ENERGY STAR Score for Parking

The ENERGY STAR score provides a fair assessment of the energy performance of a property relative to its peers, taking into account the climate, weather, and business activities at the property. Parking areas are not eligible to earn the ENERGY STAR score. However, because parking is a common amenity at other commercial building types (i.e., office and hotels), the ENERGY STAR score does make adjustments to accommodate for the presence of parking. The goal of the ENERGY STAR score is to rate the energy performance of the primary use of the building, not the parking.

• Technical Approach. An engineered model is developed to estimate the energy use for parking. This estimated energy use is subtracted from the building’s actual energy use, yielding an estimate of energy use of the building without parking. This allows the building to be evaluated as though it does not have parking.
• Property Types. Parking areas can be entered for all property types and will be incorporated into the ENERGY STAR score for eligible property types. This includes open parking lots, completely enclosed parking garages (walls on all sides), and partially enclosed parking garages. If parking space is separately metered from the main facility with which it is associated, it does not need to be entered into Portfolio Manager.
• Adjustments. The parking model is based on engineered assumptions regarding basic energy requirements for parking that includes:
  • Lighting Energy. Lighting is required for all parking areas, with power density and hours of operation that vary by the type of parking.
  • Ventilation Energy. Ventilation is required for fully enclosed parking structures that have no access to natural ventilation.
  • Heating Energy. Heating may be provided in enclosed parking garages in very cold climates.
• Release Date. The model is updated periodically as industry standards for design and operation are updated and as better engineering data becomes available:
  • Most Recent Update: July 2013
  • Previous Update: October 2007
  • Original Release: June 2001

This document presents details on how the ENERGY STAR score accounts for parking. More information on the overall approach to develop ENERGY STAR scores is covered in our Technical Reference for the ENERGY STAR Score, available at www.energystar.gov/ENERGYSTARscore.  The subsequent sections of this document offer specific details on the development of the parking model.