Deirdre and her numbers

Posted Wednesday, February 27, 2013 in Sustainable Maine

Deirdre and her numbers

A thermal image of a house shows where the leaks are coming from. 

by Paul Kando

It is a beautiful Maine farm house. Deirdre and Mark (not their real names) had an energy audit done on it back in 2007. When I ran into her the other day, I asked about their progress in home weatherization. They didn’t do anything. Mark said they could not afford to. Now Mark is gone, there was a divorce, and Deirdre asked for a copy of the audit report. I sent it along with some back of the envelope calculations.

Looking back over more than three hundred home energy audits, Deirdre’s farm house consumes just about the average amount of oil for Midcoast Maine houses, 1,079 gallons per year. At the time of their audit, at $2.70 per gallon, their annual fuel bill came to $ 2,913. Had they acted on the recommendations in their energy audit report, Deidre and Mark would have reduced their oil consumption by 55 percent, (again the average for our area), reducing their annual fuel bill by $1,602 the first year, $1,714 the second year, $1,834 the third year and so on, for a total savings of  $13,843 since the time of that audit. They could have spent this amount on weatherization, recovering all of it from energy savings by now. Mark could not afford it, yet spent nearly twice that much on oil anyway. To add insult to injury, Deirdre is now stuck with a heftier fuel bill this winter -- the price on her last bill, $3.75 per gallon, translates to a $4,046 for the year. 

What’s done is done, but all is not lost, Going forward, Deirdre can still reduce her oil consumption by 55 percent, from 1,079 to 486 gallons and her fuel bill to $1,823 by acting on the original energy audit report’s recommendations. That’s an annual saving of $2,223 in one year. In the unlikely event of the price of fuel oil holding  steady, her cumulative cost savings will come to $6,669 over 3 years, $11,115 over 5 years, $15,561 over 7 years and so on. In other words, she can spend over $15,000 on energy improvements now, recover her investment in 7 years, and enjoy reduced fuel bills forever after.

According to a University of Maine forecast, our 2018 energy bills will eat up 40 percent of the average Maine family budget, up from 20 percent in 2008 and 5 percent in 1998.  Indeed, while oil prices do fluctuate short term, they have been rising at a rate of about 7 percent per year over the long haul, according to the Energy Information Administration --  and Deirdre and Mark’s heating costs since 2007.  Not acting, she can expect her annual heating bill to rise from $4,046 to above $12,000 in 7 years – a scary prospect indeed. The good news is that her projected 55 percent cumulative energy cost savings will increase  as well, to $18,673. Should she spend this amount for energy improvements, she will break even in 7 years.

“We don’t have $18,000 to spend”, Mark might say, but Deirdre would be better off making a plan now to reduce the heat losses of her home. The first rule of good planning is that the solution to a problem and the price of that solution are very different matters. “How much will it cost?”, “How much can I afford to spend?” are foolish questions to ask at the start, as Mark should have known. Better to begin with “What will solve my problem?” or “How can I achieve my goal?” Only after we know the solution can we figure out how much it will cost, be it all at once or spread out over several years.

Good news for Deirdre: significant efficiency improvements are possible with relatively easy fixes. The average house loses over 35 percent of its heat through air leaks, and more than 17 percent through an unsealed and uninsulated basement ceiling. That’s a combined 52 percent in savings. Deirdre may not even need to spend as much as $18,000.

What about your house?  The leakiest house we audited lost over two-thirds of its heat through air leaks, the tightest only 2.6 percent. That’s a huge range. An energy audit is the only way to find out how much energy you are losing, where, and what you could do about those losses, without causing new problems.  The audit report should provide you with a detailed analysis and a set of prioritized recommendations for specific improvements to your house, including their estimated break-even cost.

An independent auditor will not give you a cost estimate to do the tasks (if he did, he would not be independent). But he will calculate how much you should be able to spend on each item and break even over a given period of time. A professional audit is not a marketing device. It will not feature self-serving recommendations, or ones that look good on paper but may cause more problems than they solve. Tightening a house, for example, will reduce air leakage, but may also create moisture problems where there were none before – resulting not only in unhealthy mold and mildew but also rot damage to the structure.  The tighter house mentioned above, for instance, had to install heat recovery ventilation before anything else.

Select your energy auditor and weatherization contractor carefully. Easier said than done? Indeed, but the more you know about your house and its workings the better prepared you will be. The basic science involved is not rocket science. You should understand it. Engage people you consider hiring in conversation about this science. True professionals will be happy to discuss questions or issues you may have – and, importantly, will be frank about the limits of their own knowledge and what they can promise to accomplish. For example, it is fairly easy to determine if there is insulation in your walls,  not so easy to tell how much  --  without radical “exploratory surgery” you may not wish to consent to.  The Midcoast Green Collaborative offers regular home energy clinics and adult education classes on what you need to know and how to apply it in your own home. No questions barred. I hope Deirdre can make the next one. In spite of Mark, she is still ahead of the game: she had her audit, all she has to do is act.

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