm not into the latest EV power transfer technology, but that's more than the rating of a neighborhood distribution transformer per car. That's an insane amount of power to have someone casually handling. Would there be additional rules like in a gas station when charging up? Those cables and connectors must be massive as well.

A lot (most?) new EVs support 200+kW charging and there are quite a lot of 400kW chargers around already.

Plenty of stations handle this already. Power distribution in industrial areas is already quite high. Also, the cables and connectors are a lot smaller than you think… most 250kW+ stations use liquid cooled cables so they’re relatively flexible.

Charging stations in remote locations use batteries to smooth the load so that they don't need a 2.5MW connection.

With a 95% efficient grid, and a 85% efficient battery, and a 80% efficient car you'd get an overall efficiency of ~65%. Still better than an ICE, I guess, and you can use local solar energy.

It's probably not even too expensive.

The batteries should be much more efficient than 85% since they wouldn't use an inverter.

Vehicle to load type solutions will make the grid impact of EVs negligible. In fact over time it will help stabilize the grid and add storage for peak solar/wind generation. Imagine having most vehicles plugged in at an office building during the day for example, in a power outage the office building would be able to run off of the vehicles. Nissan in fact has such a setup[1]

1. https://www.nissan-global.com/EN/STORIES/RELEASES/nissan-wor...

12 x 350kW charging stations being installed at the moment, so presumably that work to prepare the grid has already been done.

I believe that we CAN make EVs work with the grid in a way that's good for both, but I increasingly worry about political fights about EVs and grid stability.

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