Where Does our Energy Come From? (Part 1 Home Energy)
This topic may seem completely unrelated to gardening and permaculture, and I will admit it does have a very loose connection to gardening, but it is vital to permaculture. Permaculture starts in zone 0 which is your home. If your home is consuming more energy than is necessary: than we might look to figure out how to make our homes more in line with permaculture principles of sustainability.
One business ago I was a building analyst, energy auditor, and weatherization contractor, so I know buildings when it comes to efficiency. I went to school at Penn College in Williamsport, PA, and Portland Maine to learn the trade. There are a lot of misconceptions, and misinformation in the home energy space. I heard them all as a consultant and contractor, but with my diagnostic equipment I was able to prove not only what worked and what didn’t but often times by how much. Since the gardening season is winding down, I thought winter would be a good time to start thinking about permaculture in your zone 0. Throughout the home energy series I will give away all the secrets I learned as an energy auditor.
Before we even get into the specifics of how to improve the efficiency of your home and be more in line with permaculture principles, I think it is important to understand where the energy we use in our homes comes from now, how we use it, and even a little history to offer some perspective. Unfortunately, many people think it comes from a plug in the wall.
First a little history. Before the industrial revolution, wood fire provided the heat and cooking for homes. The artificial light was provided with candles or gas and oil lamps. In the early 1880’s, Thomas Edison invented the incandescent bulb, and built the first power plant. By 1908, 8% of American homes had electricity, and by 1925 that number rose to 53%. In the 1930’s, natural gas began to compete with wood and coal as a heating fuel. 
Over the past 60 years, Americans have embraced air conditioning, replacing earlier attempts at low-energy cooling. Evaporative coolers appeared in the 1920’s followed by window air conditioners in the 40’s. Central air followed in the 1950’s. Today at least 70% of existing homes and 80% of new homes have air conditioning. 
Apart from our heating and cooling needs, we also consume quite a bit of energy through our use of water heaters, televisions, stereos, computers, swimming pools, spas, and all types of electric gadgets. This makes the American household among the most energy consumptive in the world. 
As you can see from the chart below, today the majority of our electricity is generated by coal, followed by nuclear, with natural gas not too far behind. Natural gas is our major source of home heating, followed by petroleum. None of those major sources is sustainable or renewable, including nuclear. That is a great reason to rely as little on those sources as possible.
source: U.S. Energy Information Administration / Annual Energy Review 2010
Now that we know where our energy comes from, it is also important to know how we use it. If you know where your energy is being used, it is easier to focus your resources on the high energy draws first. As you will notice from the charts below that if you live in a cool climate, you really need to focus on making the heating of your home more efficient, while in a warm climate air conditioning is more important.
1. Krigger, John., Dorsi, Chris., “Residential Energy,” April 2004.