Portfolio Manager tracks several metrics related to your building's greenhouse gas (GHG) emissions:
- Total Emissions is the sum of your Direct + Indirect emissions (note - your Avoided Emissions are not subtracted here, but can be tracked separately):
- Direct Emissions are associated with onsite fuel combustion (e.g. combustion of natural gas or fuel oil).
- Indirect Emissions are associated with purchases of electricity, district steam, district hot water, or district chilled water. These emissions occur at your utility’s plant not at your property, but they are a result of your property’s energy consumption and therefore contribute to your overall GHG footprint.
- Avoided Emissions - Avoided emissions are the emissions benefits associated with green power use. Avoided emissions may be either onsite or offsite.
- Onsite Avoided Emissions occur when you have an onsite renewable electric system (onsite solar panels or onsite wind turbine) and you retain the rights to the Renewable Energy Certificates (RECs).
- Offsite Avoided Emissions occur when you purchase green power from your utility or an independent supplier and you own the claims to the RECs. They can also occur in the case of REC arbitrage, a transaction where you sell the RECs associated with your own onsite system and purchase other substitute RECs. In this case, the avoided emissions associated with your green power originate from offsite sources, not your onsite system.
- Net Emissions - Net emissions are your property's Total Emissions minus the Offsite Avoided Emissions. You do not subtract the Onsite Avoided Emissions to get this net value, because they have already been counted as zero emissions in your Total Emissions (inventory).
In the weeds: The methodology for calculating GHG emissions was designed to be consistent with the Greenhouse Gas Protocol developed by the World Resources Institute and World Business Council for Sustainable Development, and is compatible with the accounting, inventory and reporting requirements of the Center for Corporate Climate Leadership as well as other state and NGO registry and reporting programs.