Energy From Sun.
Have you ever wondered why it gets so HOT in the roof space on a sunny day?
Well there is a lot of Energy coming from the Sun . . . .approximately 1.37 kw /m2 shines on the Earth
By the time the solar energy gets through the atmosphere to the ground it’s about 1kw/m2 for a flat surface square on to the Sun.
Even in Melbourne on an average day the typical 200m2 house will get around 8ookw hours of heat radiation onto the roof. In January it can be almost twice as much!
Some interesting Solar Exposure Maps, like this one, are available on the Bureau of Meteorology website at this link: Solar Exposure, if you want to check the solar radiation for your location.
This shows the solar energy received in Mega Joules (MJ) on a horizontal surface. (to convert MJ to kwh multiply by 0.28).
The maps are based on measured values so they includes things like times of cloud cover.
If you follow the above link you will be able to find a map of values for each month.
See Sustainability for more posts.