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The amount of hours from sunrise to sunset is equal to the total sunlight hours in a 24 hour period. Similarly, peak sun hours are the amount of total sunlight hours in a 24 hour period that are strong enough to provide power from being captured by a solar panel. Not every hour of sunlight delivers the same amount of energy resources. The sunlight at sunrise does not provide as many resources as the amount of sunlight mid-day. Thus, looking at the average peak sunlight hours for Index is valuable for calculating your solar needs.

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 Index is 47.8.

Depending on your output needs, to get more out of your solar panels you can either upgrade your technology, buy more panels, or buy different tracking type panels. A fixed solar panel remains fixed at one angle throughout the year. A 1-axis panel will produce more output because it follows the path of the sun from sunrise to sunset to maximize sun exposure. Even more productive is a 2-axis panel that not only follows the sun's path throughout the day, but also accounts for the more subtle sun changes throughout the year with the different seasons.

The sunrise and sunset is very predictable every day, but things like cloud coverage and weather are less predictable and vary daily and annually. If a location that is usually very sunny experiences a huge increase in storms and cloud coverage in a given year than the average peak sun hours for that day or year will probably decrease. Tall objects such as trees and buildings can block out the sun during high solar insolation times, so be sure to strategically place your solar panels to get better efficiency.

For Index the number of average daily peak sunlight hours for a fixed solar panel is 4.4 hours. If you are using a more efficient 1 or 2-axis panel then the number will increase to 5.5 hours for a 1-axis panel and 6 hours for a 2-axis panel.