Solar charger is convenient for people who usually travel out. But sometimes I want to ask such question “solar charger can work without sunshine?†Perhaps it is a stupid question. But I still want to know the answer. And if they can not work, is it still convenient. You can not use inside and you can not use in winter. Only without sunshine, it becomes rubbish. So is it worth for us to use?
What do you want to do with the power you get from solar? Small solar is good for charging batteries for things like computers and radios. A little larger and you could charge batteries for operating lights and maybe even a television at night. Really large systems can be used to add to the available electric power on a large distribution system.
There are solar panels and then there are Solar panels. The better ones will actually generate a small current on overcast days. Heavy overcast will shut them down too, however. The ones sold for in-car use won't generate power with even light overcast. You get what you pay for. If you are placing the panel -in- the car (on the dash for example), the windshield will decrease the sun's brightness enough that you won't get anything if its slightly overcast. It is worth it to use? If you are parking your car on a surface lot (or the top floor of a parking garage with no roof) when you go out of town by air, it will keep the 12V system charged. The small ones you can buy for in-car use wouldn't overcharge even the Prius small 12V battery. They only put out about 100 mA in full sun. That's less than a "trickle charge" for a 30 AHr battery. It is more than internal losses however, so it will keep a fully charged battery fully charged, even if it's sunny only 50% of the days. Of course it does nothing in a garage or at night (except perhaps attract thieves). Note that these "in-car" panels won't work in the Prius if you plug them into the accy. or cig. lighter socket. Those are disconnected when the car is "off". You would have to modify that or connect directly to the 12V system (on the boost terminal, for example - through a fuse!!).
We have a solar panel and it does charge as soon as daylight appears. We have camped every other weekend through the winter and every weekend in the summer, with 2 months away as well on one holiday and 1 month on the second holiday. We had hook up for about 5 days within this year which of coarse fully charged the battery but other than that we live off the solar panel. A great invention in my view as we really live off free electric with it-Gizmograbber
