In a first aspect, a system for heating, cooling, or both heating and cooling a room is disclosed. The system includes a panel with a first, second, and third wall. The second wall is disposed between the first and third walls and separated by a plurality of partitions. The partitions create a first and second row of elongated channels. Each channel in the first row is bounded on two sides by two partitions and on two other sides by the first and second walls. Each channel in the second row is bounded on two sides by two partitions and on two other sides by the second and third walls. The first row of channels is a fluid layer configured to allow heated or cooled fluid to pass through. The fluid layer is in thermal communication with the room. The second row of channels is an insulating vacuum layer, with a reduced pressure that is at least 20% less than atmospheric pressure.