The numbers don't add up for solar panels on automobiles, never have,
never will.
This has been proven time and time again.
There is no way it gets even 20 miles per kWh under anything but perfect
conditions and slow speeds.
And the energy from the panels again is under perfect conditions.
It is so light because it has almost no crash protection.
Al
On 10/21/2018 3:09 PM, Larry Gales via EV wrote:
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.
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+
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}
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