Global warming, rising fuel prices, and renewed interest in energy efficiency have led to reanalysis of the significant heat loss that occurs in boiler exhaust stacks, typically found in conventional central steam heating plants. Thermoelectric energy converters can turn large waste heat flows into usable electricity, all without moving parts. Although the efficiency of this conversion is often quite low, usually 5-10%, new materials and designs promise improved performance. Since the devices recover useful energy from something that is completely wasted, and directly reduce global warming in the process, even a low efficiency conversion makes environmental sense, and might even have an economic payback over time. The project involves design and testing of devices intended for installation on boiler stacks at the central steam plant of Kalamazoo College.