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Comment by pwarner | Hacker News Reader

Between 4 PM and 9 PM. Everyone charges at night anyways I think? Even without an elictricity shortage, it's expensive between 4 and 9..

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Also excludes mention of solar installations and possibility of vehicles supporting V2L to support the grid in emergency.

Much of my take is, if you want an EV then you should be ready for solar as well. EVs and solar are a great combination that can support the grid in emergency.

>> if you want an EV then you should be ready for solar as well

45% of Californians are renters. They don't control whether or not solar is installed.

Given your assertion and that fact, is making it illegal to purchase a car with an internal combustion engine a good idea or a bad one?

OP’s assertion is unnecessary. Whether you have solar or not, for most people it won’t be hard to avoid charging between 4-9pm.

Many things are possible between now and 2035, and a mandate/subsidy for landlords to install chargers is one of those possibilities.

> OP’s assertion is unnecessary.

That could be said about any opinion shared. Regardless of your opinion of my assertions, energy source and costs are a necessary factor in the economics of operating BEVs. If you can't source cost effective solar energy, it may not make economic sense (long term, as costs rise) to own a BEV for renters. Per mandates/subsidy, the subsidy already exists (may need adjustments), a mandate may be necessary.

You seemed to be making the argument that without solar owning an EV may not make economic sense for the EV owner.

I don't think that's related to the outcomes of the transition to an EV mandate for new sales, which is what the respondent was asking about. Sure, it's nice to have your own solar panels, but it's not a requirement for EV ownership, and I was pointing out that your assertion, whether true or false, was unnecessary for the EV transition to be a "good idea" in the parent poster's words.

That said, regardless of how you power your vehicle, even in some of the most expensive power markets, overnight charging is cheaper than gas, both economically and environmentally.

I would assume that the load through EV charging starts increasingly rapidly after work, which is precisely in that time period. But it's also not like they're singling out EV's. They mention a number of measures they'd like people to take to reduce electricity consumption.

But most EV's have settings to do delayed charging. In mine I can set it to either start charging after XX:XX or I can set it to be ready at a certain time, fx 7:00 in the morning.

Some chargers also supports these settings.

In the deep past, given how many VCR clocks remained at 12:00 because their owners never set the clock, how many EV owners to you think are going to bother explicitly setting a "charge time" in their EV?

Unless it ships from the factory with "charge only during hours X to Y" preset and turned on, the vast majority are not going to get set for a delayed charge time, and will simply charge whenever plugged in. And their owners are likely to "plug them in" at the end of every trip so they are sure to be "topped up" for their next trip.

My utility gives me half-rate electricity if I charge after midnight ($0.11/kwh vs $0.23/kwh) - people will line up and wait for 20 minutes or drive across town to buy gas that's $0.03/gallon cheaper, I think they'll figure out how to set the 'delay charging' option on their car if it gives them the equivalent of half-off gas prices.

> Unless it ships from the factory with "charge only during hours X to Y" preset and turned on,

Hey look, you answered your own question!

It's much cheaper for our town to charge in off peak hours. I'd be burning money if I charged my car after work, only for it to just be plugged in all night not charging when it's cheap.

I wouldn’t charge at night in a house with old wiring. 11 kW is a lot of power. Fire risk might be really high.

Dont 11 kW assume a charger installed by an electrician? Then they would have pulled cable that can handle 11 kW to make a installation.

(or maybe I am totally wrong, I am not from the US, in my location I cant install a 11 kW charger by myself legally).

> or maybe I am totally wrong

For the US, no you are not "totally wrong". The majority of 11kW EV charge ports will have been installed by an electrician and also inspected by the local govt. electrical inspector because the vast majority of people simply do not try do to this work themselves.

However, in many locations in the US, homeowners are allowed to do their own electrical installs, provided they pull a permit and have the required inspection performed. Those should also meet code, as otherwise the inspector should have failed the install.

Which only leaves those who will do the install without pulling a permit and having an inspection. What percentage of the total those would be I do not know, but given that few do their own electrical work anyway, it is probably a very small percentage of the total. And a sub-set of those would do the install properly to code anyway, even without the permit and inspection.

Presumably if you install an 11kW (50A circuit) 240V EVSE, you're adding a new breaker to a service panel of at least 150A and going directly to the EVSE with a new cable. The risk of electrical fire would be minimal.

Why would you charge with 11kW over night?

I do that because its cheaper to charge over night. I have a 11 kW charger installed on my house.

If the car is parked for 8h or so at home you can probably charge it with 2kW and still have a full battery in the morning.

Math does not work here: 8h x 2kW = 16kWh. Tesla has 60 or 100 kWh batteries. It only works if you take only short trips (like commuting to work) and never go below 70% of charge.

It works perfectly fine if you plug in every night in your garage and don't drive more than 100km a day. If your commute is longer you might need 3 or 4kW, but probably not 11kW.

And if you take a longer weekend trip you'll need the whole next week to catch-up on charging. 11kW seems like necessity - it allows you to charge 0-100% overnight. No advance planning, no compromises required.

Also, I'm curious: in my country it is pretty common to have 11.5 kWh installation at home (it was even before advent of electric cars), is the US somehow limited in that regard?

American mains are single (split) phase 240v, your country's are likely 3 phase 240v. Your appliances are likely hooked to 3 phases simultaneously with a 20A breaker so they can get 12kW, American 20A hookup is only good for 4 kW (240x20x0.85 because you cannot draw more than 85% of max power continuously by code).

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