It wouldn't be able to go very far underwater, though, because the rays of the sun don't penetrate very deeply into the ocean. Of course, maybe when the submarine isn't being used it could sit above the water and collect the solar rays and store them in some kind of battery, and then when it goes underwater it would use the stored electricity-- Rubi, Oct 27 2003 Now, what you could do is spread tiny solar batteries all across the surface of the sea, then have your submarine harvest the batteries for its power. No, wait, that would be a whale.-- DrCurry, Oct 28 2003 Wasn't that the evil secret weapon in the movie "XXX"?-- onecentJay, Oct 28 2003 When it is charging, all that sunlight beating down might tend to make things hot on board. Best install a screen door just in case.-- krelnik, Oct 28 2003 [Rubi]:
Thatd be a great idea for robotic subs. Your idea is completely sound, although itd be very costly, and probably restricted to sunny areas.
During the day the sub could loll around the surface of the lake (or ocean) and extend its solar panels. Extendible solar panels would give the unit quite a large surface area (as large as needed) and provide plenty of power to recharge the sub batteries for a night of automated exploration. Whilst at the surface, the sub could also uplink with a satellite and dump the previous nights data.
Despite a solar panels small power output, if running constantly it can add up to a substantial amount. For example, I just read at evword that a Jeep covered in solar cells could generate about 500 watts, enough to provide power to drive it over 5000 km in a year (at 20% efficiency solar cells and 80% efficiency electric drive). The sub would not have the same restrictive surface area as a jeep, or structural limitations for a rigid PV mount (as the panels could be supported by flotation).-- TIB, Oct 28 2003 tib, just too point out water is more viscous than air-- engineer1, Feb 12 2004 DrCurry, you were onto something! A plankton powered submarine! And I ask you: Why not? If a whale can, why can't a machine?-- pashute, May 05 2010 random, halfbakery