Scope 2 Emissions are indirect greenhouse gas emissions generated by electricity purchased from the grid and used by a building’s equipment and systems. These emissions occur at the power plant and during transmission to the building, representing the environmental impact of grid electricity consumption. Scope 2 typically constitutes 50-70% of total building emissions.
Technical Details
Scope 2 emissions depend on regional grid composition and are calculated by multiplying kilowatt-hour consumption by the grid’s emission factor. Average U.S. grid emission factors are approximately 0.42 kg CO2e/kWh, but vary from 0.2 kg CO2e/kWh in renewable-heavy regions to 0.6+ kg CO2e/kWh in coal-dependent areas. HVAC cooling loads, lighting, and plug loads drive Scope 2 emissions. The Greenhouse Gas Protocol distinguishes between location-based emissions (using regional grid data) and market-based emissions (using renewable energy credits purchased).
Reduction Pathways
Scope 2 emissions decrease through on-site renewable energy generation, energy efficiency improvements, and purchasing renewable energy credits. Converting to electric heat pumps effectively reduces Scope 2 by displacing natural gas use, though the benefit depends on grid decarbonization trends.