Yeah, so, the first thing to know about that is ICE is ludicrously inefficient. Spinning all that metal at variable speed with tiny explosions is, unsurprisingly, not the best way to turn high density fuels into energy. The thing ICE had on its side is the energy density, on other metrics it's a bad deal (hence why free charging for EVs is affordable)

So if you have 400MW of ICE cars you don't need 400MW of electricity to replace that, something more like 80-100MW is more like it IIRC. The infrastructure build cost isn't zero, but it's much less than this 150% metric suggests.