Having a heat pump transfer the energy to heating water that is then circulated in radiators is becoming quite common in the Nordics, and often used as a replac

Having a heat pump transfer the energy to heating water that is then circulated in radiators is becoming quite common in the Nordics, and often used as a replacement for an oil burner. It's more efficient than a regular heat pump that just uses hot air to warm the home. Of course dealing with crappy insulation can often be more bang for buck.