The Non-Business Energy Property Credit has a lifetime credit limit (per taxpayer, or couple if living & filing jointly, not per house) of $500. This is the more common credit, for electric heat pumps, furnaces, fans, biomass stoves, water heaters, skylights, doors, etc (rather than the big ticket solar/geothermal/wind/fuel cell items).
So even though you've made upgrades to a different house, the limit for this credit is placed on the taxpayer(s).
