Subsidies for modernizing homes exist for a long time in Germany: Tax credits, super cheap loans (0.75% p.a.), financial aid (not having to pay back up to 30kEU

Subsidies for modernizing homes exist for a long time in Germany: Tax credits, super cheap loans (0.75% p.a.), financial aid (not having to pay back up to 30kEUR)... Among the supported measures is: modernizing heating systems.