When I look at the Stella Lux and Stella Vie, I get very different results from the negative views of solar powered cars. I start with the assumption that the Dutch students who have won most of the solar car records are not actually lying. So, the specs for the 4 passenger Stella Lux include these:
Length 178 inches Width 69 inches Height 44 inches Weight 826 pounds Battery Capacity 15 kWh Motor Efficiency 97 percent Range on sunny day (Netherlands) 621 miles Range on sunny day (Australia) 683 miles Range at night (on battery) 403 miles Top Speed 77 mph So, if the range at night is 403 miles and the battery is 15 kWh, that translates to 26.8 miles/kWh. Let us suppose that is under ideal conditions, and that a more realistic value is 20 miles/kWh. The solar PV array is 1.5 kW, so a more realistic value under real world conditions is 0.75 kW. In Seattle, where I live, which has about the worst solar potential in the USA, the average solar intensity in July is 6.3 sun hours. So, (0.75 * 6.3 * 20) = 94.5 miles. If we usually travel only 40 miles/day, I could easily see traveling 200 miles on accumulated solar energy, after, say, a week of 40 miles/day travel. And given that 5 months/year we average over 60% of the July values we can travel about 60 miles/day just on stored sunlight from the car. And the 5 passenger Stella Vie is just as efficient. On Sun, Oct 21, 2018 at 12:09 AM brucedp5 via EV <ev@lists.evdl.org> wrote: > > > https://qz.com/1423288/why-dont-we-have-solar-powered-cars-physics/ > The physics of why we don’t have solar-powered cars > October 15, 2018 Michael J. Coren > > [image > https://cms.qz.com/wp-content/uploads/2018/10/image1-e1539387897807.png > The Sono Motors Car > ] > > The nuclear furnace at the center of solar system powers almost everything > on earth. Photosynthesis, wind, and even fossil fuels (once decomposed > living matter) all derive in some way from the star we call the Sun. > > So why isn’t it enough to power our cars? > > It’s all about energy density: how much energy falls on a surface relative > to how much is consumed. We can have solar powered e-bikes that cover > thousands of miles, sailboat drones that cross oceans, even ultra-light > aircraft that circumnavigate the globe. What do they have in common? > They’re > all very light, slow, and consume a trickle of electrons. Solar panels > generate just enough electricity to keep them moving. > > For anything weighing thousands of pounds, like a car, the energy equation > is daunting. A few intrepid carmakers are slapping solar panels on their > vehicles anyway. Few have gotten very far. The German startup Sono Motors > is > adding 330 integrated solar cells on the roof, sides, and rear to give its > vehicle a 30-km boost out of a 250-km (155-mile) battery range. Meanwhile, > Dutch startup behind LightyearOne claims its electric car will “charge > itself.” Although it has yet to unveil a vehicle, potential customers can > put down deposits for a €119.000 ($157,000) car promising to travel 10,000 > to 20,000 km per year (6,200 to 12,400 miles) on its solar panels alone. > > The Sono Motors Car > > Will it work? Don’t bet on it, says Jeremy Michalek, a professor of > mechanical engineering at Carnegie Mellon University and director of its > Vehicle Electrification Group. > > Quartz asked Michalek to estimate how far the best solar panels could > propel > a typical electric car on the market. He broke down the math for us. > > Michalek says about 1 kilowatt (kW) of solar energy falls on a square meter > of the Earth’s surface on a clear day. That’s all the solar energy > available > to collect. For a company like Sono, which says it can convert about a > quarter of that energy into electricity (although that’s very optimistic), > a > full site of panels might generate roughly 8 kilowatt hours of energy per > day (a best-case scenario with four square meters of solar panels). > > Michalek says that’s enough to drive a car like the comparable Nissan Leaf > about 25 miles. But there are many reasons (clouds, poor panel positioning, > dirt), this number will rarely be reached. As for LightyearOne and its > claims that you’ll never need to charge your car in the future? The odds > are > tough. The maximum conversion rate for cheap silicon cells to turn sunlight > into electricity is just under 33%, and more exotic materials that achieve > 44% efficiency are far too expensive for mass production. Without a > revolutionary breakthough in solar panel technology, cars that can recharge > themselves with the sun alone remain fantastical. > > Does that mean putting solar panels on cars is always a bad idea? Maybe > not. > A sunny day can tack on enough miles to cover the average US commute. But > Michalek says that’s an expensive way to extend the car’s range. Anyone > with > a charging outlet can get renewable energy from the wall for a lot less. > Sign up for the Quartz Daily Brief email > Stay updated about Quartz products and events. > [© qz.com] > > > + > > https://www.nbcnews.com/tech/tech-news/driverless-car-hype-gives-way-e-scooter-mania-among-technorati-n919706 > Driverless car hype gives way to e-scooter mania among technorati > Oct. 13, 2018 Driverless car hype gives way to e-scooter mania among > technorati ... In a matter of months, electric scooter startups have gone > from tech oddity to global ... Millions of dollars in funding and billions > of dollars in valuations have made scooters the next big thing since the > last big thing ... > > https://media3.s-nbcnews.com/j/newscms/2018_28/2491731/180709-bird-scooter-san-francisco-njs-1541_0d7cd3431408077aac647d098c7ba8a7.fit-1240w.jpg > > > > > For EVLN EV-newswire posts use: > http://evdl.org/archive/ > > > {brucedp.neocities.org} > > -- > Sent from: http://electric-vehicle-discussion-list.413529.n4.nabble.com/ > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -- Larry Gales -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20181021/8e530e10/attachment.html> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
