Case study: Reducing reheat energy use

An energy recovery chiller allowed the Aurora Medical Center in Grafton, Wis. to achieve higher energy efficiency, according to a case study on the Consulting- Specifying Engineer website.

Design engineers for the 526,000-square-foot greenfield facility were challenged to provide a LEED Silver hospital while demonstrating an acceptable payback of the additional first cost, the study said. Reheat energy, the largest energy use in typical health care facilities, was a primary focus of the team’s energy-saving strategies.

The solution was an energy recovery chiller, which delivered the largest savings of any energy reduction item chosen for this project. This offered significant reheat energy savings while maintaining the use of the conventional variable air volume with reheat system that was used throughout Aurora’s network of facilities.

The additional first cost for the energy recovery chiller was $360,000, with an annual savings of $120,000 — demonstrating a first-cost payback of just three years. The three-year payback did not include the incentives provided by the local utility company.

Read the case study.