offgrid electric car

Eight months ago I came up my rocky driveway in an electric car, with the<br>back full of solar panel mounting rails. I didn't know how I'd manage to<br>keep it charged. I got the car earlier than planned, with my<br>offgrid solar upgrade only beginning. There's no<br>nearby EV charger, and winter was coming, less solar power every day.<br>Still, it was the right time to take a leap to offgid EV life.

My existing 1 kilowatt solar array could charge the car only 5 miles on a<br>good day. Here's my first try at charging the car offgrid:

first feeble charging offgrid

It was not worth charging the car that way, the house battery tended to get<br>drained while doing that, and adding cycles to that battery is not<br>desirable. So that was only a proof of concept, I knew I'd need to upgrade.

My goal with the upgrade was to charge the car directly from the<br>sun, even when it was cloudy, using the house battery only to skate over<br>brief darker periods (like a thunderstorm). By mid October, I had enough<br>solar installed to do that (5 kilowatts).

me standing in front of solar fence

first charging from solar fence

Using this, in 2 days I charged the car up from 57% to 82%, and took off on a<br>celebratory road trip to Niagra Falls, where I charged the car from hydro<br>power from a dam my grandfather had engineered.

When I got home, it was November. Days were getting ever shorter. My solar<br>upgrade was only 1/3rd complete and could charge the car 30-some miles per<br>day, but only on a good day, and weather was getting worse. I came back<br>with a low state of charge (both car and me), and needed to get back to<br>full in time for my Thanksgiving trip at the end of the month. I decided to<br>limit my trips to town.

charging up gradually through the month of November

This kind of medium term planning about car travel was new to me. But not<br>too unusual for offgrid living. You look at the weather forecast and make<br>some rough plans, and get to feel connected to the natural world a bit more.

December is the real test for offgrid solar, and honestly this was a bit<br>rough, with a road trip planned for the end of the month. I did the usual<br>holiday stuff but otherwise holed up at home a bit more than I usually<br>would. Charging was limited and the cold made it charge less efficiently.

bleak December charging

Still, I was busy installing more solar panels, and by winter solstice, was<br>back to charging 30 miles on a good day.

Of course, from there out things improved. In January and February I was<br>able to charge up easily enough for my usual trips despite the<br>cold. By March the car was often getting full before I needed to go<br>anywhere, and I was doing long round trips without bothering to fast<br>charge along the way, coming home low, knowing even cloudy days would let<br>it charge up enough.

That brings me up to today. The car is 80% full and heading up toward 100%<br>for a long trip on Friday. Despite the sky being milky white today with no<br>visible sun, there's plenty of power to absorb, and the car charger turned<br>on at 11 am with the house battery already full.

My solar upgrade is only 2/3rds complete, and also I have not yet<br>installed my inverter upgrade, so the car can only currenly charge at 9<br>amps despite much more solar power often being available. So I'm looking<br>forward to how next December goes with my full planned solar array and<br>faster charging.

But first, a summer where I expect the car will mostly be charged up and<br>ready to go at all times, and the only car expense will be fast charging<br>on road trips!

By the way, the code I've written to automate offgrid charging that runs<br>only when there's enough solar power is<br>here.

And here are the charging graphs for the other months.<br>All told, it's charged 475 kwh offgrid, enough to drive<br>more than 1500 miles.

January

February

March

April

2026 update: After upgrading my inverter and running conduit, the car is<br>finally charging at a faster rate of 16 amps, and the car typically<br>charges 25% per day. That seems to be plenty for my needs.

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Last edited Wednesday afternoon, June 17th, 2026<br>Tuesday afternoon, April 22nd, 2025 -->