As clean energy and emissions policies expand beyond traditional renewable portfolio standards in the Western US, and the region looks to regional market coordination to meet clean energy goals, differences in these policies present challenges with consistency, accuracy, assignment of responsibility, and costs.

The contributors to a new whitepaper, Greenhouse Gas and Clean Energy Accounting Methodology Catalog, seek to collate a catalog of greenhouse gas (GHG) and clean energy accounting methodologies in use across the Western US and identify differences in between programs that may impact a state or utility’s ability to meet its objectives. This paper is intended to be a centralized resource and educational tool for regulators, policymakers, and other parties shaping the clean energy landscape.

This catalog was developed through interviews with participating utilities, as well as other research on existing policies. Across the 15 utilities surveyed in this study, Brattle documented at least 56 distinct GHG and clean energy reporting or compliance regimes, categorized as follows:

  • 13 renewable portfolio standards and 9 clean energy supply targets
  • 10 mandatory GHG emissions reporting and reduction programs
  • 9 customer energy mix and GHG intensity disclosure programs
  • 18 voluntary utility and end-use consumer GHG reporting and commitments

The study identified 8 common themes across its utility interviews while developing this catalog:

  • Theme 1: Due to the variety of state policies and voluntary protocols, there is no common, fit-for-purpose GHG emissions accounting methodology and data tracking system for the West
  • Theme 2: When accurate GHG emissions data are not available, a variety of accounting practices are used to approximate Scope 2 and Scope 3 emissions
  • Theme 3: The variety of accounting practices and data sources in use across the West can lead to inconsistencies or differences in estimated GHG emissions
  • Theme 4: Jurisdictional policy frameworks for GHG accounting are not consistent with the physical flow of electricity across broad geographies, electric system operational constraints, and current market structures
  • Theme 5: More accurate emissions rates associated with “unspecified” and wholesale market purchases can enhance trade and full participation in regional markets
  • Theme 6: With the increase in financially enforceable mandates, GHG accounting practices have the potential to introduce risks and costs to utilities and consumers
  • Theme 7: A utility’s position in the value chain can substantially impact the nature of available data and data-sharing needs with contractual counterparties
  • Theme 8: Utilities report increasing demand for transparency and granularity in GHG and clean energy accounting from company boards, end-use consumers, industry advocacy organizations, and lenders

The full report, Greenhouse Gas and Clean Energy Accounting Methodology Catalog, is authored by Brattle Principals Dr. Kathleen Spees and John Tsoukalis, Senior Associate Dr. Long Lam, and Research Analyst Jadon Grove.

This report is developed on behalf of WEST Associates, and in partnership with the Public Generating Pool (PGP) and other participating utilities. WEST Associates is comprised of a group of utilities operating in the Western US with the mission of supporting sound energy, economic, and environmental policies based on excellence in science. The PGP is a collective of generator-owners in the Pacific Northwest with the mission to educate, advocate, and collaborate in support of a reliable, affordable, and sustainable Western power system. This paper is informed by interviews with 15 utilities across the West, many of whom are members of the WEST Associates. WEST Associate utility interviewees include Arizona Electric Power Cooperative, Basin Electric Power Cooperative, Montana-Dakota Utilities, NV Energy, PacifiCorp, Platte River Power Authority, Portland General Electric, Salt River Project, and Tucson Electric Power; other interviewees include Avista Corporation, Eugene Water & Electric Board, Puget Sound Energy, Sacramento Municipal Utility District, Tacoma Power, and Xcel Energy.

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