Scope 5’s CBECS Benchmarking library combines annual energy use intensity (EUI) figures for office buildings with greenhouse gas (GHG) emissions factors for electricity and natural gas. This library makes it easy for Scope 5 users to estimate GHG emissions for offices for which they do not have access to electricity or natural gas consumption data.
The EUI figures in this library come from the Commercial Buildings Energy Consumption Survey (CBECS), a review conducted by the U.S. Energy Information Administration (EIA) to understand building characteristics and define figures for average EUI for different ‘Principal Building Activities’. In the words of the EIA, CBECS is the “only nationally representative source of statistical information on energy-related characteristics, consumption, and expenditures for the nation's 5.6 million commercial buildings totaling 87 billion square feet of floor space.” Two results of CBECS are of special interest to the Scope 5 community: the national map of climate regions and the detailed tables delineating annual energy use intensity by climate region.
Each of the factors in this library applies to one CBECS climate region, and can be used when the ‘Principal Building Activity’ is Office. Two activities are included in this library:
- Natural Gas
If you have a compelling interest in seeing other ‘Principal Building Activities’ or reporting activities supported in the Scope 5 CBECS Benchmarking library, please contact us to discuss your needs.
Disclaimer: The CBECS-eGRID region combinations were created by Scope 5 using the above maps, the eGrid Power Profiler Emissions Tool which offers a lookup by zip code, and the CBECS tables of regions by state and county. Since no official published overlap of the CBECS and eGRID regions exists, we recommend consulting the above maps and tools to confirm each facility’s location and designation.
For each combination, the CBECS region factor for annual electricity EUI (in units of energy/area) is multiplied by the eGRID emissions factor (in units of emissions/energy) to produce conversion factors in emissions per unit area. Note that these emissions factors are expressed as weight per thousands or millions of square feet. The energy conversion factor (energy/area) comes directly from CBECS Table C20.
Natural Gas Resources
The natural gas resources combine the TCR emissions factor for US weighted average (commercial, by volume) in units of emissions and energy/volume with the annual natural gas EUI for each CBECS region in units of volume/area to produce emissions and energy per unit area.
A Note on Heating Values
For all values by energy - for which the denominator is in mmBtu (or any energy unit) - Scope 5 has chosen to use the Higher Heat Value (HHV), as opposed to the Low Heating Value (LHV), to calculate the emissions factor. In GHG reporting the HHV is the more conservative value as it is always slightly higher or equivalent to the LHV, resulting is a slightly higher (or equivalent) emissions factor than would be calculated by using the LHV.
Global Warming Potentials (GWPs)
Following the Greenhouse Gas Protocol recommendation, all Scope 5 standard resource libraries use global warming potentials from the IPCC's Fifth Assessment Report (AR5) as of February 13, 2017.
The Scope 5 CBECS library is updated when any of the source authorities publish updates. The most recent set of emission factors combine CBECS data published in 2016, electricity factors from the EPA’s January 2020 update and natural gas emissions factors from TCR’s April 2020 update. It is updated when any of the authorities publish changes.
The emission factors released by TCR vary from time to time due to rounding. As such, users may find relatively small variations that are not attributable to actual changes in activity so much as to changes in the rounding of TCR's emission factors on certain years.
Scope 5 cannot guarantee that use of the Scope 5 CBECS Benchmarking Resource Library will produce a report that is compliant with any particular protocol. We recommend working with a sustainability specialist versed in GHG emissions reporting to ensure the report is fully compliant with the intended use.