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Does a Solar Panel Stop Working When It Gets Too Cold?

Although a solar panel produces less electricity in the winter than in summer, it's not due to the cold. In fact, the silicon material that makes up the active part of a solar panel works better at low temperatures than when it's hot. However, sunlight is less direct in cold months, resulting in a lower solar panel output.

Description
- A solar panel consists of many individual cells, all wired together in a grid that collects and combines the output of each. The cells are made of silicon and traces of boron, arsenic and other elements. Light from the sun and other sources moves electric charges in the silicon at about 0.6 volts. Because the cells are electrically connected, their combined output is typically between 6 and 24 volts, depending on the design.
Temperature and Efficiency
- Most commercially-available silicon photovoltaic cells have a working temperature range from -40 degrees Celsius (-40 degrees Fahrenheit) to 85 degrees Celsius (185 degrees Fahrenheit). Because of the atomic structure of silicon and other substances used in solar cells, efficiency is highest at low temperatures and decreases as the solar panel warms up. If the same amount of light falls on a cold panel and a hot one, the cold panel produces more energy. In an experiment published by Renewable Energy UK, the output of a small panel that produces 750 milliwatts at 30 degrees Celsius (86 degrees Fahrenheit) drops to 450 milliwatts at 75 degrees Celsius (167 degrees Fahrenheit) -- a 40 percent reduction in power.
Angle of Sunlight
- Summer months are hot because the sun's rays hit the Earth's surface more directly. In winter, the sun is lower in the sky, dispersing less energy. Weaker sunlight and shorter daylight hours means a solar panel produces less energy in a 24-hour period, even though lower temperatures increase its efficiency.
Air Mass
- A solar panel has the highest efficiency in space because no air exists to scatter the energy in sunlight. In the vacuum of space, sunlight carries 1,300 watts of energy per square meter. By the time it reaches the ground on Earth, the energy is reduced to 1,000 watts. When the sun is high overhead in summer months, its rays are more direct and they take the shortest path through the atmosphere to the ground. In winter, sunlight travels a longer distance through the air because the angle is lower. The additional scattering of sunlight in winter months reduces its intensity further, so less of the sun's energy is available to a solar panel during this time.

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