Teschler on Topic
On Twitter @DW_LeeTeschler
Leland Teschler – Executive Editor
There’s been a lot of bile spilled in the blogosphere recently about a group of economists at the University of California Berkeley and the University of Chicago. The researchers studied Michigan households participating in a Dept. of Energy effort called WAP (Federal Weatherization Assistance Program). WAP gives out grants that let low-income families install energy efficient furnaces, windows, insulation and other measures aimed at cutting expenses for heating, cooling and electricity.
The economists found that money spent on these measures did, indeed, reduce energy consumption. Problem was, investments in energy efficient technologies didn’t pay for themselves. In economic terms, the investments “have negative annual returns both privately and socially (meaning, when the monetized value of the green house gas savings are included),” wrote the economists. Perhaps even more disappointing, the recipients of WAP money didn’t seem to live more comfortably. The households increased their indoor temperatures by less than a single degree on average during the winter months.
These revelations are not good news for those who sell pricey windows and weatherization measures. Predictably, they haven’t taken this news well. Some of the comments online come across as though the economists had claimed Santa Claus was really a vampire.
Not surprisingly, internet kibitzers have suggested the study authors had a conservative political agenda. That’s an interesting claim; one of the authors is a senior fellow at the Brookings Institution, sometimes described in the media as a liberal-centrist think tank. And UC Berkeley, from which two of the authors hail, is not exactly a bastion of conservative thinking.
Other pundants in the green building space claim the study was too small. One I read was indignant that the researchers studied “only” a little over 600 households. In the spirit of generating more heat than light, it never seemed to have occurred to the writer that 600 might be a statistically significant number, given what the economists were trying to discern.
But once you get past the invective and name calling, there are interesting truths illuminated by all the back-and-forth that’s spilling out online. One is that the engineering models contractors use to predict the pay-back of their energy efficiency solutions aren’t particularly accurate. On this score, here is a typical comment: “The NEAT (National Energy Audit Tool) used by the programs they (the researchers) studied regularly under-estimates the efficiency of existing heating equipment. … In the original paper, they estimate that the error in the NEAT tool to be about 25% (sic), since it was predicting heating energy use that was 25% higher than actually measured in those homes.”
Consumers should be troubled that NEAT and similar programs are spewing overly rosy predictions; their models are key selling tools of contractors who peddle weatherization services. Worse, contractors have an incentive to shade the results of these energy audits toward fixes that entail spending significant sums of money.
In contrast, the lesson from the economists is to stick with improvements that don’t cost much. One commentor may have summed it up best: “The study mirrors my personal experience. … Two years ago, I hired a contractor to nail down every board, caulk every gap, apply three coats of paint and blow insulation in the attic. … This improvement reduced my electricity usage by a third … a third! … Overall, … the biggest savings and the most cost-effective savings have come from paint, caulk, insulation and LED lightbulbs.”