Shading Analysis

Shading is an important consideration, but some shading is allowable for near optimal performance
Ideally a solar installation will have full sun all day, but even a partially shaded location can produce close to the same yearly energy output.

Annual Shading - Most of the heat collected during the year occurs between April and September. If shading occurs during the winter months when the sun is low in the sky, only a small percent of the overall production will be lost. Another consideration is that deciduous trees lose their leaves in the fall. Approximately half of the solar radiation gets through a leafless tree.

Daily Shading - The lion’s share of the daily collected energy occurs between 10am and 3pm. If shading occurs in the morning or late afternoon, the system will still perform quite well. Additional collector area can overcome losses due to partial shading.

Tools - There are shading analysis tools available to very accurately calculate the percent of full sunlight for the location. An example is the Solar Panthfinder. A solar professional should have such a tool to determine the solar resources available.