How does snow affect the performance of solar panel power? It’s not uncommon to get heavy snows in the Virginia/Maryland/DC areas, and sometimes it can cover the ground for two weeks of the year. Some important implications to consider are how snow affects solar power system structures, sunlight availability, and what benefits snow can have on a solar system.
The biggest concern is that the weight of snow will have adverse impacts on solar panels or their racking system. Fortunately, solar panels, and their racking systems are designed to withstand heavy accumulations of snow; much more than they are expected to endure in real-life scenarios. This is especially true for twin-rail racking systems which have supports that are optimally placed for minimizing module deflection (sag in the middle of the panel).
Another worry is that snow will eliminate a solar system’s access to sunlight. While the ground may be covered with snow for a couple weeks a year, this unlikely to happen to a solar system for three reasons:
- solar modules are slick
- they normally sit at an incline, and
- they are placed in areas with exceptional sunlight exposure.
These things help to ensure that any snow that accumulates on solar panels will not be there for very long, and even when accumulation is present, solar modules will still have limited production because snow scatters sunlight rather than completely reflecting it.
While most of the discussion revolves around the concerns snow has on solar panels, there are actually benefits as well:
Cold Weather Benefits
The first is that snow goes hand-in-hand with cold weather, which is when solar panels, like most other electronics, perform their best.
Dirt & Debris
The second is that dirt and debris adheres to snow, leaving solar panels cleaner once the snow melts away.
Solar panels shed snow even faster than a regular roof surface.
The last is that reflection from nearby snow can actually increase the amount of sunlight getting to a solar system, which is especially true for ground mount systems.