Franklin Solar Power Information & Peak Sun Hours
Solar Green Energy Summary for Franklin, Tennessee
Lattitude: 35.9215
Sunlight
Fixed Tilt Sunlight Hours: 5 hours per day
1-Axis Tilt Sunlight Hours: 6.1 hours per day
2-Axis Tilt Sunlight Hours: 6.2 hours per day
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.
The equator has a latitude of zero while Franklin has a latitude of 35.9. Any city located on the equator will receive the most sunlight throughout the year because the sunlight arrives at a perpendicular 90 degree angle to the earth at the equator. The further you are from the equator the more your daily sunlight hours can vary.
You will notice that the average peak sun hours for Franklin 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.
There are more variables than latitude that can change average peak sun hours. Weather patterns and geography will influence solar insolation that reaches your system. Thick grey storm clouds for example will block out a lot of the sun to the point where there may be no peak sun hours in the middle of the day when the sun is usually very powerful. Trees and mountains can deflect the sunlight, so be sure your solar panel is selectively placed.
We can use previous years of data to estimate the amount of peak sun hours in Franklin. A fixed tilt mount for example will receive 5 average hours per day. For more efficiency for your system in Franklin you could use a 1-axis tracking mount and increase your daily peak sun average to 6.1 hours, or even further with a 2-axis panel to get an average of 6.2 hours.