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Comment by SketchySeaBeast | Hacker News Reader

I have a garage, and I struggle with thinking an electric car would be a dream. It's an old detached garage and doesn't have the electrical infrastructure required to provide fast charging. It seems like it'd be another $10k worth of expenses (I assume something like that for the trenching and installation) on top of the car.

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I'd argue most users don't need fast charging at home. 8 hours of level 1 charging gets you 30-50 miles of range, which is pretty much exactly the average daily commute. You can double that range by charging at work (which can be level 1 too).

For rare longer trips, public fast charging infrastructure is quite convenient.

You probably don't need fast charging for charging overnight. I charge my EV off a standard 120V/15A outlet and that's more than enough to keep the battery topped up.

A level 1 charger will add 3-4 miles of range every hour it's plugged in. Assuming you don't have some wildly long commute, that's easily enough to cover most people's daily driving in 8-10 hours of charging overnight.

Do you need fast charging at home? We just charge our electric car overnight from a normal UK 240V 13A socket in our garage.

240V/13A is significantly more power than the standard outlets in the US (120V/15A), but even here in the US I find a level 1 charger is more than sufficient to cover my daily driving by charging overnight.

That’s twice as much power as a US 120V 15A receptacle

.8*120*15 = 1440w vs 230*13 = 2990w

You can only use 80% of a load on a breaker in the US, AFAIK UK receptacles are fused which allows using 100% of the listed device ampacity instead of 80%. I could be wrong about that last part though.

In the UK there is usually a fuse in the plug, the fuse value varies according to the appliance up to a max of 13A.

I'm in the UK where every home already has 230v power at the consumer unit/breaker panel.

I don't have an EV charger, but I did have a 32A 230v power feed installed to my detached garage, suitable for a 7.4kW EVSE in the future. Parts and labour cost less than $650. It was a day's work for one man; he used armoured cable that doesn't need to be buried very deep, and could cross paved areas just cutting a 2" slit.

This was in a high cost-of-living area, a qualified and well reviewed electrician, and I didn't bother to shop around for multiple quotes.

In the US you can write off a chunk of that on your taxes, and your local electrical company may have incentives as well.

You recoup the home charging infra expense over the life of the vehicle through lower fuel costs (electricity vs petrol), and that cost is high. I just had a Tesla high power wall charger installed in a condo building for someone, and for a 100A conduit run and conductors (~70 ft including punching through brick exterior wall and mounting conduit to a finished underground parking facility ceiling) to a sub panel from the meter pan, charger install in front of the parking spot, and 20A branch circuit for other loads off the sub panel, total cost was $6k (US Midwest). Utility and local gov incentives covered half of that, bringing the final bill to ~$3k.

As others said, level 1 charging is more than enough for a lot of people. There are also compromises in between level 1 and level 2. The car will likely take pretty much anything you throw at it. So for example if you have 2 circuits to the garage you can gang them to get 240V/15A for double the speed of level 1. Of it might be a 20A capable connection -- 120V/20A (16A continuous) is noticeably faster than 120V/15A (12A continuous).

If you look up the specs you can do your own trenching and place a conduit with a draw string ready to go. If you know the electrician is cool with it you can often pull cables and have everything ready to go (I buy my own breakers and things) and have the electrician install them. I don’t have an electric car yet but I can’t imagine having over $300 or so in labour once I do, using this strategy.

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