Earlier quoted context omitted.
The 3.8 mile range figure is from the Experimental Toyota Prius article you linked. I’ve also used my home rooftop solar PV to charge a Hyundai Kona. Unless this “lightyear one” has solar panels the size of six parking spaces, I suspect the reason they claim so much more than Toyota is because it’s BS.
> The 3.8 mile range figure is from the Experimental Toyota Prius article you linked. Read the article again. You're confusing the small solar panel Toyota has as a current production option with the new experimental solar Prius which has much larger panels. > I suspect the reason they claim so much more than Toyota is because it’s BS. Based on what? The fact that the Lightyear One is being developed by members of So…
Based on what?
When I visit https://lightyear.one/ the default location for the range estimate is "Rotterdam, Netherlands" and the default display is "year max" which is "5311 Wh, 59 km per day"Firstly, the moment you select "Summer" that drops to "2731 Wh, 30 km per day" so the headline figure of 59km is already exceeding even their claimed summer range by almost 100%. So they're fudging figures right from the front page.
Secondly, that's 6.9 miles per kWh, whereas the Tesla Model 3 gets 4.1 EPA-rated miles per kWh [1]. So they're going to be 69% more efficient than Tesla?
A 69% increase in efficiency is a 40% drop in battery cost for the same range. To me it seems unlikely that Tesla, Hyundai, Nissan, Kia, Mercedes, Jaguar and Audi would have all left a cost saving that big on the table, if it was easy to achieve.
Thirdly, [2] says the Lightyear One has "five square meters of integrated solar cells", and that "The 12 km/h added by the solar roof and hood during daylight exposure extends the range as you drive", i.e. 7.4 miles/hour of solar charging. Even assuming they're 69% more efficient than Tesla, that means they're getting 1.08kW out of 5m² of solar panels.
For comparison, if you look at a random rooftop solar installation in California [3] with 40m² of panels, from 9am-5pm the mean output was 4.5kW - so with 5m² of panels, the output would only average 0.55kW. So the Lightyear One claims 96% more output - even making the very generous assumptions that "during daylight" is only the peak 8 hours a day, that the shade and angle of the car panels are as good as a residential rooftop solar installation, and ignoring winter and places less sunny than California. Unless they're using solar panels made of Unobtainium, used in price-no-object applications like satellites, this seems unlikely to me.
Seems to me there are two possibilities here:
1. They've developed an EV 69% more efficient than a Tesla, AND solar panels 96% more efficient than rooftop solar, AND rather than selling either of those technologies to the existing car or solar companies that would very much like them, they've decided to start their own car company.
2. They're quoting efficiency figures for driving at golf cart speeds, or solar figures for noon in the Sahara desert, or daily range figures assuming you'll visit a plug-in charger every so often.
I know which I think is more likely - and my €149,000 will be staying firmly in my pocket.
[1] https://www.greencarreports.com/news/1119556_tesla-model-3-r... [2] https://lightyear.one/lightyear-one/ [3] https://pvoutput.org/intraday.jsp?id=21356&sid=19238&dt=2019...