Appendix

GHG Inventory Methodology

Utility Categories

Stationary Combustion

Mobile Combustion

SF6 Fugitives

Purchased Electricity for Resale For all power plant fuel combustion, associated emissions were estimated using factors including fuel carbon content, measured/default heating values, and default emissions factors.

Fuel consumption data was used to estimate CO2 emissions, vehicle mileage data was used to estimate CH4 and N2O emissions.

O‘ahu: As reported in accordance with 40 Code of Federal Regulations (CFR) Part 98 Mandatory Greenhouse Gas Reporting, Subpart DD Electrical Transmission and Distribution Equipment Use Report and Global Warming Potential from the UN IPCC AR5. Maui County and Hawai‘i Island: Excluded from this analysis, expected to be included in future reports.

Supplier-specific approach using site-specific data and Environmental Protection Agency (EPA) Facility Level Information on GreenHouse gases Tool (FLIGHT) database. Assumes all purchased electricity was re-sold.

Stationary Fuel

Mobile Fuel

Employee Commuting Supplier-specific method; includes upstream, midstream & transportation emissions for all fuel types w/ exception of propane.

Supplier-specific method; includes upstream & midstream emissions for biodiesel and clear diesel.

Based on average (e.g., national) data on commuting patterns, adjusting for remote work percentages in 2020 and 2021.

Business Travel Spend-based method in which business travel spend is used to estimate emissions.

American Savings Bank / Pacific Current / HEI Categories

Mobile Combustion

Fugitives Fuel consumption data was used to estimate CO2 emissions, vehicle mileage data was used to estimate CH4 and N2O emissions.

Associated emissions were calculated per Greenhouse Gas Protocol guidance, estimating an upper bound refrigerant leakage rate that is 10% of the total HVAC unit capacity. Office square footage was also used to estimate HVAC capacity.

Purchased Electricity Associated emissions were calculated per EPA guidance using office space electricity consumption and EPA region-specific emissions factors.

CO2e figures have been calculated using global warming potentials from the UN IPCC 5th Assessment Report (AR5).

Sources of emissions factors used in analysis include:  UN IPCC AR5

 EPA Center for Corporate Climate Leadership  EPA eGRID

 EPA Inventory of US Greenhouse Gas Emissions  EPA US Environmentally-Extended Input-Output Models  The Climate Registry  Analysis from Par Refinery, Pacific Biodiesel, and ecoinvent

Endnotes

1 Referred to in "Hawaii Clean Energy Initiative", January 2018, NREL, as “the most aggressive clean energy goals in the nation.”

2 U.S. Energy Information Administration (EIA), EIA Form 861 (2020).

3 City and County of Honolulu Climate Change Commission, Sea Level Rise Guidance (2018).

4 E.g., GHG Protocol World Resources Institute (WRI)/World Business Council for Sustainable Development (WBCSD) Greenhouse Gas Protocol Corporate Accounting and Reporting Standard, ISO 14064 – Greenhouse Gases-Part 1, The Climate Registry Electric Power Sector Protocol, Version 1.0, and Edison Electric Institute and Electric Power Research Institute guidance.

5 A significant portion of our utility GHG emissions were disclosed in our prior two ESG reports. This year’s GHG inventory includes additional Scope 1 and 3 categories for the utility and includes Scope 1 and 2 categories for our non-utility entities. This inventory has been developed alongside a team of experienced third-party advisors. For purposes of this inventory, calculations of previously disclosed utility emissions have been updated to reflect more recent global warming potentials and expanded to include small generation sources.

6 Based on EPA eGRID gross loss factor of 5.6%.

7 Includes whole system (company-owned and independent power producers) generation stack emissions.

8 Some differences may exist between GHG data in this report and GHG data previously disclosed elsewhere (e.g., GHG emissions scorecard), as the utility is in the process of updating its historical data to align with more recent UN IPCC global warming potentials.

9 Biomass combustion emissions of CH4 and N2O are reported and included alongside fossil fuel emissions.

10 National Institute of Building Sciences, Natural Hazard Mitigation Saves (2019).

11 “Transportation emissions have two major sources, ground transportation (cars and trucks) and aviation, with marine transportation contributing minimally to overall emissions. Contributing to more than half of statewide emissions in 2017, transportation emissions are projected to remain relatively stable through 2030,” The Economic Research Organization at the University of Hawai‘i (UHERO), 2021.

12 RPS goals established in 2015 were referred to by the US Dept of Energy as "the most ambitious clean energy target in the country" at the time.

13 Hawaii Greenhouse Gas Emissions Report for 2017: Final Report.

14 As of January 2022.

15 Integrated Grid Planning Forecast.

16 Hawai‘i Wildfire Management Organization.

17 However, Hawai‘i’s average residential electricity bills are helped by lower-than-average electricity usage. Based on 2020 average annual residential customer kWh sales data from the U.S. Energy Information Administration, the average Hawai‘i home used 40% less electricity than the national average.

18 Racially diverse defined as all races/ethnicities that are not ‘White.’

19 Executives includes EEO-1 category 1.1 - Executive/Sr. Level Officials

20 Leaders includes EEO-1 category 1.2 - First/Mid-Level Officials

21 All Workforce includes EEO-1 categories 1.1 - Executive/Sr. Level Officials, 1.2 - First/Mid-Level Officials, 2 - Professionals, 3 - Technicians, 4 - Sales Workers, 5 - Administrative Support Workers, 6 - Craft Workers, 7 - Operatives, 8 - Laborers and Helpers, 9 - Service Workers

22 Racially diverse defined as all races/ethnicities that are not ‘White.’

23 Executives includes EEO-1 category 1.1 - Executive/Sr. Level Officials

24 Leaders includes EEO-1 category 1.2 - First/Mid-Level Officials

25 All Workforce includes EEO-1 categories 1.1 - Executive/Sr. Level Officials, 1.2 - First/Mid-Level Officials, 2 - Professionals, 3 - Technicians, 4 - Sales Workers, 5 - Administrative Support Workers, 6 - Craft Workers, 7 - Operatives, 8 - Laborers and Helpers, 9 - Service Workers

26 Hawaii Greenhouse Gas Emissions Report for 2017: Final Report.

27 Greentech Media: Clean Energy Can Power America’s Economic Recovery.

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