The Importance of Integrated Design, Commissioning, and Building Tuning: A Grocery Store Case Study

Jonathan Heller, Ecotope, Inc.
David Baylon

Keywords

Abstract

Significant savings in heating energy can be achieved through proper application of refrigeration heat recovery techniques with minimal increases in refrigeration energy. However, barriers exist to widespread adoption due to the current specialization in the construction industry. We will detail the process needed to achieve modeled natural gas savings through direct condensation of refrigerant in the main air handler, and the resulting energy impacts on refrigeration energy and heating energy.

The grocery store construction industry for regional chains and independents in the Pacific Northwest region is compartmentalized into refrigeration, electrical, and HVAC specialties. The most effective refrigeration heat recovery involves integrated knowledge and work that affects the scope of each of those trades, and is difficult to achieve without integrated design support, careful commissioning, and tuning of the building during actual operations.

Primary barriers faced by the project described in this paper included the limited understanding of refrigeration by the design build HVAC team and the narrow focus of refrigeration contractors for optimizing the operation of only the refrigeration equipment. The inexperience of the HVAC team led to improperly sized heat recovery coils and serious problems integrating control of the heat recovery and gas heating. Early modeling indicated that the vast majority of heating energy could be offset through use of heat recovery. However, it took more than a year of on-site commissioning, billing analysis, and building tuning to get all systems setup as originally intended to achieve modeled savings.