I remember reading about this Swedish dude who added 2 solar panels totaling about 1 kW to his hybrid station wagon. Even though the sun doesn't really shine all that much there, he still got enough power out of it, to never have to charge his car for his 20kmish daily commute.
No he didn't. Sweden gets ~2.6kWh/day per kW of solar panels. Malmö is at 55N latitude. If he put the panels on the car I hope he had a decent anti reflection coating because at that latitude he could be looking at 25% reduction in performance from the incident angle.
A purpose built EV gets something like 270Wh/mile in near perfect conditions little alone in a colder climate like Sweden.
12.5 * 270 = 3,375
So we've made absolutely every assumption greatly in his favor and we're already 750Wh short.
I don't remember the exact details, it's possible that he charged it over the weeked (or just didn't use it, thus getting 2 extra day of charge).
You can play around with assumptions, like what if it was driven in stop-and-go traffic at very low speeds? Then your quoted 270Wh figure might be lower.
But anyways, with these general conditions, with the numbers you quoted, and with a 10 kwh battery (aspull), you'd be looking at a net loss of 775Wh/day, which means you could go 13 days between charges.
The point I tried to make, is that solar panels on hybrids/EVs add a lot of practical value to people who can't charge at home/work, and it's not just meaningless greenwashing.
Also that 2.6kWh figure is a yearly average probably, sunlight varies greatly over the year.
> I remember reading about this Swedish dude who added 2 solar panels totaling about 1 kW to his hybrid station wagon.
I want to see a picture of that.
Apparently 1 kw fits on an extended box van [1]. But I don't now how you'd do it on a wagon without making it look like some sort of Burning Man art car.
My exact numbers might be off (which is kind of a problem it seems on HN), but the point still stands - you can add practical amounts of range by having the car just sitting there, even in places where there's not that much sunlight.
Besides, I just checked out panels, and there's a lot of 500w ones that are appx 1mx2m, these station wagons are huge, easily 2m wide and 5m long, half of it a flat roof, so its not outrageous.
Won't work for most cars in cities, as they will be parked in indoor/underground garages, so no solar to speak of for their parking time, and the bit of solar you get while driving will maybe power the lights/electronics/audio system at most.
(Driving a full EV, but needing to charge 30+kwh/week, and my small (but larger than a car could fit) home-solar only provides max 20kwh/week in spring/summer.
A lot of car parks have chargers. Wiring up low wattage chargers is no big deal, considering AC chargers are just wiring+breakers. Considering cars will spend a long time here, large wattages are not needed, you could wire up a multi-story parking lot for chump change, and the entire wattage would be still less than a DC fast charger serving half a dozen cars.
