How to know if wall or roof faces true south

How close to true south is the wall or roof on which you would like to mount your solar panels? There is a very simple way to find out. All you need is a watch, a pencil, a sunny day, and a protractor, which can be made by pasting the accompanying diagram on a piece of cardboard. Now follow these steps:

* Take the protractor and place it up against a window in the wall in question.

* Find out from a local weather station the times of sunrise and sunset in your region. Solar noon occurs exactly midway between these two times.

* At solar noon, hold a pencil vertically at the center of the flat side of the protractor. The fall of the pencil's shadow will indicate the number of degrees off true south your collectors would be. Thirty degrees off true south will still provide 90 percent solar efficiency. At 45 degrees, efficiency is only 72 percent.

Another way of finding true south is to go outdoors at solar noon and stand at the end of the shadow cast by a telephone pole (the pole must stand straight up and not lean to one side). Now turn directly toward the pole and you will be facing true south.

About these ads
Sponsored Content by LockerDome

We want to hear, did we miss an angle we should have covered? Should we come back to this topic? Or just give us a rating for this story. We want to hear from you.

Loading...

Loading...

Loading...

Save for later

Save
Cancel

Saved ( of items)

This item has been saved to read later from any device.
Access saved items through your user name at the top of the page.

View Saved Items

OK

Failed to save

You reached the limit of 20 saved items.
Please visit following link to manage you saved items.

View Saved Items

OK

Failed to save

You have already saved this item.

View Saved Items

OK