Stakeholder Collaboration Results in Successful Rooftop Unit Retrofit

By Michael Deru, NREL on Mar 14, 2016

Commercial office buildings are a great target for efficiency projects due to their structured occupancy schedules and high energy intensity.  Proposals that make a strong fiscal case on paper, however, oftentimes fail to reach execution due to the ‘split incentive’ that exists among the different stakeholders in a leased space.  Building owners, property managers, and tenants must all decide who will pay for a project, and who will see the benefits before offering up funding.  This process requires a high level of cooperation and communication that is vital to a project’s success.

The Better Building Alliance’s Space Conditioning Technology Solutions team recently released a case study highlighting a capital-intensive 66 rooftop unit (RTU) retrofit that featured successful collaboration between five different stakeholders.  The 140,000 square foot office building located in St. Albans, Vermont is owned by Elman Investors, managed by Pizzagalli Properties, leased by the U.S. General Services Administration, and occupied by the U.S. Citizenship and Immigration Services.  Efficiency Vermont, a nonprofit statewide energy efficiency utility, proactively approached the property and became involved due to the need for the state to reduce the electrical load on the grid in this region.

An investigation by Efficiency Vermont revealed several potential benefits beyond the energy and demand reductions which helped make the project more attractive for all the parties involved.  The 66 aging RTUs, in sizes ranging from 1.5-12.5 tons, were in constant need of repair and maintaining them was getting to be expensive.  The outdated manual controls made it difficult to sustain consistent temperatures, and the units struggled to provide comfortable conditions during the summer months.  With the wide variety of high efficiency RTUs available on the market, Efficiency Vermont encouraged replacements with exceptionally high-efficiency units meeting the RTU Challenge specification, and the decision was made by all the stakeholders to replace the old units.

The Efficiency Vermont team initially predicted that the retrofit would save 289,000kWh per year, reduce peak demand by 118 kW, and lead to $41,200 in avoided utility costs.  However the first ten months of data shows that the facility is on track to double those saving estimations.  Incentives provided by Efficiency Vermont reduced the simple payback to 3.8 years.

The project was recognized with an award from the Advanced RTU Campaign for the highest number of high-efficiency RTU installations by a government organization in 2015.  The Advanced RTU campaign is a national initiative designed to encourage building owners and operators to take advantage of savings opportunities from high efficiency RTUs via technical assistance and resource publications.