Jaffrey Solar Power Information & Peak Sun Hours
Solar Green Energy Summary for Jaffrey, New Hampshire
Lattitude: 42.8125
Sunlight
Fixed Tilt Sunlight Hours: 4.6 hours per day
1-Axis Tilt Sunlight Hours: 5 hours per day
2-Axis Tilt Sunlight Hours: 5.9 hours per day
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.
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 Jaffrey is 42.8.
Throughout the day the sun obviously moves throughout the Jaffrey sky. The suns position in the sky also changes throughout the year with the seasons. A fixed solar panel does not accommodate for these changes. However, a 1-axis panel rotates and follows the sun’s path during the day. A 2-axis panel both follows the sun’s daily path as well as the seasonal differences
Another reason to consider average peak sun hours is because weather can dramatically affect the day-to-day output of solar panels. It goes without saying that a dark stormy day will produce less output than a clear sunny day. Looking at a yearly average helps account for these daily variables.
Since we know the latitude of Jaffrey we can take the average amount of total sunlight hours and estimate that with a fixed solar panel there would be an average of 4.6 peak sun hours per day. 5 hours per day with a 1-axis tracking mount that tracks the sun from sunrise to sunset, and 5.9 hours with a 2-axis tracking mount that tracks the sun everywhere in the sky.