Controllable Electric Car Charger?

[Wally999]

I have a Nissan Leaf and Solar Panels. So I'd like to be able to automatically charge the car when the solar panels are causing a net export of power to the grid. I already divert excess power to our immersion heater, using a home made, micro-controller based system that 'watches' the LED on the meter and ramps up the power to the immersion to minimise any export. This has worked well for three years now but on sunny days the hot water cylinder won't absorb all the energy available.

I'd like to do a similar thing with the car. So far I've deduced that no domestic charge point on the official OLEV grant supported installation scheme allows variable charging. So it doesn't make sense for me to get one of these (despite the short term cost saving). I understand that Rolec offer a charge point that has a manually switchable output - which is better than nothing but still not ideal. Does anyone know of a domestic charge point that has an electronic interface that allows the power output to be remotely controlled?

I suppose the alternative is to buy a Tesla Power Wall, or similar, and soak up out excess power that way. Expensive though

 

[brains-lans]

Disclaimer - NOT an electrician, but had BMW i3, have looked in to doing what you are now looking in to but gave up due to change of job and losing said i3.

You might want to look over at some of the threads on speakev [1] about this, there are a few clever people doing things with the mainpine controllers and arduinos [2]. Be aware that american chargers are all tehtered, European are not so you have some signaling differences between the EVSE controller and car in Europe. Learn the specs of the signaling.

I think a lot of this comes down to your programing knowledge and electrical knowledge. You arent going to get what you want via the OLEV grants and most of what they do is all about the metering.

As another thought, the 13a evse the car comes with may have low/med/high settings that can be set in the car giving you lower draw from the car. obviously not in all mode2 evse have this ability to support the requested current signal, but my i3 used to have this ability with the BMW type1 evse. Obviously very slow charge rates compared to a mode3 install but your not going to get 4KW out of solar on your average roof in the UK.

Just remember Car charging points are high current, continuous load. Probably best to get the supply circuit installed to a 32a commando socket by a registered spark, then build your EVSE in a suitable box and supply it with a 32a plug. bits I've used in the past [3]



[1] Anyone Building own EVSE charger. Adjustable amps? (UK) - https://speakev.com/threads/anyone-building-own-evse-charger-adjustable-amps-uk.16812/

[2] OpenEV | Home - http://www.openevse.com/

[3] Welcome - http://evbitz.uk/EVBitz.uk/Welcome.html


Good luck

 

[egg67]

Loxone do one that you can Control from a app for £855, but you would have to get ther mini sever too make it all work think that is £300-£450, so will get expensive

 

[Wally999]

Thanks for the replies. I've come across the Open EVSE but not some of the others. Sadly the Leaf doesn't have switchable current levels - it just sucks up all it can get (up to the 6kW max) - so is not as clever as the i3, apparently. I'll check out the other options though.