Clean Energy Score
The Clean Energy Score recognizes miners with operations primarily powered by non-emitting electricity sources (wind, solar, nuclear, and hydro) by evaluating the proportion of their electricity consumption that is supplied by clean energy via the local grid mix.
The Clean Energy Score is calculated by:
Multiplying the total electricity use at a mining site by the proportion of clean energy in the grid mix supplying that site1;
Aggregating the value of (1) for all mining locations; and,
Dividing (2) by the miner’s total electricity consumption across sites.
The Clean Energy Score may be calculated using either annualized electricity demand and grid mix values or more granular data (e.g. monthly or daily) values.
1 Global resource/fuel mix data is sourced from the Environmental Protection Agency, the Environmental Information Agency, Statistics Canada, and similar sources.
Grid Impact Score
The Grid Impact Score recognizes miners that pursue sustainability strategies driven by market-based clean energy purchases and participation in demand response programs.
The Grid Impact Score is calculated by:
The emissions implications of a miner’s operations and the emissions mitigation potential of its renewable energy purchases, based on marginal emissions data; and,
The miner’s contributions to grid stability via participation in demand flexibility programs.
The net emissions impact of a miner’s operations and renewables purchases (item 1 above) accounts for 70% of the Grid Impact Score; grid stability contributions (item 2 above) account for the remaining 30%.
The Grid Impact Score is calculated as follows:
= Market-based clean energy purchases from a given location2
= Marginal Emissions rate 3,4
= Grid Stability Score, expressed as 0, 50, or 100.
= Miner did not participate in a market-based demand response program during the reporting year
= Miner enrolled in a market-based demand response program but did not participate in any flexibility events
= Miner enrolled in a market-based demand response program and participated in one or more demand response events (i.e. delivered load reduction when dispatched)
2 Clean energy purchases reported within the Grid Impact Score must be documented in alignment with GHG Protocol Scope 2 Guidance (https://ghgprotocol.org/scope_2_guidance).
3 For more on marginal emissions, see https://rmi.org/combating-climate-change-measuring-carbon-emissions-correctly/
4 Marginal emissions data is sourced from the Environmental Protection Agency, the IFI Technical Working Group on GHG Accounting, and similar sources.