I heard a paper by Fowlie, Greenston and Wolfram presented at the AEA meetings in Boston in January 2015 on winterizing homes. Three questions addressed were:
1. Why don't poor people apply for free winterizing?
2. How much energy does winterizing save, and is it worth the cost?
3. Do people use more energy after winterization, given that less is wasted?
They spent $50 per household on encouragement of people to apply for the program— 7,000 initial in-person house visits and 2,700 follow-up visits to help with enrollment, 23,500 robo-calls and 9,000 personal phone calls, for a cost of $445,000 for 8,648 households. This resulted in a 5% increase in the number of households participating in the program. That's 432 households. So the cost per household signed up wasn't $50— it was about $1,000. It was hard to get people to sign up even though the average expenditure on fixing up houses for those who did sign up was about $5,000.
The energy auditors estimated an average of 46% reduction in people's gas bills. The actual reductions were about 12%. This meant the winterization flunks cost-benefit analysis, even putting in some extra nudges for global warming.