Pole and ground mounts can take advantage of optimal placement, orientation, and angle.
Ground- or pole-mounted arrays may offer some advantages compared to roof-mounted systems, such as the ability to choose the best solar window, if the roof is shaded, and use the ideal orientation and tilt to maximize annual energy harvest—and the payout from available incentives. Production-based incentives (such as feed-in tariff programs), which pay a premium rate above retail for solar-produced energy, may influence your decision to go with a pole- or ground-mounted system, since increasing production by 5% to 10% over a 10- or 20-year power contract can add up to a significant payout. Pole-mounted arrays offer the additional advantage of easy seasonal tilt adjustment.
But these mounting options also present their own challenges, including expensive excavation and concrete. Trenches for conductor routing may require figuring out how to deal with existing structures, landscaping, concrete pads, underground sprinkler system locations, and buried utilities. (See “Ground Mounts for PV Arrays” in HP139, “Interrow Shading” in HP151, and “PV Array Siting & Mounting Considerations” in HP155).