Indeed - numbers don't lie. A decent family car has no more roof surface than max 15 x 6ft or about 90 sqft. At current (low cost) solar panel efficiency, the max you could get out of that is around 12W per sqft (at perfect angle of irradiation, so in practice, a lot less!) which means you might get around 1kW from this roof, or about 5 kWh per day since the sun moves along the sky so you can count on approx 5 full sun hours each day. That means that if you drive less than 20 miles avg per day, you can drive on the solar roof alone if you keep it in full sun all day. No parking under trees or in covered parking garage or behind a building. If you want to do a 200 miles trip (besides battery capacity concerns) you need to park and charge your car for 10 days straight to accumulate the approx 50 kWh that is needed to go that distance. Question is if your pack will contain that. More likely your pack will be half that size, you you can charge 5 days straight and go 100 miles at freeway speed, maybe this is sufficient to do 200 miles at 25 MPH but who wants to sit for 8 hours doing residential street speed?
BTW, which car has a flat 90 sqft straight roof surface and is aerodynamic? Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: cwa...@proxim.com Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of Lawrence Rhodes via EV Sent: Friday, September 26, 2014 3:52 PM To: firstname.lastname@example.org; ev-requ...@lists.evdl.org Subject: [EVDL] Building a true road going solar EV. Help everyone. It seems that the numbers don't lie. There is now a proven design which will allow you very good range with a small battery pack and good speed. The Stella. My next project after the electric motorcycle will be a road going vehicle with a top of solar panels. The Stella proves ugly is good at least for a family solar car. I'm going to build mine using a Leaf battery pack. It will be heavier than the Stella and have more battery capacity but that is not set in stone.I will make a tear drop tube frame and cover it using light plastic or abs sheet. The vehicle will look like a tadpole with a wide tail. The Stella proves you can have a very blunt front edge and still have efficient CD. I'll use four hub motors. Seating for four or 6 will be slightly recumbent. Small space in rear for storage. It will be very similar to the Stella in looks but a lot simpler. I don't want to reinvent the wheel. It would be nice if it could cruise at 25 or thirty mph and still charge the battery. However I'd be happy if it would charge in a day of bright sunlight and have a 200 mile range. Now to source the parts. That's where the group can help. The Stella used individual solar panels laminated into the roof of the vehicle. What is the best to use to get at least 1.2kw? Bicycle hub motors. What are the most efficient for the money? Using four if they are all 10000 watt motors this should do the job for freeway speeds. A Rudman charger of some sort unless the solar panels are enough. Simple disc brakes when not using regen. I'll be making the frame from bicycle chromoly. I'm going to try to get Zzipper to make the windshield.. All comments are welcome. Lawrence Rhodes -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140926/42ea 0963/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)