williamwright wrote in news:hu14m7Fpf26U3
@mid.individual.net:

On 05/10/2020 12:28, JohnP wrote:
A black radiator gives off more heat.

Why should the efficiency of a surface in absorbing light affect its
efficiency in radiating heat?

Bill


See the specifications for radiators of the same sizes in different
finishes. It is significant. Reflection must go inwards as it were!