Efficiency Of A Solar Heating Panel

The solar energy factor is defined as the energy delivered by the system divided by the electrical or gas energy put into the system.

Efficiency of a solar heating panel.

Solar energy factors range from 1 0 to 11. It may seem counter intuitive but solar panel efficiency is affected negatively by temperature increases. The average efficiency of solar panels falls between the 17 to 19 percent efficiency range. If a solar panel has 20 percent efficiency that means it s capable of converting 20 percent of the sunshine hitting it into electricity.

High quality solar panels can exceed 22 efficiency in some cases and almost reach 23 but the majority of photovoltaic panels available are not above 20 efficiency. Photovoltaic modules are tested at a temperature of 25 degrees c stc about 77 degrees f and depending on their installed location heat can reduce output efficiency by 10 25. Use the solar energy factor sef and solar fraction sf to determine a solar water heater s energy efficiency. As the temperature of the solar panel increases its output current increases exponentially while the voltage output is reduced linearly.

Most solar panels are between 15 and 20 efficient with outliers on either side of the range. The higher the number the more energy efficient. The efficiency and effectiveness of a solar water heating system will depend on the size and type of panels used and on positioning them to maximise absorption of solar radiation. The higher the value the more energy efficient the system.