Building an OpenEVSE kit 1

Описание: This is an Arduino-based electric car charge station that has a lot of features not found on most commercial chargers. When searching for a charger that had stop and start times, along with an adjustable charge current, this one fit the bill perfectly. And since its firmware is open source, it is straightforward to add additional capability such as wireless monitoring and control.

Because of wiring limitations in my garage I won't be able to use its full capability as a 50 amp charger, but will still be very happy to have 240V and 16 amps, up from the normal wall-outlet charger that comes with the 2015 VW eGolf (120V, 10 amp). I barely have the car home long enough during weekdays to fully recharge overnight, so this was a primary motivation for the upgrade.

In addition I will save $20-$30 per month on my electric bill since my electric company has a lower rate between 10pm and 8am, and this should pay for the charger and necessary electrical bits in 1.4 years. Using the original charger wouldn't provide this price benefit since I can't fully recharge in those 10 hours (I use about 14 kilawatts per day). I did some back of the envelop math and charging at the lower rate for 10 hours using the default charger and then having a decent amount of usage at the higher rate outside that window cancels out any benefit. But if your normal commute allows a full recharge in a low electric rate window, simply buying a regular 120V timer for the default charger would be a super cheap option.

I'm doing the electrical installation myself and that makes all the difference on this 1.4 year payback period. If I had to pay for an electrician to do the hookup, saving only $20-$30 a month might add years :) As always, I learned how to do the electrical installation by watching YouTube videos!