ID#5340 made on
EAp2 - Minimum energy efficiency performance
LEED O+M: Existing Buildings
The Fillmore Center is a multi family housing development comprised of 1114 apartment units spread across 10 buildings totaling 1,640,000 sq. ft. There are 5 types of units (studio, one bedroom, etc.)...
The Fillmore Center is a multi family housing development comprised of 1114 apartment units spread across 10 buildings totaling 1,640,000 sq. ft. There are 5 types of units (studio, one bedroom, etc.) Residential buildings of this type are not eligible for Energy Star and therefore require compliance with EA Prerequisite 2 via Options B or C, as appropriate. The LEED-EB:O&M Reference Guide, on page 195, notes that "buildings must have energy meters that measure all energy use throughout the performance period." We are seeking an exception to that requirement due to the owner's inability to achieve whole-building metering, and propose an alternative means for reliably estimating building energy consumption. Fillmore Center management currently collects two forms of energy consumption data directly - whole-building gas consumption and common area electricity consumption. Management does not receive electrical usage information for the tenant spaces because they are all separately metered. Although Fillmore Center management would prefer to install whole-building electric meters to track electricity consumption, the utility provider (PG&E) has repeatedly denied requests to do so or to allow such metering. Consideration was given to collection of historical energy use data from all tenants. Unfortunately, the number of tenants (over 1000) makes this approach cost prohibitive. In the absence of reliable, financially feasible data sources for the entire building(s), we propose to employ a sampling approach to estimate annual energy consumption for the facility. Please note, the sampling approach will inform only the fraction of total building energy use which is currently unknown - all gas consumption and electricity consumption for common areas is known and documented with metered data. We propose the following to achieve EA Prerequisite 2: To develop an estimate of the tenant area electricity consumption portion of total energy consumption for the complex, we will collect a statistical random sampling of energy usage data from the tenants and use this information to extrapolate total tenant area electrical usage for the property. Because a random sample is essential to this process, we will leverage an existing random process - tenant lease renewal - to obtain the appropriate sample. As tenant leases come up for renewal (determined purely by lease durations and timing), tenants seeking to renew will be asked to provide permission/access to utility data for their spaces for the past year, and going forward on a continuing basis. This will ensure that all spaces provide a total of one year or more of overlapping data. All resulting data will be actual metered electricity consumption data, rather than modeled data - it will simply be for a representative fraction of the floor space, rather than the entire tenant-occupied floor area. At a minimum, the sample will represent 10% of total building tenant occupied floor space, and will be balanced by domicile type (studio, 1 BR, etc.) in a manner that correlates with actual distribution of these domicile types. As we collect data, we will continuously update the average energy usage, along with standard deviation. In order to ensure that our sample accurately represents the population, we will continue to collect sample data until the subsequent data consistently falls within two standard deviations of the average. By tracking the data in this manner we can ensure with a 95% confidence interval that our data accurately represents total electrical usage within tenant spaces. The estimated tenant-area electrical consumption data will be integrated with the metered whole-building gas consumption and metered common-area electricity consumption data to produce a highly-informed estimate of total building energy consumption, we will compare this figure against national median energy data as per the requirements of EA Prerequisite 2 / Credit 1 Option B/C. Our questions for the USGBC are: Is this an acceptable method to achieve EA Minimum Energy Performance Pre-requisite and Credits? Are there any actions that the USGBC would like to see us take to ensure accurate data collection and benchmarking?
Though the USGBC understands the complexity and challenges associated with collecting and benchmarking whole-building energy consumption, current requirements for basing benchmarking on whole-building actual consumption cannot be relaxed. Energy in tenant spaces must be accounted for through the installation of meters/sub-meters.
Related Addenda (Corrections & Interpretations)