Home » Solar Turbine » Montana » Hathaway

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.

Knowing that the latitude of Hathaway is 46.3 can be helpful for understanding total sunlight hour variance. As you approach the equator latitude approaches zero. The closer the latitude is to zero, the more consistent the daily sunlight hours are throughout the year. Total sunlight hour consistency simply makes planning for your solar power needs easier, but it is certainly not a requirement.

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.

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.

For Hathaway the number of average daily peak sunlight hours for a fixed solar panel is 5 hours. If you are using a more efficient 1 or 2-axis panel then the number will increase to 6.4 hours for a 1-axis panel and 6.8 hours for a 2-axis panel.