You can use a small windmill and a generator. Or a window 2 catch the suncells. But if u want 2 start from bottom..wit nothing!..then im blank!

Using water wud work, bit of a bulky system tho. And a solar cell would be expensive. Heat is the way 2 go tho.

hmm .. I see the question was directed at sid? bah - ill answer anyway :p .. .. I have no idea how much these ideas would produce, but feel free to edit/improve them as you wish .. You could use your water supply to power a turbine, which generates power via a dynamo (or similar device) -- try things like your drainpipe, water-tank, or even try your toilet (the cystern - the square box thing) .. ?

btw - it is very unlikely to get any 'profit' from using solar panels within less than 2 years (unless you have VERY large amounts of sunlight) due to the very high investment cost, and produce the amount of engery you are needing .. ..