What is Carbon Matching?

To drive investments to the right places, clean energy buyers need to measure what matters most: emissions. That means we need to modernize the accounting system to focus on the emissions impact of energy procurement.

Today, organizations report greenhouse gas emissions using the Greenhouse Gas Protocol (GHGP). For Scope 2 emissions - those from purchased electricity - the GHGP allows companies to use the market-based method (MBM) to report emissions by matching 1 megawatt-hour (MWh) of electricity load (Load) with 1 MWh of clean energy (RE) purchased within the same market. Any unmatched load is multiplied by the appropriate emission factor.

This approach is based on a fundamental assumption that all electricity in a given market over a given year has a uniform carbon intensity. However, advances in data availability reveal that this approach fails to reflect real-world variations in grid emissions throughout the day and across different regions.

“Carbon matching” (also called “emissions matching”) is an innovative new accounting methodology that measures the heart of what matters — the emissions. By using location-specific emissions factors, location-specific emissions factors, carbon matching more accurately reflects and measures real-world variations in grid emissions.

The proposed carbon matching approach calculates emissions by netting induced emissions from load and avoided emissions from clean energy investments:

Induced Emissions from Load: Multiply corporate load by the relevant Marginal Emission Rate (MER) for the specific time and location of consumption.

Avoided Emissions from Clean Energy Investments: Subtract the generator's emission rate from the relevant MER to the time and location, then multiply by generated energy

By capturing fluctuations in grid emissions based on time and location, carbon matching provides a more accurate measurement and deeper insights into the actual emissions induced by operations and displaced by clean energy purchases.