Equivalent hours of full sun, that’s the term made up by engineers to aid in forecasting the output of a solar electric array or perhaps a more technical term equivalent full sun hour.
To get a full sun hour you need the sun to be dead center at noon, the day has to be clear directly overhead. Since the sun moves, or I mean the earth moves, it’s never as intense as it is at noon. If you add up all the solar radiation that a surface receives between sunrise and sunset, we can come up with the figures of total solar radiation per day. You need to divide that total amount by the energy in a full sun hour to equal the equivalent hours of full sun for a day.
You can normally find these figures for each day of the month, and then the average equivalent hours of full sun in forms for system designers.
An equivalent full sun hours is determined as the amount of solar energy that strikes a horizontal surface that’s 1 square meter in area, at solar noon, in one hour, at sea level, on a clear day. That’s a lot of factors, right? wait, not yet, plus an air mass equal to 1.5. That normally equal 1000W (1kW) per sq. meter or 317 Btu/sq. ft. All this data for equivalent full sun hours are available for daily, month, and yearly basis. It let’s us know how much solar energy is there at any location.
The solar potential varies with location
I know this is an obvious remark for some people, but I rather inform anyone that does not know this. Some locations have more solar energy available to them than others, it all depends where you are. If you’re in the U.S you’ll find that the northwest areas get less energy than the southwest.
note: Just because the highest incidence of solar radiation is in areas like the southwest it doesn’t mean that solar energy systems are feasible on the northwest areas.
Measuring the available energy to you
You’ll find that most people jump into building solar panels before figuring this out. It’s not recommended because you might not use your solar panels and the solar energy from the sun to its full potential. I’ve discovered that to get the most of solar systems you need to study well your area and figure out where is the most feasible location to place your solar energy collectors.
The best way to that is to get a guide to help you get the best of each of the solar panels potential.