A study by British Gas Corp. shows that available devices can reduce the enrgy consumption of swimming-pool buildings by recovering heat from the exhaust air for use in satisfying some of the air and/or water heating requirements of the building. The efficiency and capital cost of installations will vary with the type of device used: Run-around coils and plate heat exchangers are low-cost devices, while heat pumps, which may offer greater savings in operating costs, are more expensive to buy. British Gas Corp.'s THERM computer program (available for use by designers and consultants) is capable of calculating the energy consumptions of various heating and ventilation systems for the indoor swimming-pool building. Because THERM calculates the fuel consumption for a conventional gas-fired heating and ventilation system and also for those incorporating various heat-recovery devices, it permits an assessment of the comparative benefits of the various schemes. For a typical building containing an 80-ft (25-m) main pool and a 40-ft (12-m) beginners pool, the results show that if conventional ventilation air rates are employed, adding a direct-fired air heater and exhaust-air heat recovery to the conventional gas-fired boiler installation can save up to 40% in operating costs without modifying conventional ventilation rates.more » If recirculation is allowed, however, for reducing the fresh-air flow rates and a heat pump added to the system to dehumidify the swimming-pool hall air, fuel savings over a conventinal gas-boiler system can reach as much as 60%.« less