A major hospital that treats critically ill patients cannot afford power failures. Facing intermittent power problems — and needing to replace old boilers — the 536-bed University of Illinois Hospital installed a 24 MWe cogeneration system for its campus in Chicago. Powered by three Taurus 70 natural gas turbine generator sets, the system fulfills 100 percent of campus power needs in winter and 72 percent in summer. The system provides low- cost steam for space heating and domestic water heating for 32 campus buildings. It also supplies heat for medical equipment sterilization and food preparation and delivers summer cooling through several absorption chillers. If utility power fails, the Solar turbine generators can operate in island mode, disconnected from the grid.
The turbine generators are housed in a 6,000-square-foot building next to the hospital’s boiler plant. Turbine exhaust passes through two heat- recovery boilers with fresh-air ring capability. To optimize energy costs, operators use real-time energy monitoring. Besides saving on energy, the cogeneration system produces lower NOx emissions than the old boilers.
“Rather than just replace the boilers, it made sense for the medical center to go to cogeneration,” says Ron Demski, PE, project manager with the engineering firm EME of Chicago. “By making just an incrementally greater investment, they were able to make electricity and steam from the turbine exhaust heat.”
- Owner: University of Illinois Hospital
- Project engineering: EME, LLC
- Engineering, procurement and construction: Solar Turbines, Inc.
- Product: three 8 Mwe Taurus 70 natural gas turbine generator sets with heat recovery boilers
- Customer value: power reliability, energy savings, reduced emissions and island mode operation
- Three 8 Mwe Taurus 70 natural gas turbine generator sets
- Three heat recovery boilers (steam up to 180,000 pounds/hour)
- Single-screw gas compressors
- Absorption chillers (total 4,600 tons)
- Real-time energy monitoring system