If the car is decent as a plug-in electric car, then it still may be worth getting. If the solar panels are sufficiently non-intrusive they may even be close to neutral in terms of the utility of the car, but they do not improve it.
If the car is decent as a plug-in electric car, then it still may be worth getting. If the solar panels are sufficiently non-intrusive they may even be close to neutral in terms of the utility of the car, but they do not improve it.
I think they improve the car not just from a convenience perspective (i rarely drive more than 100 miles a week in the city) but also it helps more of your energy usage come from the sun rather than non-renewable sources you might be indirectly pulling from the wall.
As for the car, I imagine people will burn the energy and more by turning on the air conditioning when they get into their hot car that they intentionally parked in the sun.
Did you glue(/etc) the panels to the roof or did you have to mount them on standoffs?
You could cool it a bit with a Stirling engine and get a little more power from the overheated interior. ;-)
I remember seeing my first solar panel leaning against an old blue and white school bus at a music festival somewhere on the west coast, decades ago. They had a bunch of old auto batteries for storage.
You make it sound like you're using a lot of power in that bus, but an induction cook top is at most 2-3 KW. That is 4 horse power. If you want to crawl at 5 mph that might be enough (but not for a skoolie anyway).
Cars have a huge power-plant under the hood. 100kW per car, at least. All the cars in a city have far more power than the power plant that supplies the city. Think 10k cars (town)= 1 GW. That is a nuclear reactor...
All the cars in the US, 275 million vehicles, at an average of 100KW, have a combined power of 27.5 TW. The total installed electrical power plants in the US are around 0.5 TW. The whole world has only 6 TW of installed power plants.
Cars need a lot of power...
A typical electric car averages 4 miles per kWh. At a speed of 40 miles an hour that's an average power of 10kW - 10% of that 100kW peak power output.
The Ami can charge off 13A 240V in 3 hours (6kW motor and 5.5kWh battery pack), and is useful for a number of duties eg. school runs, shopping, mobility, bad weather.
Obviously the car featured here isn't designed around light weight<->practical charging but I reckon you could make an ultralight design for 4/5 people. The other problem is other larger cars on the road, that's a separate debate from the technical one.
The idea, and especially with the car in the article here, is that your car can charge over the course of a few days.
The power for electric cars is delivered from the battery. The Chevy Bolt for example has a 60kwh battery. If you have 1kw of solar, it will take you 60 hours of sunlight to charge that battery assuming the efficiency of those cells is close to what they're rated for.
The car from the article has a 35kwh battery so around 35 hours of sunlight to fully charge on 1kw of solar. If I drive ~100 miles in the city every week, and the car from the article gets the claimed 200-220w/m2 of solar - It's definitely feasible to recoup your entire driving usage by it just basking in the sun when you aren't using it.
Earth receives 1kW of power from the sun, per square meter. A solar panel has an efficiency of 20%. So under ideal conditions, sun directly at 90%, no shades, you get 200W per sqm. Now, you have shades, less than 90% angles, dirt, etc. On average in the US, the capacity factor of solar PV farms is 25% (includes day/night changes). You will get less on your car, but let's say you do get 25% capacity factor. That leaves you with 1000 * 0.2 * 0.25 = 50W per square meter, 24/7. In a week that is 8400 Wh per square meter. To charge the 35kWh battery once a week, you need 35/8.4 ~ 4 square meters. 4 square meters is plausible. You could say that the car has more space for PVs, but you kind of have to mount them such that they have a decent angle, otherwise their efficiency drops 10 fold.
In the case of Chevy Bolt, if you have a 1kW of PV panels, used in ideal conditions, you would need 1kW * 0.25 * 240h = 60kW. 10 days to fully charge the 60kWh battery. If you manage to install 1kW (4-5 square meters) of panels on a volt at ideal conditions (tilted 30-35%), then you could drive it 200 miles every 10 days.
On the other hand, if you only drive 20 miles a day, you could recharge at a power outlet and 60kWh would cost you 6 dollars. 6 dollars per 10 days, that means fuel cost would be $219 a year. That is $3200 for 15 years. Is it really worth installing a heavy and complex system on the car if you can achieve the same and better results by just laying the panels on the ground, next to the carport?
I am all for integrating solar PV in a lot more things, like house sidings and windows, but putting it on cars is just a PR move.
However, they do degrade noticeably over the space of even a couple years.
I agree with this.
The net grid draw of EVs would decrease if every EV were equipped with solar panels. It's a way of turning the footprint of the car into a source of energy. Not sure how the manufacturing costs work out, but you don't have to replace 100% of the plug-in aspect to substantially reduce the energy costs.
They weigh no more than two kg per square meter including some environmental protection.