In particular, if k L ≫ ≫ k H , then we have T H ′ = T H T L ; T L ′ = T L This is often the case with practical heat engines in power generation plants, where the work fluid can only spend a small amount of time with the hot bath (nuclear reactor core, coal furnance, etc), but a much larger amount of time with the cold bath (open atmosphere, a large body of water, etc).