Case Histories (Real-World Solutions)

Energy Efficiency Made Easy

Energy Efficiency

Miami University maintained the architectural integrity of their historic residence halls and also realized great energy savings, with help from Mitsubishi Electric VRF systems.

In 1825, Miami University (Oxford, OH) built the three-story Elliott Hall men’s residence and its mirror image, Stoddard Hall, nine years later. In 1972, both halls were placed on the National Register of Historic Places. In 2010, Miami University (Miami) tasked its physical facilities department with developing a utility master plan to grow its campus and shrink energy costs. Miami made geothermal cooling and heating a centerpiece of its sustainability strategy and committed to ending on-campus coal burning by 2025.

With Miami’s sustainability goals and the unique cooling and heating requirements of the two older buildings, they immediately thought of Variable Refrigerant Flow (VRF) systems from Mitsubishi Electric Cooling & Heating (Mitsubishi Electric). The team was impressed by the level of engineering design, but was really sold by the simultaneous cooling and heating capability. Energy modeling also showed a total building energy usage of 43 kBTU/h per square foot per year.

Seventeen 600-foot-deep geothermal wells were placed under the surrounding sidewalks. With no modern footings 150 years ago, there was no space for the Mitsubishi Electric water-source heat pumps. Easy-to-access mechanical rooms were built into each hall’s attic for three heat pumps and associated controls hardware.

To maintain the building’s architectural integrity, custom cabinets were designed and built to house the indoor units. These cabinets were only possible because of the two-pipe system design.

Metered as one, the two halls showed 2010-2011 annual energy usage of 740,000 kBTU/h. Following the Mitsubishi Electric installation, this number dropped to 346,000 kBTU/h — a 61 percent decrease in energy consumption compared to 2010. The oldest buildings on campus are now the most energy efficient.

Miami is so impressed with Mitsubishi Electric systems that they are now their system of choice for all new outlying buildings not tied into the central plant.

This article originally appeared in the issue of .