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The average amount of peak sun hours in a day is a different and more useful number as it relates to solar panels than total sun hours. Total sun hours are exactly what you would expect; the total amount of hours that the sun is out during a 24 hour period. Peak sun hours, on the other hand, are the total number of hours in a day where the sunshine is strong enough to to be absorbed and used by solar panels. Sunlight early in the morning or late at night is often not strong enough to count toward peak sun hours. Because of this, total sun hours will always be more than peak sun hours. Looking at the average peak sun hours in Marshall throughout the year can help you better estimate the amount of solar panels you will need to power your business or home.

Although you can easily predict sunrise and sunset hours each day to the minute, looking at latitude can help with your solar planning. The closer you get to the equator the closer your latitude gets to zero. Sunlight hours on the equator are consistent throughout the entire year. Places further from the equator can have large variance in daily sunlight. For example higher latitudes can have very long summer days with lots of sunlight and very dark winters. The latitude of Marshall is 39.4.

There are a few ways to increase average peak sun hours per year for your solar power system. One way is to use a tracking mount solar panel instead of a fixed tilt solar panel. A 1-axis mount will track the sun throughout the sky from sunrise to sunset, giving your panel a more efficient facing direction towards the sun throughout the day. A 2-axis solar panel will track the sun in the sky throughout the day, but also change and follow the angle of the sun in the sky throughout the year. Both of these axis system solar panels will produce higher average peak sun hours than a fixed solar panel.

There are more variables than latitude that can change average peak sun hours. Weather patterns and geography will influence solar insolation that reaches your system. Thick grey storm clouds for example will block out a lot of the sun to the point where there may be no peak sun hours in the middle of the day when the sun is usually very powerful. Trees and mountains can deflect the sunlight, so be sure your solar panel is selectively placed.

Since we know the latitude of Marshall we can take the average amount of total sunlight hours and estimate that with a fixed solar panel there would be an average of 4.9 peak sun hours per day. 5.6 hours per day with a 1-axis tracking mount that tracks the sun from sunrise to sunset, and 6.3 hours with a 2-axis tracking mount that tracks the sun everywhere in the sky.