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Discussion Starter #1
When I want to charge from My Solar PV I need to use the 6A mode on the supplied portable charge supply that comes with the Ampera as it is rare that I generate enough excess elecricity (the free stuff) to go higher. My installed capacity is 2.9KwPeak which means 2.6Kw for a couple of hours in the middle of the summer's day with no cloud. 6A is effectively 1.5Kw and I regularly see that as spare for about the middle 4 hours of the day but until I retire I will not be around to capture it very often. With Economy 7 costing around 5pence per KWH charging at night is the main option. This does not mean I have not generated more electricity than the car has used - just that few of the actual electrons were pushed by them directly.

The main opportunity is after shopping on a Saturday if it happens to be nice weather. I can get back to full before the sun sinks too low in that scenario as I only will have used 8 - 10 miles range. The FIT tariff means the solar PV was a damn good idea in its own right, and driving on sunshine now and then is just a cool bonus. :cool:
 

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I know that J1772-2010 says cars should track the max pilot signal advertised current in real time. This has been confirmed on the Leaf and i-MiEV but I don't think anyone has tried it on a Volt/Ampera.

I know there is a driver in Holland that has set up a system to have their car track their solar PV output. I'm also aware of some other experimentation that I can tell you about on Saturday.
 

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There is a few devices available, one called EMMA and one called ImmerSun, that track your export state and if you are exporting it will redirect your surplus power, that you would have exported, to other devices such as an immersion water heater.

I am looking at the Immersun at the moment as a possible way to automatically divert surplus solar power that would have been exported to the EV charge pod. The device will do it but the issue is whether the car will cope with a reduced current. Not only that but the current would vary from second to second as the house load varies and as the solar generation varied. It could even switch off altogether and then come back on in a very short timeframe and at a very low current (equiv of 50W).

It is an interesting concept but I suspect that either the car or the EVSE won't like than kind of varying supply.
 

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It won't work Paul. You can't 'restrict' current to a device that is expecting or requires a higher amount. You can switch things on and off incrementally like heaters, but ultimately that is why the pilot signal duty cycle exists to tell the car what to pull rather than restricting what is pushed to it.

So you need to get real time power generated from the inverter and use that to vary the EVSE pilot signal. if you want to charge the car directly.

Alternatively you can dump the solar PV straight into batteries and then charge from them later (maybe overnight). I investigated options and it would cost a few thousand to set up though.
 

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Dumping to batteries is a very expensive and it might not even be easy to do given the very strict G83 requirements in the UK. When smart meters are commonplace and there are the safety protocols in place to prevent a backfeed into the grid should the grid be down then I can see it working.

Don't get me wrong... those smart meters will be coming but I suspect that EV integration won't be included in the first wave.
 

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Yes, being totally off-grid is not so difficult or expensive. There is no G83 requirements.

I would love to be off-grid completely. It won't happen as I live in the middle of a housing estate with a small garden and no land but where I lived before we were complete out in the sticks, no footpaths and only recently got a mains gas supply. I have a bit of land there too so I could have had a pretty decent solar/wind set up. Ah... all in the past now but glad to be living where I am.
 

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Discussion Starter #9
Immersun confirmed to me that it must strictly be used only with purely resistive loads such as immersion heater element.
 

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Parax said:
You could run a totally off grid system powered by PV and switch(automatically via relay if required) the car between grid & off-grid supplies.
http://www.wirefreedirect.com/off_grid_homes.asp
Yes the Schneider Xantrex system does this. Can even export once the battery voltage reaches a set level.
 
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