1. Pumping Imbalance
Initially it was established that Purdue had a major pumping imbalance on their campus. WM Group completed a hydraulic analysis of the university campus to determine all losses within the system. With minor control changes, WM Group reduced the electric load by 1 MW as a result of minimizing all losses and shutting down over 100 building pumps.
2. Chilled Water Quality
High short temperatures were identified on every chiller on campus. With further investigation, it was found that the chilled water quality was causing poor heat exchange and tube fouling in the system. Improving the chilled water quality would result in a payback of months.
3. Plant Re-engineering
By identifying more efficient strategies and controls, WM Group could optimize the 40,000 ton chilled water system by reconfiguring and sequencing the current equipment. The proposed recommendations consisted of Condenser Water System Optimization, conversion to Variable Primary Pumping, Near Optimal Chiller Staging, re-piping, and additional valve automation. The recommendations would results in hundreds of thousands in annual savings.
4. Water Side Pre/Free-Cooling
A substantial amount of savings on energy and equipment lifetime was recognized through the proposed addition of water side free cooling. Through the utilization of cooler ambient conditions, the substantial winter time load of 5000 tons would be maintained without running chiller equipment. Not only does this extend the lifetime of chiller assets, but it reduces energy cost by a half of million dollars.
5. Building Controls: Reduction in Simultaneous Heating and Cooling
It was found that major building control imperfections were causing a high simultaneous heating and cooling load in the buildings. Even reducing the concurrent campus load by 25% resulted in millions of dollars. An additional study of a small sample of buildings completed by WM Group resulted in major savings as well as improved comfort for occupants.