Can elevation impact solar panel efficiency?

Atmospheric Effects

At higher elevations, the atmospheric pressure decreases, resulting in lower air density. This reduction in density allows more direct sunlight to reach the solar panels, increasing the amount of irradiance they receive. However, the thinner atmosphere also means less scattering of shorter wavelengths, which can lead to a slight decrease in efficiency for crystalline silicon solar panels. For example, at 5,000 feet (1,524 meters), the air pressure is about 85% of sea level pressure, but the decrease in efficiency is typically less than 1%.

Temperature and Cooling Benefits

One of the primary benefits of elevated locations is the lower temperatures, which can improve solar panel efficiency. At higher elevations, the temperature difference between day and night is greater, resulting in a lower average temperature. This temperature difference can be used to advantage with cooling systems, such as evaporative cooling or misting systems, to maintain optimal temperatures and improve efficiency. For instance, a study in the mountains of Colorado found that temperatures were 5-10°C (9-18°F) lower than in the valley below, resulting in a 5% increase in solar panel efficiency.

Maximizing Efficiency at Elevation

To maximize efficiency at elevated locations, it’s essential to consider the specific conditions and choose the right equipment. This may include using higher-efficiency solar panels, such as PERC or bifacial panels, which can take advantage of the increased irradiance and temperature differences. Additionally, selecting a suitable mounting system and tracking mechanism can help to maximize energy production. For example, a south-facing slope or a tracker that follows the sun’s path can increase energy production by up to 20%.