Solar Power Structures
The only requirement to create power from the sun, is for the solar panels to receive light from the sun. The closer that light is to a right angle (90 degrees) to the panel, the higher the amount of electricity that the solar panel is able to create.
The most desirable would be to have a system that tracks the sun's movement, keeping the sun's rays at a 90 degree angle for as much of the time as possible. Recent developments with the semi-conductor materials used in Photovoltaics (PV) have reduced the need to be always at a 90 degree angle, achieving fairly strong electrical current at angles less than 90 degrees, thereby eliminating the need for high cost and high maintenance tracking systems on your solar panels.
In the northern hemisphere, solar radiation is maximized over the summer, between spring equinox and fall equinox. It is at it's lowest at the Winter solstice. Therefore, it is best if the permanent structure housing your solar panels angles the panels to have the best angle at the equinoxes. This maximizes performance all year around. For example, if the panels were set to maximize at the summer solstice, then their performance in the winter would be atrocious as the sun drops significantly lower in the winter, and vice versa.
Using the above as your guidelines, you can pretty much put solar panels anywhere - on the ground, on your roof, on a wall structure, overhead to provide shade in a parking lot, on a post to provide electricity to a parking meter, on a cliff or a mountainside. In fact there was a winery near the bay area who mounted their solar system (quite a large one) on a small lake on their property on floatation devices. This kept the solar panels cool thereby increasing their performance, and at the same time freed up enough land to produce an additional $150,000 in bottled wine from the grapes that were planted in the space that would have been used for the solar panels. Over the life of the solar panels (~25 years guaranteed), that is a significant sum (do the math!!).
So basically, you can be as creative as you want, and as much as your budget allows! The All About Solar Team, is very experienced in all types of construction, and can work with you to find the best solution for your needs and your architectural tastes.