Keith Welks, 62
On a crusade since: 1976
Day job: Deputy treasurer, Pennsylvania
Achievement: Made energy-efficient upgrades more affordable
Why he's a hero: A onetime Pennsylvania prosecutor of environmental crimes, Welks in 2005 launched Keystone HELP, a state program that issues low-interest loans to homeowners so they can install energy-saving windows, furnaces, and other upgrades. More than 10,000 loans later -- totaling almost $70 million -- Welks hopes this year to roll out similar programs in other states.
Quote: "Homeowners save money, workers make money, the commonwealth earns money."
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