Because of advances in technology, efficient small gas turbine generators are becoming available. Simultaneously, electric utilities have become deregulated in some regions of the United States. These two factors combined encourage the decentralization of electric power generation. Decentralized power generation makes possible the recovery of the exhaust thermal energy that is a byproduct of power generation and is rejected at central power plants. Cogeneration technology is economical for facilities that have a high uniform thermal demand, high utility electric costs, and relatively low natural gas costs. Athletic clubs display these characteristics. They have a large and fairly constant hot water demand due to their showers. Field data obtained at a health club facility shows that about 20,000 gallons of water are consumed each day. A cogeneration system was designed for such a facility, using recently introduced and currently available gas turbine equipment. This design included sizing the cogeneration system, which was accomplished by creating a statistical profile of the field data and performing an economic analysis using the cost of the equipment and the current costs of electricity and natural gas.

The study showed that an 84-kW micro-turbine generator system was appropriate for the health club facility studied. The economic and environmental impacts of that same system were then quantified. The simple pay back period in this particular case was found to be 6.8 years. After the pay back period, it was found that the facility would continue to save $20,800 per year throughout the life of the cogenerator. The excess natural gas energy consumed by the turbine generator system over the current gas-fired water heaters results in a slight increase in on-site carbon emissions. However, the reduction in electricity provided by the central power plant results in a decrease in carbon emissions at the power plant, which far exceeds the increase at the club site. Comparing the current system with the cogeneration system, the micro-cogeneration energy system reduces emissions by 46.7 tons of carbon per year. For a system life of 20 years, the net result is a profit of $146.51 per ton of reduced carbon emissions. Notice this is a profit, not a cost. Studies have claimed that reducing carbon emissions costs $100-200 per ton of carbon. Those studies did not consider the new technologies that are now available.