My new series on getting greener in my Arizona home.
I have been thinking about this project for a few years now. My home in Arizona obviously gets real hot in the summer. With my summer electric bills coming in close to $300 a month and solar power systems available with no money down and low payments, it seemed like a good time to investigate greening up my home.
However, when you think about the issue that I have, creating solar power to run an AC unit is like treating the symptoms and not the cure. So let’s go backwards and see what the real culprit is.
Sun – Hot House – Electric – Air Conditioning – Cool House
You can see that the end goal here is to have a cool house. So what’s the root cause of why the house is not cool? It’s because of the Sun and its heat.
Yes, we all know that the Sun is hot, but how does that translate into making my house hot? Well heat is transferred in 3 different ways.
1 – Conduction – Simply put conduction is the transfer of heat through a solid object. If the outside edge of the brick on your house is hotter than the edge of the brick facing the inside. The heat will migrate from the outer edge of the brick to the inside edge.
2 – Convention – This is the heat transfer through the air. Imagine a hot piece of metal on the table. You put your hand close to the metal, but not touching it and you can feel the heat emanating from the metal. This is convention.
3 – Radiation – This is how the sun warms our planet. It’s electromagnetic waves travel through space. When the waves come in contact with an object, the waves transfer heat onto the object.
So below is a simple diagram of how these 3 methods of heat transfer work on your home.
My plan is to eliminate as much of the cause as possible before I tackle the symptoms. In this case I am planning to reduce the sun’s radiation heat onto my home’s roof as much as possible. I am planning on building another “roof” above my roof to block out the sun’s rays.