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.
A 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.
That 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.
Right, 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.
Uni-Solar used to (or maybe still does?: http://www.uni-solar.com/products/commercial-products/pvl/in...) make flexible 3-mm-thick self-adhesive solar film, and if I remember correctly it could be installed on a roof without a permit, although it still required a permit for the electrical connections, so it probably didn't make things easier.
With some states only requiring UL listed inverters for small plug-in systems, it could become a more viable product.
"Some day, homeowners eager to produce their own energy might not line their roofs with solar panels. Instead, they’ll spray-paint them with a mist full of electricity-generating solar cells."
With plug-in solar initiatives around the world, this will be a gamechanger. If there are superlight, plug and play or DIY install products, everyone can produce energy. No surface left behind!
Oh, I meant that the film's already visibly transparent. I was wondering if you could potentially capture a bit more energy by reflecting the transmitted light back through the PV layer a second time. Not sure if this would work in practice though.
https://solarwindow.com/electroflex/
There are already multiple solar roof cars. This should make it easier to integrate solar into these designs.
This is the worlds cheapest SOLAR CAR: https://www.youtube.com/watch?v=Hk6aTKV-des https://www.solarkycar.com/
Alin Chinese Electric Car with Solar Panel CE Approved Electric City Cars, US$1,500.00-2,000.00: https://alinmachinery.en.made-in-china.com/product/zZHTdphPH...
Chinese EV company tests flexible solar sunroof for 50 miles of additional range per day: https://interestingengineering.com/transportation/hongqi-per...
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.
A 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.
That 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.
Solar canopy for parking lots is a thing. Individual lots as well as large lots.
I don't have permission to do anything to the parking lot, it is an option for people who can though.
It 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.
Right, 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.
Moving hot air around with a fan in a closed car will save dogs nor kids from overheating.
Nit: missing a 'neither' before 'dogs'
Park 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.
Uni-Solar used to (or maybe still does?: http://www.uni-solar.com/products/commercial-products/pvl/in...) make flexible 3-mm-thick self-adhesive solar film, and if I remember correctly it could be installed on a roof without a permit, although it still required a permit for the electrical connections, so it probably didn't make things easier.
With some states only requiring UL listed inverters for small plug-in systems, it could become a more viable product.
This is vaporware. I've been hearing about this sort of technology for the last 20 years. Hope to be proven wrong someday.
Here's a similar article from 2013, talking about a paper from 2005:
https://www.fastcompany.com/1681384/you-may-soon-just-spray-...
"Some day, homeowners eager to produce their own energy might not line their roofs with solar panels. Instead, they’ll spray-paint them with a mist full of electricity-generating solar cells."
Seems like window blinds might be a nice use case too
With plug-in solar initiatives around the world, this will be a gamechanger. If there are superlight, plug and play or DIY install products, everyone can produce energy. No surface left behind!
Can I get it installed on my car like a vinyl wrap?
Vinyl wraps
- can be cut to arbitrary sizes
- can be stretched a bit to make them fit non-flat, non-cylindrical surfaces
I doubt either of these can be done with this without breaking the solar cells and/or the sheets.
Specialized shapes for each car type probably could be made, but those, not being flat or rollable, wouldn’t be easily distributable.
I don't know if it can be DIY, their website says manufacturers can integrate into their workflows.
Transparent? Curious, would installing a reflective backing improve its efficiency?
Looks like they are also working on transparent. In development.
https://solarwindow.com/liquidelectricity/
Oh, I meant that the film's already visibly transparent. I was wondering if you could potentially capture a bit more energy by reflecting the transmitted light back through the PV layer a second time. Not sure if this would work in practice though.