Implementing a Resilient, Efficient, and Cost-Effective System Using Thermal Energy Storage
In 2024, St. Olaf College partnered with Ever-Green Energy for an energy study to identify and develop opportunities to increase energy efficiency, reduce energy use, and provide a plan to increase cooling redundancy. The campus has three aging chillers unable to meet historic peaks, requiring an increased cooling capacity.
Ever-Green’s study determined a thermal storage tank with 800-ton chiller to be an optimal alternative, increasing both redundancy and resiliency. By implementing Federal IRA tax credits and Xcel Energy rebates, it is also a more cost-effective solution. Through annual rebates alone, the College is expected to reap significant savings over the next two decades with a system that reduces peak load, meets financial goals, and reduces annual operations costs.
Ever-Green identified additional recommendations to St. Olaf’s steam district heating system, district cooling system, and electrical systems, including:
- Planning for cooling refrigerant and equipment end-of-life
- Additional equipment to match current and future energy demands
- Implementation of energy conservation measures within campus buildings
- Renovation of existing buildings and design new buildings to be compatible with future energy sources, including renewables
- Additional safety measures for staff and contractors
Ever-Green’s Role
Ever-Green conducted an energy study analyzing St. Olaf’s existing energy operations, energy efficiency and performance, and reliability of the heating, cooling, and electrical systems. Ever-Green also assessed value and risk operation protocols and provided the College with recommendations for continued success of existing and new equipment.
Once the thermal energy storage tank and chiller were identified as the ideal solution, Ever-Green served as the design engineer for plant modifications needed to integrate the tank and chiller into the central utility plant.
Ever-Green functions as the owner’s representative for the design-build construction of the 2M gallon thermal energy storage tank. Ever-Green is monitoring project work and structure meet the requirements to utilize the Federal Inflation Reduction Act of 2022 tax credits.
About St. Olaf College
Located on 300 acres in Northfield, Minn., St. Olaf College is a residential liberal arts institution with an enrollment of more than 3,000 students offering over 85 undergraduate majors, concentrations, and pre-professional tracks. 95 percent of recent graduates are employed, in graduate school, or engaged in full-time service work. St. Olaf is committed to meeting the demonstrated financial needs of every student with 99 percent of students receiving scholarships or grants.
Grounded in a Lutheran tradition, St. Olaf students and faculty come from a wide range of religious traditions, including those who do not claim any faith tradition. Visit stolaf.edu.
