EV charging by solar only
Discussion
Works for me based on 3kw of panels and similar mileage in a model 3. I fallback to some Octopus Agile use when necessary. Low mileage means I can choose to wait for cheap Agile rates.
I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
I have a Zappi charger integrated with our solar system and can charge solar "only" which even in winter there're days when you can charge just by solar - albeit very slowly. I do 4-5k miles per year. The Zappi can supplement solar with grid power depending on settings.
That said, I didn't get solar specifically for the car - its main use is to save costs heating/powering the house.
Charging the EV is a bonus - mind you, it's not free as I get 9.5p selling back to the grid so effectively 9.5p/kWh into the car.
My maths tells me a battery isn't cost-effective for my situation.
Sam
That said, I didn't get solar specifically for the car - its main use is to save costs heating/powering the house.
Charging the EV is a bonus - mind you, it's not free as I get 9.5p selling back to the grid so effectively 9.5p/kWh into the car.
My maths tells me a battery isn't cost-effective for my situation.
Sam
FranFran said:
Works for me based on 3kw of panels and similar mileage in a model 3. I fallback to some Octopus Agile use when necessary. Low mileage means I can choose to wait for cheap Agile rates.
I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
I was thinking that, the way around that would be to use a granny charger. It would be slow, be then again the amount of solar is likely to be low anyway. I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
ashenfie said:
FranFran said:
Works for me based on 3kw of panels and similar mileage in a model 3. I fallback to some Octopus Agile use when necessary. Low mileage means I can choose to wait for cheap Agile rates.
I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
I was thinking that, the way around that would be to use a granny charger. It would be slow, be then again the amount of solar is likely to be low anyway. I do think a small amount of battery storage would make things much easier through the winter months though. There are many days where generation is 0.5 -> 1KW which falls below the minimum charge rate (1.2KW) so the car is pulling some power from the grid additionally. Agile rates tend to be higher during typical sunshine hours.
We first need to hear the size of the instal that the op is considering. Might be cheaper to pay to lay on power to the garage.
There were some loons direct charging Nissan Leaves from solar panels years ago.
Charging a 300V (?) DC battery with a current limited DC supply is a pretty basic task, if you've got direct access to the battery terminals or understand the controls.
The leaf is kind of different because the whole electronics of it kind of got into the public domain and picked apart online.
Plus of course the interface was Chademo in those days.
Lots of interesting stuff online still, but it's dangerous sparky stuff if you don't understand it.
As was said at the time, a house battery charged by the panels, feeding a granny charger via an inverter is not the most elegant solution, but it's more versatile and can pretty much be plugged together with no great technical knowledge.
Bear in mind that you can throw a lot of errors on many petrol cars just by charging the 12V battery wrongly, I would not be even slightly surprised if buggering about with non-standard chargers bricked an EV.
Charging a 300V (?) DC battery with a current limited DC supply is a pretty basic task, if you've got direct access to the battery terminals or understand the controls.
The leaf is kind of different because the whole electronics of it kind of got into the public domain and picked apart online.
Plus of course the interface was Chademo in those days.
Lots of interesting stuff online still, but it's dangerous sparky stuff if you don't understand it.
As was said at the time, a house battery charged by the panels, feeding a granny charger via an inverter is not the most elegant solution, but it's more versatile and can pretty much be plugged together with no great technical knowledge.
Bear in mind that you can throw a lot of errors on many petrol cars just by charging the 12V battery wrongly, I would not be even slightly surprised if buggering about with non-standard chargers bricked an EV.
As others have said it won't work. You can't trickle charge an EV it needs a minimum of a about 1.5kW and at that level it's pretty in efficient as 100-300W of that is just going into keeping the car switched on to receive the charge. Spend the money on mains working to the garage rather than solar.
GT6k said:
As others have said it won't work. You can't trickle charge an EV it needs a minimum of a about 1.5kW and at that level it's pretty in efficient as 100-300W of that is just going into keeping the car switched on to receive the charge. Spend the money on mains working to the garage rather than solar.
And an additional thought along these lines, if the sun goes behind a cloud even briefly and the power being generated drops below the required minimum, the charge will obviously stop. It will not automatically start again when the sun 'comes out' so you'll have to keep restarting the charge manually. PITA.So I'd say battery storage would be required for an uninterrupted charge.
Caddyshack said:
They said garage with no power, I d assume that it isn t at the end of their garden.
Yeah but it can't be that far away you've got to hike every time to use the car. Extension reel (good quality to avoid fires etc.) or proper socket install has got to be cheaper and more useful than solar panels.this is the eutopia isn't it. Drive an EV that's been charged purely by the energy you've produced at home. 'free fuel'
I priced it up a long time ago and the break even was a 3kw system, just on the garage roof (was pitched nicely too) to keep costs down it would have been a solar only (no trip over to grid).
Equipment and prices have improved massively since 2017 but well do-able
I priced it up a long time ago and the break even was a 3kw system, just on the garage roof (was pitched nicely too) to keep costs down it would have been a solar only (no trip over to grid).
Equipment and prices have improved massively since 2017 but well do-able
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