And it isn't heat which they conduct, it's in the name, solar. Light waves from the sun being processed by photovoltaic cells are what makes the energy so even on a cloudy day energy can be stored.
depends on the type of panel. some are photovoltaic (generate electricity) other merely pass water through capillary tubing to provide hot water.
oil supplies - well depends on what you listen to. current estimates put north sea supplies at 30ish years - better technology in the near future will increase the extraction so give some more time - some old fields are currently being reopened. alska/north canada - ooooo - oily sand - and trillions of barrels worth by the last estimation. west of shetland - another new source - uncertain quantites or production life. siberia - same deal. khazakstan - same deal. the oil companies are very shrewd at this game.
other technologies other than oil.....
coal - fine to make synthetic oils and oil-based products through the reformation process, but coal is given a life expectancy of 300 years.
gas - same deal, only around 50 years. unless we use biogas (see below)
nuclear - an alternative, yes, but not clean or renewable - approx 3000 years of use
at current levels
biofuels - fine and dandy - carbon neutral (same amount of CO2 released on fermentation and/or combustion as is absorbed during growth) -
but need to give up arable and livestock land to provide the crop space - difficult with an ever growing world population.
geothermal - way, way too expensive to be even remotely feasible in most places as a method of producing electricity rather than just hot water. the drilling depths to get the water to vapourise are unfeasible.
biogas - fine if we can find enough organic waste to decompose. in theory each plant would provide enough power to run a small village.....or heat a farm as is the current practical use.
hydroelectric - works incredibly well in the correct geographical location. but there is an environmental trade off. look at the three gorges dam. the supply lake was created by flooding an area roughly two thirds the area of mainland britain....
wave - great if we can ever get the stupid generators to actually work properly and produce a sensible output. however with these things dotted all over the seascape its asking for trouble from shipping/sailing...
tidal - not many places provide a decent tidal current to produce a decent power output using current technologies.
wind - turbines are getting better all the time. but again people argue that they spoil the look of the environment (probably the same folk that drive discoverys and shoguns round the city centre....)
fusion - the answer to huge power supplies, from a tiny powerstation, realtively cheaply (the running, not the building...). however potentially hugely catastrophic if it goes BOOM - and it still doesn't work... now cold fusion - that's a whole different kettle of fish....
hydrogen fuel cells - as developed by BP and Shell......no more oil required, just water, and away of ionising/electrolysing it to produce H+ ions.....clean, cheap and the end of oil - but........when will they actually release said technology? it'll be dribbled out for little uses here and there (already is...) and will avoid the obvious consumers - the drivers.....
