Before installing solar panels on your roof, check with your home owners association. Some associations have restrictions on what you are allowed to do to the outside of the property, and this might mean solar panels are not an option for you. It is better to have this information up front than to purchase the panels and be forced to remove them at a later time.
The best time to incorporate solar power into the design of a home or building is in the initial construction. Windows are best facing south to let maximum sunlight (hence greenhouse heat) in during the winter. Likewise, avoid windows facing directly into the summertime sun to keep things cooler, so less power is needed for fans or air conditioning. The maximum roof space, however, should always get sunlight exposure.
Rutgers ECE Senior Design ’14 The cost is $50 which includes an output transformer.