Charging an EV from dedicated solar only system?

The Dreamer

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I’m thinking of building a garage/workshop away from the house, and was wondering about the feasibility of sticking some solar panels on the roof and using these, and these only, to trickle charge an electric car. Is this possible?

There’s no power available near the spot I’m thinking of, and running it there would be tremendously expensive.

So I’m thinking of throwing up some 2nd hand panels to give a maybe 2 or 3 KW system, an inverter to match, and simply wiring up a charging point to it. Would that work? Do I need some way of dumping excess energy somewhere?

Or is this not even possible?

Anyone know where to look for information on creating such a project?

TIA
 
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There are plenty of "12V solar trickle chargers" on the market - just google it
 
There are plenty of "12V solar trickle chargers" on the market - just google it

Sorry, I didn’t make myself clear. I’m talking about charging an EV rather than just keeping a 12v battery topped up. Title, and post, duly edited! :smashin:
 
You will need enough output to meet the minimum charge for your EV - most need around 1,6kW to start charging. Then you need a “charger” that will be able to modulate its output to match the output - chargers like the Zappi can do this. But you still may need some battery backup to smooth the output as your car may not like power being suddenly removed when solar output drops. Maybe have a chat with the technical department at MyEnergi and others to see what they think.
 
Found this write up
Yep. I’d found that, but it talks more about a complete solar system, integrated into one’s home grid supply, (which we already have), and goes on to say…

There are EV solar charging systems available, but no dedicated standalone solar panel car charger is available just yet.

Which is why I was wondering whether it’s even feasible. I mean, I’m sure it is, but at what cost, and what do I actually need to consider?

It may be simpler to just accept that I’ll have to move the EV’s around to both charge from our existing point - but would have liked to have our more rarely used EV to simply be hooked up to a few solar panels (effectively) and so benefit from ‘totally free’ energy - as opposed to using a combination of solar and grid as we do now.
 
You will need enough output to meet the minimum charge for your EV - most need around 1,6kW to start charging. Then you need a “charger” that will be able to modulate its output to match the output - chargers like the Zappi can do this. But you still may need some battery backup to smooth the output as your car may not like power being suddenly removed when solar output drops. Maybe have a chat with the technical department at MyEnergi and others to see what they think.

I had a feeling that a minimum output/input would be required - which probably explains why no one has developed a standalone solar charger, for the U.K. market at least. Even with a 4KW system, we frequently sit below that threshold with a spot of cloud, and we can forget it in the winter months.

Seems like I might be barking up the wrong tree with this idea, and we’ll be better off either just running power from the house where we’re already increasing our solar from 4KW to 9KW, or simply moving the cars around as required - not exactly a major hardship!

Oh well!
 
It's 1.4kW minimum. That's the lowest our Zappi2 will go to before it displays a countdown to stop charging. You would definitely need some battery storage to continue charging through sunny spells and cloud. I do not see why it wouldn't be possible, simply by disabling the cut-out feature from the inverter (it has to have this by law so there is no upstream power during a power cut), but I dare say not all inverters are capable of this. Another thing is you may need a ground to dump surplus energy to be safe. Thing is all this could get more expensive for this type of off-grid set-up compared to a connected one. I believe having everything connected, as you say expanding the existing system and connecting the house and garage, would maximise your flexibility and provide the opportunity for 13A sockets in the garage for appliances and tools, and lighting.

And 9kW would be awesome! If we had that amount of solar PV here, that would probably cater for all of our energy needs in the warmer half of the year, and many sunny days in winter.
 
It's 1.4kW minimum. That's the lowest our Zappi2 will go to before it displays a countdown to stop charging. You would definitely need some battery storage to continue charging through sunny spells and cloud. I do not see why it wouldn't be possible, simply by disabling the cut-out feature from the inverter (it has to have this by law so there is no upstream power during a power cut), but I dare say not all inverters are capable of this. Another thing is you may need a ground to dump surplus energy to be safe. Thing is all this could get more expensive for this type of off-grid set-up compared to a connected one. I believe having everything connected, as you say expanding the existing system and connecting the house and garage, would maximise your flexibility and provide the opportunity for 13A sockets in the garage for appliances and tools, and lighting.

And 9kW would be awesome! If we had that amount of solar PV here, that would probably cater for all of our energy needs in the warmer half of the year, and many sunny days in winter.
Yes, this is conclusion I’ve come to really - simpler to connect to the existing system - and cheaper!

The addition of more solar to bring us up to 9KW has been delayed again - only by a week this time, so by mid September the extra solar should be on line. It should see us being pretty close to self sufficient over the summer and shoulder months. 🤞
 
I've just found this from Solis. Might be handy for others looking at this thread.
 
Are you not using your car during the day ?
 
Are you not using your car during the day ?

Not sure if that's asking me, but as the OP, I'll answer....

We tend to use our EV twice a week for my wife's work, and then weekend trips to the local NT or EH properties that abound around here. So it's usually sat on the drive for 3 or 4 complete days a week - plenty of time to be charged by solar, even at the minimum charge of 1.4kw per hour.

Though the initial query was more to do with a potential second EV, which, if we use it like the XC90 it'd be replacing, would only get used once a week, maybe two tops - and for longer journey holidays (we've only flown for holidays twice in the last 20 years)! So a longer 'trickle' charge would be more than adequate, no matter how big the battery of such a potential car might be.

My own car is a 3.7 litre petrol gas guzzler, that gets very little use - just a commute to work once a week-ish, so a tank full of petrol still lasts well over a month - I may go over to electric if the MG roadster is actually any good.

TL;DR - barely!
 

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