What is solar irradiance? Why does it matter?

Did you know we get better sun for solar energy than Florida?!

Part of our Solar Foundations Series aka Fun solar facts to know and share from SEG.

Solar irradiance often called solar resource is very important when it comes to planning a solar energy system for your home and business.

Because the Earth is round, the sun strikes the surface at different angles, ranging from 0° (just above the horizon) to 90° (directly overhead). When the sun’s rays are vertical, the Earth’s surface gets all the energy possible. The more slanted the sun’s rays are, the longer they travel through the atmosphere, becoming more scattered and diffuse.

In the summer the United States receives more hours of direct, high angle sunlight than in the winter. The summer days are longer and in places like the Southwest and parts of California very little sunlight is diffused by clouds, fog, pollution and other atmospheric and climate factors. 

If you take a deep look at the map above you will see we have a higher than normal solar resource in the Sierra Foohills even compared to the Sunshine State of Florida. 

When the sunlight is the best for solar energy, on highest and longest days of the summer, we have less, if any cloud cover.  Our dry summers account for that. Where as summers in the East and Midwest still receive rain when do do not. 

Therefore we have excellent solar resource aka solar irradiance in Nevada County and the surrounding area.

Lucky us!

This is what makes our solar proposals such a great deal  with short payback periods compared to other parts of the country. It’s because we get “better” sun!

Who gets the best sun for solar energy world wide?  See below!

Here is a little more food for thought to really see what is happening when it comes to solar irradiance.