Speaking of solar hacks, and that new series of threads on heating the engine block with a plug in device, I seem to remember that in the extreme north there are electrical dip sticks that keep the oil and coolant unfrozen. Seems like a good extension of the sunroof/solar to heat the engine rather than fan out the interior. It could benefit in a sunny but cold day when you park outside and don't have a plug nearby, or store in the/a battery for remote heating say, 5 min before you start the car. Anyone done this?
I don't think there's enough wattage to really do you any good. The OEM EBH uses 400W and takes about 3 hours to get maximal effect, and even then you're still just up to about 110-130F depending upon how cold it is outside.
You already have a solar powered engine block heater, it's the hood, open it and let the heating begin. Honestly you would get not much more heat out of a hood sized solar panel than you would by opening the hood and letting the engine heat that way. It requires an enormous amount of energy to heat anything. On a normal car the considerable kinetic energy of a car moving at highway speeds is converted directly to heat, and the brakes don't really get that hot considering. For this reason, if your going to use a block heater, put it on a timer and have it turn on a couple of hours before you leave, don't leave it running all of the time, that's a huge waste of energy, also leaving a block heater on all of the time can lead to condensation build up in the engine, a lot of aircraft engines get ruined that way every year.
Those dip stick heaters use ~60W and have a small amount of surface area to dissipate the heat to the oil causing the oil in contact to cook. Even if they had ample surface 60w is not enough for an engine heater. Trying to use solar on an engine heater is not a good idea any way (unless you work 2nd shift) because it usually dark when you need the heater in the winter mornings.
I'm in the far north I don't want my oil heated, I want my antifreeze heated. The OEM block heater works just fine, no need to do some crazy dipstick heater thing. Good idea though, maybe the next gen will have a bigger/more solar panels.
Technically the answer is no, not enough power from the cells. But the suggestion is really to what else solar could do for the car. You could have an additional battery to store power just for the engine block as I can't see dragging a plug around. If it could warm up the seat before we got in (like cool the car before you get in) then my wife would be demanding the upgrade.
Feel free to be the first to mount a vacuum tube type solar water heater on your roof or better yet how about a custom hood integration. Do let us know how it works. ( more of an SUV mod with all the roof acreage).
Unlike many here, I won't attempt to outguess Toyota engineers, but if they think it's a good idea, I'd be happy for them to work on it.
Hi richsc, It looks you are in Washington DC, a high latitude place. During winter, the sun sits a lot lower in the sky that during summer. I think the solar power, 60W at peak, becomes 20W or less in your winter. I believe the weak 20W solar power is not effective for any heat devices. Ken@Japan
