How Cogen Works
- Two natural gas-fired combustion turbines drive generators to produce electricity.
- The hot combustion gases from each turbine pass through a corresponding heat-recovery steam generator (HRSG) to produce steam. The HRSGs contain duct burners to produce additional steam as needed.
- The high- and low-pressure steam from the HRSGs passes through a single extracting/condensing steam turbine that sends heating steam to the UW and produces electricity for the Madison area.
- The exhaust steam is sent to a condenser and then cooled by cooling towers. This process forms water that is reused.
- Centrifugal chillers provide 20,000 tons of chilled-water capacity. Electric-driven chillers use roof-mounted cooling towers for heat rejection.
- The steam heat and chilled water is used on the UW-Madison campus.
- The electricity is sent to an adjacent substation and then to the Madison area.
For more information
- Technical Fact Sheet [251 kB PDF]