Power Generation

Electricity generation at Massachusetts Institute of Technology’s (MIT) co-generation plant could soon get even more efficient if a project to harness excess heat works as planned.

Graduate students, Andy Muto, Daniel Kraemer and Bryan Ho, have been working on a thermoelectric system to extract extra electric power from heat currently going to waste from hot-water pipes or exhaust flues at the Institutes’ co-generation plant.

Currently, the plant uses high temperature steam generated by a gas-fired boiler to drive a steam turbine to generate electricity, which is then used directly for heating and cooling. However, although the steam returning to the plant after being piped around the system is not hot enough to drive the turbines, the residual heat can still be used to provide some additional power if passed through a thermoelectric device. An added bonus is that the amount of heat vented to the outside is reduced.

The students have designed a heat-exchange system resembling a car radiator that can be placed in the hot-air or hot-water systems to capture the waste heat. The concept is already being tested on one of the plant’s roof-top flues and the students hope to install a prototype system in the plant by the end of the summer.

MIT’s co-generation plant was installed ain 1995 and generates 22 MW of electricity, meeting the electricity, heat and air conditioning demands for 80% of the campus’ buildings.

For further information: http://web.mit.edu/newsoffice/2008/thermo-0724.html