Whilst activity data is the most accurate method for calculating your emissions, sometimes it is not possible to obtain this data. As an alternative, you can use the below method as an approximation to calculation your carbon emissions.
European offices
1. PCAF
Create an account. This is free of charge and the user can create their own account.
Download the dataset in Excel spreadsheet format.
Select your country where your office is located in Europe.
Select how you would like to calculate your emissions: using floor space, energy consumption or energy efficiency rating.
Calculate your carbon emissions (in t CO2eq) (Here is an illustrative example for calculating annual emissions for office spaces in Belgium):
Energy consumption (MWh) method
Carbon emissions = MWh energy consumed * emission factor (0.2403 for Belgium)
Floor space (square meterage) method
Carbon emissions = square meters of office space * emission factor (0.0483 for Belgium)
Energy (EPC) rating method
Select your energy rating
Select your country
The resulting emission factor equates to total emissions
USA offices
1. CBECS
Data tables for commercial buildings using only electricity for certain end uses. These estimates may serve as a baseline for electrification policies and to understand the market for all-electric building technologies and equipment.
CBECS data tables are derived for USA, however they can be used for approximations.
Please note that emission factors are not provided by CBECS; they provide conversion tables to calculate your energy consumption e.g. kWh for typical office space.
You will need to source emission factors for electricity usage in your country where your office operates to calculate your total carbon emissions.
You can calculate important energy consumption metrics, and other building characteristics like floor space and energy consumption end-use.
An example workflow for calculating your electricity consumption in kWh for your office if you know the geographic location / climate zone it is located in:
Select Select 'Consumption and Expenditures' tab
Consult the map provided by CBECS to determine which climate zone your office is located in
Navigate to Table C20: 'Table C20. Electricity consumption and conditional energy intensity by climate zone'
Select the row 'All buildings' under building type
Navigate to the correct climate zone and select the correct Electricity energy intensity (kWh / square foot)
Multiply the electricity energy intensity (kWh / square foot) * square footage of office space
KWh consumed = square footage of your office * climate zone energy intensity (kWh / square foot)
An example workflow to calculate your electricity consumption in kWh for your office if you do not know the office location / climate zone it is located in:
Select 'Consumption and Expenditures' tab
Navigate to table C22: Electricity consumption and conditional energy intensities by building activity subcategories
Select ‘Office’ under building type
Select ‘Administrative or professional’ subcategory
Select emission factor 13.6 kWh per square foot
Calculate the kWh of energy consumed in your office using this equation:
KWh consumed = square footage of your office * 13.6
Entering your emissions in the KEY ESG portal
Within the KEY ESG app, you should categorise your leased office emissions in Category 3.8 Upstream leased assets, and enter the final kgCO2e value under the "Direct Entry" method.
Support
If you have any questions, do not hesitate to reach out to the KEY ESG team at supporty@keyesg.com. We will be happy to help.