The Energy Efficiency Personal Credit Is a Yearly Credit, Not a Lifetime Limit.

The energy efficiency personal credit is capped at either 18 hundred dollars if you don't buy a heat pump or a biomass stove or boiler. You can get up to 600 dollars per item, and no more than 18 hundred dollars per year. There is a separate credit for home solar systemsthat solar electric, solar hot water. Small wind systems and geothermal heat pumps that's 30 % with no cap.