this post was submitted on 16 Jun 2025
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Good video. Accurate information.
Two notes:
For North American homes: I agree with the overlooked value of a downrated circuit for EV charging, but I don't think he talked about a possibly better option for downrating: Using an existing 120v circuit (at whatever current rating) already wired in the garage . Remove the outlet, install EVSE (charger), and swap the breaker for a 240v one (at a current rating matching the original. So if you have a 120v 15A circuit (white romex) you can use the exact same wire for a 240v at 15A. If you have a 20A (yellow romex) you would end up with a 240v 20A. You get more than double the speed of charging with zero new wires added, only changing the breaker and removing the old outlets. Note: If you have multiple outlets in your garage all fed from this same circuit, this would mean all of your outlets in the garage are now 240v and not usable for regular 120v items.
He didn't like Smart chargers. Thats a valid opinion, but smart chargers can do some nice things that I like. Some will also talk to each other if you have two chargers, such as if you have two EVs. They can be configured to share the same wire to the breaker box, so you can plug both cars in at night, one car will charge, then when that is complete, the other will charge automatically without having to unplug one car and then plug in the other. It will charge the least charged car first ensuring the best balance of charge to both cars assuming both cars can't be charged to full in one night. If you have solar panels, some smart chargers can talk to the solar system and be instructed to only charge when there is excess power that would otherwise go to waste. It can do this automatically so if clouds go overhead and not enough juice is available from the sun, the charging stops. As soon as the clouds clear and there is an excess again, charging resumes automatically. For outdoor charging, you can also configure most Smart chargers to only charge you authorized cars. So you don't need to worry about someone rolling into your driveway when you're not home (or a bad neighbor) and running up your electricity bill.
A 240V 20amp circuit I think would meet the needs of 99% of commuters in the US. If your average miles/kWh is around 3.3 and you're charging at 80% of the 20amp breaker limit (as you should be), even factoring in 10% losses in power transmission, you're still charging somewhere around 11 miles per hour. Easy 100+ miles overnight with zero infrastructure change outside of a couple wire nuts and a cheap charger. Hell, depending on local codes, you might get away with slapping in a nema 6-20 receptacle to make it even easier...
If you do a receptacle, you've got to then do a GFCI. Check out the price difference between a GFCI breaker and one that isn't. If you hardware the EVSE, you don't need GFCI because GFCI is built into nearly all EVSE. If we're doing this exercise to keep low costs, adding GFCI outside of the EVSE jacks up the price.
Fair enough! Anyone with existing 240v receptacles of any kind is a lucky duck, regardless.
Are they somehow more expensive in the US? 40A 230V rated ones cost something like 30-50 € around here which doesn't feel that expensive to me. I'll admit it's considerably more expensive (~4x the price) than a standard breaker, but it's still more like a rounding error in overall costs.
Although EVSE's projection doesn't require you to periodically trip the GFCI so it doesn't get stuck, which is a major plus.
In my suggested hardwired 240V 20A EV charger the total parts cost is just the regular breaker on the left at about $18.
The suggested solution you had of putting an outlet in would have parts cost of $119 + the cost of the GFCI breaker, the outlet and the receptacle cover. So that solution is 660% more expensive.
Ok, so the US-style GFCI-breakers are indeed a lot more expensive than similarly rated DIN-rail alternatives. TIL
If it makes you feel better, I was shocked (pun intended) to learn this too, and I live here.