Washington Solar Power Information & Peak Sun Hours
Solar Green Energy Summary for Washington, West Virginia
Fixed Tilt Sunlight Hours: 4.2 hours per day
1-Axis Tilt Sunlight Hours: 5.6 hours per day
2-Axis Tilt Sunlight Hours: 5.9 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 Washington has a latitude of 39.2. 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.
Depending on your output needs, to get more out of your solar panels you can either upgrade your technology, buy more panels, or buy different tracking type panels. A fixed solar panel remains fixed at one angle throughout the year. A 1-axis panel will produce more output because it follows the path of the sun from sunrise to sunset to maximize sun exposure. Even more productive is a 2-axis panel that not only follows the sun's path throughout the day, but also accounts for the more subtle sun changes throughout the year with the different seasons.
The sunrise and sunset is very predictable every day, but things like cloud coverage and weather are less predictable and vary daily and annually. If a location that is usually very sunny experiences a huge increase in storms and cloud coverage in a given year than the average peak sun hours for that day or year will probably decrease. Tall objects such as trees and buildings can block out the sun during high solar insolation times, so be sure to strategically place your solar panels to get better efficiency.
Since we know the latitude of Washington we can take the average amount of total sunlight hours and estimate that with a fixed solar panel there would be an average of 4.2 peak sun hours per day. 5.6 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.