I’ve spent much of my life building cars. One of my earliest memories is sanding the wooden spokes on a 1926 Ford Model T. My teenage years found me hot-rodding early Camaros, Chevelles, and a 1932 Chevrolet. I have always enjoyed building motors. I went to engineering school, and worked for Ford Motor Co. as well as Jaguar Land Rover in England, but never found creative outlets for my motor-building passion.
Then I found electric motors, with their “clean” design and alternative fuel possibilities. This interest combined well with my enthusiasm for renewable energy—for the last 15 years, I’ve been passionate about off-grid power. I’ve designed and installed about 30 off-grid PV systems. I’ve also retrofitted some golf carts with PV modules. So by the time I was ready to build my electric vehicle (EV), I had it all planned—not only would I convert a gas-engine vehicle to electric, but I would add a PV system to supply the energy for traveling and off-grid camping.
Life in the Slow Lane
I chose the Volkswagen Transporter for its large roof surface, which could accommodate several PV modules on a tiltable rack. I spent many hours in the design phase to figure out how best to make a watertight installation. My wife Kira pieced together canvas to make a large tented area underneath the array—there’s enough headroom to stand up. She also made a door with a screen and removable window for a rear exit.
The array consists of four 305-watt LG Solar modules, for 1,220 watts. One edge of the array is hinged in the front of the van, and actuators (one on each side) tilt the array up to 40°, creating a large space above the van. Being able to move the van allows positioning the array to receive great solar exposure. When we stop driving for the evening, we can orient the array to capture the evening sun. Facing the array east in the morning ensures that the array gets the best exposure at that time.
Four Drok DC/DC converters boost each module’s voltage from 40 Voc to 50 Voc for better power transfer from the modules to the batteries. These converters are wired in series for about 200 Voc. The array generates 8 A total (at 150 V) into the battery. I can adjust the converter output voltage and manually power point track the modules.
Our family has lived with a 1,200 W PV system for years, and we know how to use electrons wisely. Camping loads, such as our small Dometic fridge, a clamp-style work light with a 7 W compact fluorescent bulb, and a 1,200 W cooking element, also consume energy from the array. Other loads include a water pump under the sink and a swamp cooler. However, our daily camping load (about 800 watt-hours) isn’t much compared to what the van uses for propulsion.