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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 La Harpe throughout the year can help you better estimate the amount of solar panels you will need to power your business or home.

If you open the newspaper in the morning or watch the weather channel on the news you can get an accurate prediction of sunrise and sunset each day for La Harpe. However, still knowing that the latitude of La Harpe is 40.6 can be a helpful number for your solar panel setup and planning. The closer your latitude is to zero the closer you are to the equator. At the equator you find the most consistent total sunlight hours throughout any given day of the year. As your latitude increases you can see larger discrepancies of daily sunlight hours during the year. For example, having very long summer days and very short and dark winter days

You will notice that the average peak sun hours for La Harpe change based on the type of panel being used. The reason for this is quite simple. A fixed panel does exactly what it sounds like, remains fixed in one position at all times. A 1-axis and 2-axis panels have axis that allow them to rotate. The 1-axis rotates with the sun's daily east to west movement while a 2-axis also adjusts for seasonal changes.

Weather is one of the major culprits that will cause inconsistent total peak sun hours for any given day. The sunrise and sunset will always be predictable every day, but the weather is hard to predict and cloud coverage can greatly diminish the efficiency of a solar power system on any given day. On the bright side, a location that is known to have cloudy weather a majority of the year could have unexpectedly more sunny days, so it can go both ways.

We can use previous years of data to estimate the amount of peak sun hours in La Harpe. A fixed tilt mount for example will receive 4.6 average hours per day. For more efficiency for your system in La Harpe you could use a 1-axis tracking mount and increase your daily peak sun average to 5.9 hours, or even further with a 2-axis panel to get an average of 6.1 hours.