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The average peak sun hours of Saint Johns is a crucial measurable component needed to efficiently implement a solar power system in a home or business. Put simply, peak sun hours are the hours of sunlight a day that are strong enough to be efficiently absorbed by solar panels and eventually turned into usable electricity. Not every minute of sunlight during a day is strong enough to be useful to a solar power system. Think about just minutes after the sunrises, which officially counts towards total hours of sunlight, but is usually too weak to be counted in peak sun hours because the strength of the solar insolation is not strong enough near the horizon to be absorbed and turned into electricity at an efficient rate. Times during the day like this, where the sun is out but not strong enough, are not counted as peak sun hours. In other words, the amount of peak sun hours in a location will theoretically always be less than total sunlight hours for a given day.

Sunlight hits the earth directly at the equator. This is why the equator has a latitude of zero degrees. The latitude of Saint Johns is 38.0. Knowing the latitude of Saint Johns can help you plan for your solar panel setup, as the larger the latitude the more variance you will see throughout the year for total daily sunlight hours.

You will notice that the average peak sun hours for Saint Johns 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.

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.

We can use previous years of data to estimate the amount of peak sun hours in Saint Johns. A fixed tilt mount for example will receive 4.7 average hours per day. For more efficiency for your system in Saint Johns you could use a 1-axis tracking mount and increase your daily peak sun average to 5.6 hours, or even further with a 2-axis panel to get an average of 6.4 hours.