Aha aha aha ahaaaaaaaaaaaaaa but why is it waste heat ? Our lamp is part of the energy make up of our home most of the time.Only a daft haporth like elmagico would go chasing after a car to capture the heat loss from its engine but think of where we would find heat loss that we can prevent become waste heat.Interesting that in past times cattle were housed under the domestic part of farm buildings thus turning the respiratory heat loss from the moos into useful heat.No "waste heat " in yer House of Denmark young Yorick