If you know that you cannot reach your solar panels to clean them, the best thing to do would be to hire a professional to clean it for you. if you are not sure of who to call, you should ask the company that came and installed the panels for you.
Carefully consider the types of solar panels you plan on having installed. Long ago, if you didn't have enough roof space, you'd need very expensive high efficiency mono-crystalline panels. There are now more advanced polycrystalline panels and even thin film panels. If you've got enough roof space, you might wish to look at the size of the panels in relation to their output capacity to avoid having insufficient panels that you need more of later.
Don't waste your time lining the solar panels beneath an array of florescent lights--though it may sound tempting. Solar cells are not designed to generate a voltage from fluorescent light sources and this is a waste of energy of time. Any spot in the yard would be a better location for the panels.
Hot Sun Industries, maker of the Powerstrip solar pool heating system explains basic system operation as well as some plumbing guidelines.
Keep your solar panels out of the shade. It might seem obvious, but your solar panels do need sun. Make sure that you are not installing them in the shade. Trim back the branches on surrounding trees if you need to. Failing to do so could cost you more than half your energy output.