OCTOBER 15, 2009 ISSUE
everGREEN Tips
Retrofit Logic
Energy is in the news a lot lately—energy news on how to save on utility bills, how to reduce our demands on natural resources, etc.
The greatest opportunity many of us have to contribute to a cleaner environment and a stronger economy may be hidden up in our attic, or down in the crawlspace, in our laundry room or kitchen.
Our home is a large and complicated energy consumer. There are many aspects to a home’s energy consumption: heating and cooling, hot water for domestic uses, lights and electronics, appliances such as refrigerators, dishwashers and the like.
As we all know by now, excessive fossil fuel consumption presents us with numerous downsides. It’s hard on our wallet, getting it out of the ground is risky work and can make a heck of a mess, it contributes to greenhouse gasses, increases our dependence on imported energy sources and sends our money out of our economy.
On the other hand energy “produced” by savings from insulating our attic is cheaper and cleaner than just about any source around.
I’d like to describe to you the general outlines of an energy audit and retrofit process that can help you get a better handle on where your home uses energy and how to begin the process of addressing it. One could envision it as three basic steps.
First, look for the ways your home is simply losing energy; second, look for ways to improve the efficiency of the energy-consuming appliances in your home; and third, look for opportunities to utilize renewable energy sources.
Whether it comes in over the grid from a Duke Energy power plant or in a tanker truck full of propane, we keep putting energy into our homes and it keeps doing work for us. It cleans the dishes, heats the water for our morning shower and keeps our houses toasty in the winter and cool in the summer—all good things.
Now, here comes the “but.”
Once this amazing stuff we call energy gets to our house, a lot of it—often as much as half of it—ends up getting wasted, lost or misused.
Imagine it is as if the driver backed up to fill your 500-gallon tank and said, “Okay, sir, I’ve got your tank half full now, and the rest I’m going to just dump in your driveway.” Would you say, “That’s fine, just be sure to bill me for the whole 500 gallons?” I don’t think so.
Yet in ways small and large, we lose energy throughout our homes and do not get the full benefit of what it is intended to do.
Homeowners can do their own energy audit process or hire a qualified professional. The U.S. Department of Energy offers a website, www.energysavers.gov, that can be helpful in getting started and I also recommend a book called the Homeowners Handbook to Energy Efficiency by Krigger and Dorsi. When looking for a professional I would recommend looking for someone certified through the nonprofit Building Performance Institute, also there is a trade group for home performance contractors called Efficiency First which maintains a listing by state.
In doing your own energy audit, you should look for several things. First, conduct a visual inspection for obvious problems, such as moisture or holes between the inside and the outside that may have been overlooked, or ductwork disconnected in the crawlspace (don’t laugh, it totally happens). A great deal of heating and cooling is also lost due to the “normal” amount of leakage that results from conventional installation practices as well as filters that aren’t changed, etc.
A professional building analyst will also use specialized diagnostic tools to evaluate how fast the air changes in your house due to leaks and where those leaks are. Many homes, for instance, have to heat an entirely new batch of air that has leaked in from outside about once every hour or two. No wonder that furnace keeps kicking on.
Ductwork leaks, wind blowing through walls and windows, poor or missing insulation in attics, walls and crawlspaces all allow heat to escape. These are system losses, call it waste, and it amounts to a lot of energy that you buy but don’t get any benefit from. It can be effectively addressed and substantially reduced, using conventional construction materials, an understanding of building science principles and serious attention to detail. Another book that will help the homeowner who wants to do it on his or her own is from Taunton Press by Bruce Harley and is titled Insulate and Weatherize.
Then there comes the topic that might be more accurately called “energy conversion efficiency.” Washing machines, dishwashers, light bulbs, refrigerators and other appliances convert energy in the form of electricity into work for us. The question is how efficient are they at the conversion of energy into work. For instance, everyone by now has seen the compact fluorescent bulbs. A CFL bulb using 23 watts produces the same light as a regular incandescent bulb using 100 watts. That is a lot more efficient. It’s like watching somebody peel potatoes and seeing that they skin it pretty thin, or do they cut too deep and throw away half of the potato with the skin. You start out with a big, five-pound bag, and end up at the supper table without enough mashed potatoes to go around, because of an inefficient process back in the kitchen. Not good. The Energy Star program rates the efficiency of major appliances, and that is a good place to start.
The third part of a total retrofit process is to consider renewable energy sources. In North Carolina, we have a source of pollution-free electricity that we can easily tap into, called N.C. Green Power. You merely call your electricity provider (BREMCO is a participant) and they will arrange for a portion of your electricity to come from power that is produced renewably, as verified by an independent, third-party program administrator. You choose how much you want to come from renewable resources by contributing an extra four cents per KWH. They ask you to purchase in blocks of 100 KWH per month which comes to $4. So, for instance, if your average monthly bill is 1,000 KWH, and if you wanted to be sure half your power was produced from renewable resources, you would purchase five blocks at $4 each. So, for $20 per month, you would have reduced your consumption from fossil fuel sources by 50 percent. That is hard to beat.
Another renewable approach that can save energy would be to install solar hot water heating for your domestic uses. This is pretty simple these days, and currently BREMCO is rolling out a $500 direct cash rebate that sweetens the existing state and federal tax incentives. The ASU energy center is also a great local resource as well as the N.C. Solar Center in Raleigh.
So there is the basic idea. Three steps. First, look for ways to stop wasting energy. Second, look for opportunities to increase the efficiency with which you use energy, and third, consider how to incorporate renewable energy sources into your home energy profile.
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