Level 2 charger home ChargePoint

That's correct. Here's what that same activity looks like with my charger.

 

nice!

how do you drive down the cost per kWh?

 

240V charging is around 5% more efficient than 120V and OP spent at least $600 for the EVSE and installation. How long is ROI in this case?

 

immediate, if it is functional and/or makes you happy

 

Many local electricity providers are promoting use of level-2 chargers by offering rebates on them. In our case, we got $500 twice (a check for $1,000 for installing 2 on dedicated time-of-use circuits). So, check for those opportunities when considering a hardware purchase.

 

The best ROI is to spend $20..50 in parts to hook the factory charger to 220V. Buying a 40A charger just for Prime makes little sense.

 

Not taking advantage of time-of-use discounts and hardware rebates don't either, especially when that same setup can be used for your next vehicle later. You'd be giving up the portability of the factory charger too.

Don't forget that some chargers offer more than just a plug. Being able to control them and get data from an app is really nice. The valuation of flexibility & education is a squishy subject, something each owner must consider too.

 

Taking the cost of the charger into account is kind of short sighted, you are future proofing your home and the next car will probably be able to use it in the future.

 

and if not? Who knows what tech will be in place few years from now - wireless charging? manufacturer's proprietary protocol/plug? utilities insisting on their connected chargers as part of service agreement? Phone chargers is a good example of how thing develop and progress.

 

Not really. The mini-usb chargers are forward-compatible with usb-c. All you need is a $2 adapter. I'm still using my S6 charger with my S9 because of that forward-thinking design.

SAE-J1772 protocol for plug-in vehicles is well thought out already. Doubling of our current 3.6 kW charging rate is already supported by most 240-volt chargers, without any need for an adapter. They automatically deliver power based upon the rate requested from the vehicle. Should someone be fortunate enough to take full advantage of that spec and have a high-power vehicle, a 100-amp line will provide 19.2 kW. A charger with that protocol and input capacity covers it already.

No adapter needed.​

That planning ahead is the result of trying really hard to prevent future capability issues. A standard for household charging benefits everyone involved. Anyone setting up equipment with at least a 40-amp line will be set for many years to come.

Looking at it another way, consider a sustained rate from that 40-amp line. The 7 kW will supply 7 kWh of electricity in 1 hour. Given 8 hours to charge, there would be about 56 kWh delivered. Subtracting charging losses from conversion & transfer, you have roughly 48 kWh added to the battery-pack after that duration. Figuring you'd consume it later at about a rate of 4 mile/kWh, it would provide roughly 190 miles of range... at home from today's technology.

What more do you realistically need ?

 

Exactly! Remember micro-USB, USB A, proprietary Motorola, Nokia, SonyEricsson, older iPod connectors? How useful are those nowadays? Heck, my two GoPros require different chargers!

Pre-wiring your garage for 220V/50A (and may I suggest placing on both sides - apparently manufacturers can't even agree on the EV port placement) - that's future-proofing. Investing few hundreds in a charger that you don't use to its full potential now and that very likely will lacking features to be introduced in the near future is not. But it's only my opinion.

P.S. I believe 50A is not enough for Tesla's supercharging, so there's that.

 

Huh? All you need is a cheap adapter. The charger itself will work with the other devices just fine. USB spec is an industry standard, like J1772.

What features? It will charge your vehicle. Software interfaces are upgraded through a simple download.

At 50 amps, you'll get around 250 miles in 8 hours. How is that not enough for overnight charging? Remember, the topic is home chargers.

 

These EVSE units can be had with a plug, so can be taken if moving is expected.
The cord from the unit to the car is in the range of 25 feet, not gas pump hose lengths. Not reaching a specific car's outlet should be a very low occurrence issue no matter where it's placed.

J1772 is a non-propietary/open source standard. You'll have trouble charging your car if you take it to Europe, but you'll also need adapters for all phone and camera chargers if you go there, and also in China.

There is no set charging standard for wireless yet. A home unit will likely cost twice as much as what the OP paid for their EVSE, and be less efficient. Equipment may also need to be installed on the car.

DC chargers like Superchargers are for fast, on the road charging, not home use. They cost thousands to ten of thousands, because they are actually chargers. The charger for use with AC is built into the car. The EVSE is just an electronic unit that tells the car how much electricity it can supply.