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Solar power on the roof of an EV car seems like an obvious play. And yes some energy can be derived this way. But it's important to understand the limitations o
by bruce511 17d ago
Solar power on the roof of an EV car seems like an obvious play. And yes some energy can be derived this way. But it's important to understand the limitations of physics.
When the sun is directly overhead we get about 1kw per square metre. Very good panel effeciency is about 25%. ) I'm rounding a bit to make math easier.) The average car footprint is maybe 6 square meters. Obviously a lot of that is curved away from the sun, or is glass. 4 square meters here is perhaps a reasonable starting point.
Which means if we plaster the car with solar cells, we might get 1kw of output in pretty optimal conditions. Perhaps 12 hours of generation depending on latitude, time of year, and so on.
Most EV cars have 30 to 80 kw batteries (some more). So 12kw of charge per day is not nothing, but also not enough. Given pesky things like shade (from tall builings or trees), undercover parking, clouds and so on, daily average is much lower.
Solar film in general is great. But current pricing makes it cheaper to just install regular solar panels in most places. Less portable maybe, but more (financially) efficient to generate/store/charge as we currently do.
On the other hand the aesthetic of a solar panel car roof is very cool, and maybe covers the aircon power requirements on a hot day.
- brador 17d agoPark in an open space. Auto unfurl the 7 hex panel solar collecting roof array. Solar doesn’t have to be limited to the car roof footprint.
- thomasmg 17d agoRight, but for a fan, it would work. Cars heat up mostly in direct sunlight. The solar panel could be wired directly to a fan. This would also prevent heat death of dogs and forgotten children.
- margalabargala 17d agoA solar panel would obviously not cover the usagebof a consumer car while it is being driven. Consumer cars spend most of their time not being driven. If someone commutes 10 miles to work each day, they would nearly never need to charge the car.
- LoganDark 17d agoThat is, if your car has frequent access to sunlight. Mine spends most of its time underneath a cover, some others spend most of their time in garages.
- thelastgallon 16d agoSolar canopy for parking lots is a thing. Individual lots as well as large lots.
- LoganDark 16d agoI don't have permission to do anything to the parking lot, it is an option for people who can though.
- Lutger 17d agoIt doesn't need to cover the usage, or even be able to fully charge it when sitting idle parked. There are two ways to make it viable: - adding a bit more range to soothe the range-anxiety people - adding enough kWh in its lifetime to offset the cost plus extra If its not adding an off putting amount to the cost of purchasing the car, it should be commercially viable.