Speak EV - Electric Car Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
I have a Peugeot Ion. I also have a 4KW solar array, grid linked.

In order to make sure I am using all the power I generate (rather than exporting it to the electricity company for free, effectively), I am installing an Immersun immersion heater controller. This senses when I am exporting power, and trickles the excess to my hot water immersion heater.

It has an option to switch on an external load (e.g. my car charger) when the export exceeds a certain amount. However, it will switch the charger off again every 30 minutes (so it can see if the export amount is still big enough), and switch it on again if there is still enough power.

Will this power cycling damage the charger, or, even worse, the car or battery?
 

·
Registered
Joined
·
8,106 Posts
AFAIK You cannot use an Immersun to divert to an EV charger. Immersun will only work on resistive loads. Also, the constant switching on and off will increase your battery cycle count and certainly won't do it any good once the state of charge is over 80%.

There are ways to do what you want though but it involves you building your own EVSE that monitors your solar PV and changes the signals to the car so the car ramps down or up the charge rate as your solar PV output changes without stopping the charge.

@Dave Davies and a few others have a system working that does this.

You might be interested in these threads:

Adapting Mainpine EVSE for smart solar charging

Use "surplus" solar PV to charge EV?
 

·
Registered
Joined
·
13 Posts
Discussion Starter #3
The Immersun does have a relay option - you can get it to turn on the relay (and therefore the charger) for (e.g.) 30 mins if the export power reaches (say) 2KW. Then it will turn it off again for (say) 5 mins, rinse and repeat.

It sounds, from what you say, that this would be a bad idea :-(

I'm now reading the threads you linked to - very interesting!
 
1 - 3 of 3 Posts
Top