Home » Solar Turbine » Illinois » Kewanee

Peak sun hours are a vital measurement to understand when considering the installation of solar panels. Peak sun hours are not the same as total sunlight hours because not every hour of sunlight during the day has enough strength and solar insolation to qualify as a peak sun hour. The rule of thumb is that a peak sun hour is when the intensity of the sun that is hitting your solar panel is providing at least 1,000 watts per square meter. This is an arbitrary number, but it is a number where most solar panels will be producing an efficient output and not underperforming due to sunshine that is not strong enough or direct enough.

If you’re using a fixed axis and fixed tilt solar panel, the ideal angle of the panel mount should be set at an angle equal to or close to the latitude of the location of the panel. Latitude is a valuable measurement to use when figuring how many daylight hours and the angle of the sun in the sky for your location. Since at locations with a higher latitude the sun will find itself at more variable angles in the sky throughout the year it is important to set the angle of the panel correctly and efficiently capture more peak sun hours. In the Northern Hemisphere the sun will be at lower angles in the Southern sky in the winter, and higher angles during the summer months, so the angle of the panel is crucial when trying to maximize output.

The sun moves through the sky during the day, and changes positions in the sky throughout the year as the seasons change. A fixed solar panel remains fixed in position during this movement. So, although it is effective in capturing sunlight, a 1-axis or 2-axis panel can be more efficient. A 1-axis panel tracks the sun's movement throughout the day from sunrise to sunset. In addition to that, the 2-axis panel also accounts for the movement throughout the year.

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

In Kewanee you can look at the average peak sun hours of a fixed solar panel mount, which will be 4.7 hours. This number iis an estimate based on data of previous years. With a tracking mount in Kewanee you could theoretically increase the amount of peak sun hours per with a 1-axis mount, and get 5.9 hours, or a 2-axis mount and potentially increase your average to 6.4 hours.