I always wanted an electric vehicle. Not because they are quiet, fast or fashionable, but because I can charge it off the sun! I built a golf cart with a panel on top and hauled wood for years with it. The electric chainsaw ran quite well off the 72-volt bank. What a workhorse! Just park it in the sun.
I realized that if I built a highway-legal vehicle with a good amount of solar on top, I would really have something valuable. I had no idea.
Sizing Solar Panels for Electric Vehicles
The time is here for solar power to make its way to our vehicles. The state-of-the-art panels pose no weight limitation. At 6 pounds per 150 watts, thin flexible solar panels will weigh 600 pounds but give you 15 kilowatts! This is enough to directly drive from the sun.
However, the surface area is a limitation, because that much solar would require 10 feet around the vehicle on all sides. The solution, ironically, is a mechanical engineering question of how to accordion-style fold these panels to conveniently open them for charging while the vehicle is at a standstill.
Considering Design Options for VW Bus Solar Conversion
My first rendition put 1,200 watts on top of the vehicle. I could easily hinge the array in the front of the vehicle for solar tracking. I made a convenient tent space under the array to mimic a VW Westphalia camper design.
Now the 1973 VW transporter is a camper! If I work it, tracking the sun all day, the 1,200-watt array will fill the 14 kilowatt-hour lead-acid battery bank for a 40-mile run. Not even trying around town, there is 20 miles of range waiting just from natural solar exposure — no plugs necessary. My family and I did 1,400 miles this summer using up the month of July. The viability is here!
Brett Belan lived off-grid in California for a decade before moving to Ashland, Oregon, and co-founding Apparent Energy, an engineering company dedicated to improving our electrical systems. He spends his free time building improving a converted 1973 Solar-Electric VW Bus. Follow Brett on Facebook and Instagram, and read his article in Home Power magazine.