The angle of solar panel installation is one of the most commonly asked and searched questions by homeowners who are considering solar energy.
A quick search will fetch a long list of search results that purportedly help users figure out the best angle for installing their solar panels. Some of the more imaginative websites even offer geography-specific ideal angle for installation.
Why? Why do people care for the angle of their solar installations?
Power Generation Efficiency
The theory goes that solar panels produce energy at maximum efficiency when the sun’s rays fall on them directly, i.e., perpendicularly. The installation angle should ensure that the panels receive maximum sunlight, as the sun’s relative position changes through the day.
While the theory is sound, the reality is quite different. The tilt, or the angle of installation, has little (roughly 1% to 3%) effect on energy production efficiency. What’s really important is the orientation (direction) of the installation of the solar panels.
Solar Panel Orientation
The state of Connecticut is located well above the Tropic of Cancer. During the summer solstice, the sun is directly above the Tropic of Cancer, and during the winter solstice, it’s directly above the Tropic of Capricorn. Due to its location, Connecticut will never witness the sun exactly above it. Even at its highest point, during noon, the sun’s relative position will appear to be south when looking from Connecticut. That’s why, all solar panel installations across Connecticut must be pointing in a Southward direction.
The orientation of the solar panels is a far more critical factor than the tilt or angle of the installation. A 45o deviation from the south, i.e., East/West-facing solar installation, will cause a 30% reduction in the power generation efficiency of the solar panels.
What Else Matters?
We consider two more things when installing solar panels – surface angle and access to sunlight.
For rooftop installations, the surface angle is the roof’s angle. Many houses in Connecticut have a sloping roof at an angle of 30 to 40 degrees. This leaves little room for installers to maneuver.
At Green Power Energy, we try to strike the right balance between maximizing energy generation efficiency and aesthetics, so that homeowners get the best of both worlds.
The other factor, access to sunlight, is a more complicated problem. We recommend at least 80% shade-free access to sunlight for the solar panels. Trees, buildings, and other obstacles can prevent solar panels from receiving optimum sunlight during crucial hours. If that’s the case, we inspect the customer’s property and recommend the ideal location for installing their solar power system, so that their solar panels receive substantial sunlight.
Contact Green Power Energy for more information.