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Comment by monkeynotes | Hacker News Reader

I'm still unsure how a country could switch from gas to EV. Could a city keep up with the power demands when everyone plugs in their EVs at night? I am assuming we'd have to build more power generation capacity, and what is the source? How do you transmit all the high capacity power to quick charge stations on the highway when you have 200+ cars an hour needing to quick charge?

It all sounds like an enormous infrastructure upgrade. Europe is already committing to EV and outlawing gas engines in the next 10-20 years so it will be interesting to learn how they plan to accommodate the huge electricity generation and transmission demands that go with that.

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Most nations still have peak demand infrastructure setup for daytime industrial power demand, most of which already requires high capacity delivery. That demand hugely drops off in the evenings as factories shut down for the day and workers return home.

Most new EV power demand happens in the evenings, "filling in the bathtub" (because the average demand graph looks like a bathtub) that the industrial demand curve leaves behind. The difference between industrial (daytime/peak) and consumer (evening/off-peak) demands is a big enough bathtub that estimates are that it would be a while before EV cars get even close to filling in the bathtub.

One estimate I saw was that if every car on the road switched to an EV car tomorrow and charged only at off-peak times, it would almost fill the bathtub, and thus require no actual generation increase.

That doesn't deal with the infrastructure chicken-and-egg issues of street-level and parking structure access to car charging, of course.

Street level charging and parking are only important if you think car ownership and not mobility services will be the way electric gains the bulk of its market share.

Even "mobility services" would need parking structures with chargers, and comprehensive street level charging would also be useful to them for just-in-time logistics.

Personally, I think that if there is a transition coming from car ownership to "mobility services", it's going to be a slow one, especially in America where personal vehicle ownership is seen so much as a rite of passage and requisite "freedom".

Ironically it is going to be easiest for places with the cleanest power (hydro, nuclear, geothermal, wind) because clean power tends to be non-burstable while fossil fuels are.

So in places like France or Ontario what will happen is that the cars will automatically charge when rates are low (at night) and may even help the grid by acting as remote batteries. For example, you could keep your car at a 70% minimum charge as a configuration then allow the power grid to pull from you as needed. This would passively reduce your overall power bill as you're selling at peak demand and buying at peak supply.

while also depleting the battery's lifespan.

sounds like a perfect opportunity to get careless car owners to destroy their own property for a company's revenue.

especially hilarious if the car owner doesn't use an expensive UPS between the grid and the car. I'm sure the next lightning storm isn't too far off - and some of the plugged in cars won't survive it.

I'm not against EV though. There'll however be a lot of growing pains as they take over the cities. (though thats still far off)

This can be modelled with net present value accounting. If, at scale, it is financially worth it for Tesla to manufacture giant batteries for the electric grid then it will also be financially viable for the electric grid to use spare battery capacity.

Distributed grid battery storage via EVs is an interesting idea and I'd think a 70% charge would be possible for commuters. However, when everyone gets home plugging in to get back what they supplied out during the day I am curious to see how the network would deal with that load. Imaging Toronto with 25% of households consuming an additional 20kwh a day, that's a considerable change. Apartments in Toronto probably use about 18-25kwh a day on average, you'd essentially be doubling that for a quarter of the city. I'd love to know if that's manageable / what industry experts are thinking. (My numbers are all backed by very crappy quick internet searches and guestimates)

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