Energy Audit: First step in developing your energy plan

Dexter Coolidge, Northern New Mexico Group Conservation Chair, reports on his energy audit that he had completed prior to his investments in solar thermal and solar PV...

We have heard repeatedly that improving energy efficiency of our homes should be the first priority to save money on energy and reduce our carbon footprint: insulate properly, eliminate leaks, get curtains or thermal shades to cover our windows. The problem is, we don’t always know where the leaks are (if any), the insulation we have might be adequate, the cost of thermal shades seems prohibitive, and on and on. The solution to this problem, and really the best first step before you do any of those things, is to get a professional energy audit. While just a couple of years ago it was hard to find a qualified professional to do this, there are now a number of them and their charge, $300-350, is a fraction of the potential savings. Here is what you can expect with an energy audit:

• An examination of the home to find all the characteristics that will determine energy loss: total size, window and skylight size and insulation value, boiler and appliance efficiency.

• An examination of the outer walls and ceilings with an infrared camera to determine just where insulation may be missing or cold air leaking in.

• A blow door test, which reduces the air pressure in the house to
determine whether the leaks are resulting in excessive air turnover and
also to help identify more clearly just where the leaks are.

• A calculation of the estimated heat loss in BTUs from each element of the house, from slab to skylights (optional).

• An estimate of the cost of addressing each significant heat loss or electricity waste and the dollar savings to be expected from each.

A recent audit (in this case, of my house) provided the following surprises:

• A new boiler will save about $1,000 a year and cost $6,800, a payback of under six years. This was much better than I expected. New Energy Star boilers have greater efficiency at this elevation.

• Cold air was whipping in through improperly sealed electrical outlets. This took me about an hour and $5 to address. New thresholds under our doors will eliminate another source of cold air at a modest cost.

• A new Energy Star refrigerator will save about $100 a year in electricity.

• Installing Plexiglas under my skylights doesn’t make sense. The cost is substantial and only brings the R-rating of the skylights from 1 to 2. On the other hand, insulating the walls of the skylights to R-13 will save about $40 a year and cost only about $300.

• Installing thermal shades all over the house would cost a fortune and
might not make sense. However, the auditor recommended putting them where we sit frequently, keeping those areas comfortable while keeping the rest of the house at more moderate temperatures.

• The auditor also recommended (outside the scope of the audit) that we get a radon test and install a carbon monoxide monitor, both of which we have done.

There was one other bit of information of particular interest. About 45% of our heat is escaping through the slab, because it is not insulated. Nothing we can do about this, except build a new house! - Dexter Coolidge, NNM Conservation Chair

To get involved with our energy strategy, please contact Dexter Coolidge dextercoolidge@yahoo.com