How to assess shading impact on my solar setup?

Understanding Shading Types and Effects

Shading can be categorized into three main types: intermittent, continuous, and seasonal. Intermittent shading occurs when the sun is partially blocked by trees or structures, while continuous shading is caused by a permanent object like a building or a tower. Seasonal shading changes as the sun’s path moves throughout the year.

To assess the impact of shading, consider the angle of incidence and the duration of shading. A 10% reduction in energy production can be expected for intermittent shading that lasts for 1-2 hours per day, while continuous shading can reduce energy production by as much as 50% or more. To mitigate the effects of intermittent shading, consider adjusting the solar panel layout or installing microinverters or power optimizers.

Using Online Tools and Software

Online tools like PVWatts and Solar PathFinder can help assess the shading impact on your solar setup. These tools use the National Renewable Energy Laboratory’s (NREL) PVWatts model to simulate the performance of solar panels under different shading conditions. To get accurate results, enter your solar panel’s specifications, the system’s tilt and azimuth angles, and the shading data for your location. The tools will provide an estimate of energy production and help you identify areas where shading is most significant.

On-Site Shading Assessment

Conducting an on-site shading assessment is essential for determining the impact of shading on your solar setup. Measure the time of day and duration of shading using a solar path diagram or by observing the shadow’s movement. Take note of any obstacles like trees, buildings, or power lines that may be causing shading. Record your observations and use this data to adjust your solar panel layout or to inform your decision-making when selecting a new solar panel system.