Saturday, November 3, 2007

energy audit



A couple of weeks ago, we had an energy audit of our house. We've been wanting one since we bought our house three years ago, but it's taken us a while to find somebody that we thought was objective enough to provide us just with the service of the audit.

The Association for Energy Affordability (AEANYC) charges $350 for an energy audit, and they do provide a report afterwards that gives you estimated cost of work. If you move forward with any of their suggestions, they will provide the contractors and also follow-up afterwards to monitor the various numbers.

The AEANYC also has programs for low-income families, to help the homeowner get a maximum amount of money back from the government to compensate for energy efficient changes made to the home and also to finance changes in a low-rate loan. We do not fit in that category, but AEANYC will still help us with rebates that are due to us, should we make changes.

This entry's photo shows the contraption that was placed on our door for a blower door test, which measures how much heating and cooling escape through unseen cracks and gaps in doors, windows, etc. When the blower door fan is turned on, the house gets very cool and drafty. We could even feel drafts when we placed our hands over electrical outlets!

Our house is 100 years old, so we had quite a few drafts. Our house also has no insulation. Ed installed fluorescent bulbs when we moved in, so that was already done. Other changes that were recommended to us in the report (received 2 weeks later) include low flow water devices, a CO detector directly above our stove (our only current one is linked to our fire and alarm system), a digital thermostat, and a new boiler.

AEANYC likes to look at energy audits as processes, not as a series of stand-alone factors. For example, the auditor asked us if temperature control in our basement and attic mattered to us. (It doesn't.)This allows for the creation of "zones" that need to be heated and cooled efficiently and those that are less of a priority.

Making some of these changes will pay themselves off in 10 years, and some will take longer. (Low flow water devices would have a quick payoff for us, for example; they're inexpensive and would save water costs immediately.) Some increase the value of the home, and some don't. (Insulation would increase the value of our home.) Some just would make things a lot more comfortable. ("Heated Area Infiltration Reduction 1" would make cold days more bearable.) These are the factors that we're going to think about when we meet with AEANYC in the next couple of weeks to move forward.

It was nice to get actual numbers behind some of our actualities and where we should be. Getting back to the blower door test (easily the sexiest part of the audit): Our house had a reading of 4800 CFM50, and AEANYC would like to lower that to 2800 CFM50. The current industry standard is 1030.98 CFM50. [The CFM50 is explained here.] (It should be noted that they measured every room in the blower door test, but the report gives us one total number.)

The recommendation we received is for $21,968 in work, which has a simple annual payback of 18.6 years. $10K of this is to replace our 1968 model boiler, which could be more efficient but isn't quite inefficient. (In other words, improvement would be marginal, so this increases the payback period significantly while emptying our wallets quickly.) I don't see a new boiler in our immediate future, but I am fantasizing about insulation and "Heated Area Infiltration Reduction."

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