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Peak sun hours is one of the most important criteria to examine when considering installing a solar power system. Peak sun hours are different than total sunlight hours in a day because the strength of the radiation of the sun varies throughout the day. For example, during sunrise and sunset the solar insolation from the sun is less powerful than at noon. For a moment of sunshine to be considered a peak sun hour the intensity needs to be at least 1 kilowatt per square meter. This means that a square meter of your solar panel should be receiving 1 kilowatt of energy from the sun. This number is used because it is an amount of light that allows a solar panel to produce output efficiently and not under perform due to lack of sunlight power.

The latitude of the location is important for measuring peak sun hours. The latitude determines how much overall sunlight there will be in a day. With a given latitude, time and date, one can accurately determine when sunrise and sunset will occur. Areas with latitudes closer to the equator will have a more consistent range of solar insolation throughout the year. Whereas areas closer to the poles will have a greater variance during the summer and winter months due to their higher latitudes.

You will notice the difference in peak sunlight hours depending on the panel type. The more flexibility the solar panel has the efficient it can be throughout the day and the year. A fixed solar panel remains in the same position at all times. A 1-axis panel follows the sun throughout the day as it moves through the sky and eventually sets. A 2-axis panel not only tracks the daily movement, but also adjusts based on the sun's changing position in the sky throughout the year as the seasons change.

Weather is a big determinate of average peak sun hours each day. There are many aspects of weather that can increase or lessen the peak sun hours in a day in a particular location. For example cloud coverage is a crucial variable. And more importantly, what type of cloud coverage; thin scattered clouds will have less diminishing power on the solar insolation than thick rainy storm clouds. Sometimes long periods of sunny days are rare in certain locations, this would increase average peak sun hours for that time-frame

Since we know the latitude of Bison we can take the average amount of total sunlight hours and estimate that with a fixed solar panel there would be an average of 5.4 peak sun hours per day. 6 hours per day with a 1-axis tracking mount that tracks the sun from sunrise to sunset, and 7.3 hours with a 2-axis tracking mount that tracks the sun everywhere in the sky.