• @Resonosity
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    5 months ago

    EE here. Chargers put out power in units of kW, while batteries store energy in units of kWh or MJ or what have you. Otherwise, you’re absolutely correct.

    Typically Distributed Generation (DG) scale solar PV and battery storage sites are sized anywhere from 1 to 10 MW.

    At 1 MW, you could run (1) charger at a speed of 1 MW, or (2) at 500 kW, etc. Usually need just (1) transformer for that size installation too.

    At 10 MW, you can run each charger at 1 MW or so, but you’re also talking about probably (4-10) transformers @ $250k USD a pop. Installation prices go up the more you demand in power transfer.

    Then you need to consider that most DG projects need to pay for the upgrades to their downstream grid architecture, meaning reconducting or upsizing cable, breakers, switches, transformers, reactors, sensors, relays, etc.

    Not saying it’s impossible. You could co-locate and DC-couple solar PV or Wind parks next to charging points to get around some of the grid upgrades, but most people live in areas that require homes and grocery stores and other buildings than flat land meant for solar PV or Wind.

    When it comes down to it, it’s so much easier to just trickle charge your EV at night via arbitrage and when you’re sleeping so all of this infrastructure doesn’t have to been upgraded - and I’d argue upgraded needlessly because we need to save that copper and iron and materials for upgrades to the parts of the grid meant to interconnect renewables.

    But there is no silver bullet to these things so we’ll likely see more, larger chargers come through unless regulators stop it from happening.