How Weather Effects Solar Energy Production

Posted on: February 22, 2016

Temperature, air density, precipitation, pollution, fog, and wind can disturb solar energy production, but should not be considered ‘deciding factors’ when assessing your climate for solar power use. If these conditions are prominent in your geographic location, solar is still a viable option considering battery back-up can always get the job done in the absence of beloved sunny days. 

Sunshine Exposure for Solar Power

The length and strength of solar power received are the two most important factors in producing electricity through photovoltaics. As such, regions that receive the most sunshine per day will produce the most energy. Solar tracking can off-set the decrease in energy production when days become shorter and the sun is not at an ideal angle for maximum insolation.

Wind

Wind damage to your solar panels is unlikely considering they are specifically designed to withstand wind speed up to 80 mph or more. However, solar PV systems are subject to the same laws of physics as any other electrical circuit. The behavior of the electrical circuit in terms of voltage, resistance and current are governed by other effects, like air temperature and wind speed. Since wind speed influences air temperature, it is a piggy-back factor of how temperature can affect a solar PV system.

Temperature

Solar panel power production is the most efficient when temperatures are low in sunny environments.

  • High temperatures: Field and laboratory experiments (Rivers State University of Science and Technology at Port Harcourt, Nigeria in 2008) have revealed a drop of solar energy output for every increase in degree of a home photovoltaic solar panel once the panel reached 42 degrees Celsius, or about 107 degrees Fahrenheit.
  • Low temperatures: The angle of the sun determines irradiance (brightness) and insolation (strength of sun when it reaches ground) which both determine the amount of energy production photovoltaics. Locations closest to the poles, and/or during winter seasons, the angle of the sun is low and temperatures decrease, causing solar panel energy production to also decrease.

Air density

Thin air is ideal for solar power for the simple fact that when the air is thicker, it scatters more sunlight. Typically, the higher the elevation, the thinner the air is. Locations at or below sea level tend to have higher air density.

Snow / Rainfall

A thick layer of snow on your solar PV panels will affect the production of energy entirely. However, panels naturally give off heat and are purposely installed at an angle which will prevent the accumulation of thick layers of snow. During rain or snow, the length and strength of the sun is minimal and will decrease energy production as a result.

Pollution

Pollution, much like clouds or fog, diffuses sunlight so the strength of the of sun will decrease in highly polluted areas.

Cloud Cover / Fog

If you live in an area with dense cloud cover or fog, like San Diego, your solar power output will decrease but the solar PV panels will still produce electricity. Clouds/fog diffuse (spread out) sunlight, so the angle of the sun and/or panels are not as critical. The amount of solar energy produced in these conditions depends on the thickness and duration of the fog or cloud cover. A single cloudy day will not affect the amount of power coming into your home, it is more important on the amount of sun that your panels see on average per year.

Although weather can have a significant impact on solar power production, solar panels are built to withstand heavy rain, hail, wind and cycles of heat and cold for many years. Despite unfavorable conditions for solar power production, your home can still receive electricity it needs through battery back-ups and smart mounting solutions. Switching to solar is still a wise investment that will increase the value of your home, help the environment, and save you on energy bills. Call Action Air today to learn more about solar panel installation!