Description: Ball State University in Muncie, Indiana replaced four aging coal-fired boilers with a campus-wide geothermal heat pump heating and cooling system. Built in two phases from 2009 to 2014, Ball State’s district-scale geothermal heat pump system heats and cools 47 buildings, covering 7.5 million square feet of space. The project reduced campus-wide carbon emissions by approximately 50% and continues to save over $2 million annually on operations. Emissions attributed to the campus are expected to be further reduced as Ball State explores opportunities for virtual power purchase agreements with developers of solar or wind projects both nearby and in other parts of the country.

Geothermal heat pumps use the constant temperatures beneath Earth’s surface to heat and cool buildings. Geothermal heat pumps transfer heat from buildings into the ground during the summer, and transfer heat from the ground into the buildings during winter. And the district-scale network enables the ‘trading’ of energy from one building to another, enhancing overall performance. The systems offer the benefits of reducing or eliminating the need for fossil fuel combustion in buildings or on campuses and reducing overall energy requirements for heating and cooling buildings. Additionally, operating and maintenance costs are reduced, less water is consumed, and (when coal-fired boilers are decommissioned) coal and coal ash handling/disposal costs are eliminated.

Many college campuses throughout the U.S. have implemented variations on the Ball State University geothermal heat pump system with sizes ranging from a few buildings to nearly all campus buildings. Geothermal heat pump systems are also being implemented in private sector developments and are being promoted by New York State to grow community heat pump networks.

Smith College in Northampton, Massachusetts will break ground in May, 2022 on a bold geothermal campus energy project that will lower the college’s carbon emissions by 90 percent, allowing Smith to become carbon neutral by 2030. Other universities employing geothermal heat pump systems include Colorado State University, Hamilton College, Harvard, Princeton, University of Illinois, University of Maine, University of Notre Dame, and Yale, to name a few.

In a technologically updated and expanded variation of the Ball State University project, Stanford University used heat pumps (heat recovery chillers) to recover waste heat from over 300 buildings (12 million square feet); the system replaced a gas fired cogeneration plant and a campus-wide steam distribution system. Reduced energy losses (compared to steam) from the new hot water distribution system and heat recovery chillers powered by renewably generated electricity reduced campus energy use by 50% and greenhouse gas (GHG) emissions by 68%. Subsequent to project completion, direct access to additional renewably generated electricity reduced campus emissions by nearly 80% from 2011 peak levels.

In its 2015 report, District Energy in Cities – Unlocking the Potential of Energy Efficiency and Renewable Energy, the United Nations Environment Programme envisions an evolution from 2020 to 2050 to “fourth-generation” district energy systems. Increasing development of district heating and cooling systems that rely on waste heat recovery, heat pumping from ground and water bodies, and integral use of renewable energy were deemed necessary in order to achieve needed global GHG reductions.

Goal: 

• Reduce carbon dioxide (CO₂) emissions.
• Reduce energy consumption.
• Transition away from fossil fuels for heating and cooling buildings.