PV cells were originally designed by NASA to provide power from the sun directly to astronauts in space. Since those early days, PV cells have changed significantly and are now capable of providing power on a residential and commercial scale. Panels and Modules are available in a wide variety of shapes and sizes and can even be integrated directly into building materials in some cases.
Traditional multicrystalline panels are firm and generally mounted on a pane of glass to ensure their integrity. Newer technology has introduced the concept of thin film photovoltaics, which are printed much like a poster in extremely thin strips. These are much more flexible and thus can be applied to just about any construction material including steel and plastic. Systems can be grid-tied and provide power directly to the utility or battery-backed to ensure power security in the advent of a storm.
The traditionally high cost of these systems has been a large part of the reason why they have not been more widely adopted by homeowners and commercial construction. With continued research and increased production, the cost of PV panels will continue to fall and will soon be a more evident solution in the renewable energy field.