How to calculate kWh

How to calculate kWh

You can calculate the energy produced by your panels per day using a simple formula:

• Size (in square metres) x 1,000

So, for example, our smallest solar panel is 1.94m.

1.85 x 1000 = 1,850

• Take this figure and multiply it by the efficiency rating of your panel as a decimal.

So that same solar panel has an energy rating of 19.73%

Therefore:

1,850 x .1973 = 365

• Now you multiply this figure by the number of sun hours per day, and then divide by 1000.

In Darlington, there are approximately 17 hours of sunlight at the height of summer. During the darkest part of winter, there are just over 7 hours of daylight.

So during the summer solstice:

365 x 17 = 6,205 ÷ 1000 = 6.21 kWh per day

And during the winter solstice:

365 x 7 = 2,555 ÷ 1000 = 2.56 kWh per day

As these figures vary from month to month, you can get an average of daylight hours and then multiply them by 30 for a monthly average.