Photo-Voltaic
These systems use a process of converting sun energy into electricity. Efficiency and cost of this technology improved tremendously in the last decade. There are federal and state subsidies available for both commercial and residential installations. Most urban installations are tied to the grid and are designed to only partially offset electric use. The cheapest and best way to reduce your power bill is still changing your behavior.

Solar Thermal
The sun heats the water or a heat transfer fluid that transfers the heat to domestic hot water or a space heating system. Depending on configurations these systems can incorporate a variety of hot water storage tanks, heat exchangers, circulations pumps, controls and solar collectors.

Radiant Space Heat
The Ancient Romans and Koreans have used hydronic space heating for a very long time ago, but in modern building practice the technology has been mostly used in a form of boiler systems and radiators. Any hot water heating system can use solar arrays as a preheat, which makes retrofits simple and effective. With radiant floor systems heat distribution and efficiency is much higher and as opposed to hot air sustems there are fewer moving parts and less maintenance.

Solar Pool Heat
If you can afford a pool in the first place then you are probably smart with your money. Why not use a free source to heat your pool? Pool circulator pump runs the water through a solar heating collector, eliminating gas and electric heaters all together. Not only it can save you money in the long run, but it can make you feel better about your environmental footprint. And yes, pool party bragging rights are included with every system.