Case studies have been done where three types of heating systems were compared: convential gas-fired forced air, an infrared, and hydronic radiant heat. The projected energy usage to heat the space was 99,000 BTUH (29 kW) for the forced-air system, 66,000 BTUH (19 kW) for the infrared system, and 33,000 BTUH (10 kW) for the hydronic radiant system.