Mayo Clinic – Wenjie Zhao – 2018

Goals

Mayo Clinic, a nonprofit health care organization, has set a new goal of reducing 30% of its total energy use intensity (EUI) between 2010 and 2025. EDF Climate Corps fellow Wenjie (Linda) Zhao was enlisted to help achieve this goal by analyzing usage and finding conservation opportunities in two of its least energy efficient buildings, the Medical Sciences Building and the Mayo Building.

Solutions

After collecting and analyzing energy use data and working with the Energy Management Team, Zhao helped identify underlying causes for the buildings’ energy inefficiencies. One underlying cause of energy inefficiency in the Medical Sciences Building was due to fume hoods, which draw considerable energy to ventilate the air. To combat this problem, Zhao recommended a sash management and fume hood VAV control program in addition to a VFD upgrade and DDC/ VAV upgrade.

In the Mayo Building, exam rooms and offices are heavily used and have inefficient air exchange and pressure systems. Zhao created a program that includes better scheduling, fine-tuning supply air in rooms, implementing heat-recovery, lighting retrofits, plug-load management, and elevator regenerations. To increase the overall effectiveness of these programs, she also recommended developing an employee engagement plan to educate clinical staff about their importance and what they can do to help increase energy efficiency.

Potential Impact

In fewer than 5 years, Zhao’s energy efficiency projects could reduce Medical Sciences Building’s energy consumption by 23%, translating to $150,000 in net energy costs, which equal more than 1.5 million in KWh. In the Mayo Building, energy consumption could be reduced by 20%, meeting the 120 EUI goal. The project would provide a total annual saving of $700,000 with more than 7 million saved in kWh.