The federal Weatherization Assistance Program allows crews to spend as much as $6,500 to make low-income homes more energy-efficient.

The Department of Energy gave Texas $327 million to do this work, a sum with which the state Department of Housing and Community Affairs has estimated it will be able to weatherize between 38,000 and 56,000 homes. Through December, Texas had improved just 47 homes, though officials say hundreds more were fixed up in January.

Much of this work is administered through county and local agencies and nonprofits that are being asked to run much more ambitious weatherizing programs.

In Austin, Austin Energy has run a low-income weatherization program since the early 1980s that has spent up to $1,500 weatherizing each of about 500 homes a year. Travis County Health and Human Services spends about the same amount on each unit and has done about 125 homes a year.

Over the next two years, Austin Energy will spend $5.8 million on contractors who will do slightly less than the same number of  homes a year - about 450  - but will be able to spend as much as $5,000 more on each unit. Travis County now has $4.5 million, $2.25 million to do about 400 homes in each of the next two years with the same spending cap.

This cap allows weatherizing crews not only to insulate, caulk and weather strip homes, but to replace old appliances like refrigerators and even air conditioning and heating systems with energy-efficient models. According to the federal rules, crews must be able to prove that for every dollar spent, a dollar of energy savings can be realized over the life of the improvement.

Who is eligible for the program? Families at or below 200% of the federal guideline for poverty. The families must have power bills of $1,000 a year or more. They must be spending at least 11 percent of their income on energy. The households must have small children, elderly or disabled occupants.