Appendix A — Supplementary data

A.1 Emissions factors

Note for solid waste, the global warming potentials used to calculate CO2e are sourced AR4, not AR5, like the rest of our inventory. However, documentation for the EPA WARM tool (USEPA 2019), indicates that the differences in total CO2e emissions is negligible.

All EPA Emission Factor Hub values were pulled from an Excel workbook downloaded from the EPA website. Values were processed in epa_ghg_factor_hub.R.

Table A.1: Electricity emission factors. 2021 EPA GHG Emission Factor Hub, EPA eGRID2019, February 2021.
eGrid Subregion Grid Output GHG lb GHG per MWh
MROW (MRO West) Total output CO₂ 995.80000
MROW (MRO West) Total output CH₄ 0.10700
MROW (MRO West) Total output N₂O 0.01500
MROW (MRO West) Total output CO₂ 1821.84000
MROW (MRO West) Total output CH₄ 0.02800
MROW (MRO West) Total output N₂O 0.03071
Table A.2: Stationary combustion emission factors. 2021 EPA GHG Emission Factor Hub, Federal Register EPA; 40 CFR Part 98.
Fuel type GHG GHG Quantity Unit Value
Natural Gas
Natural Gas CO₂ Kilograms mmBtu 53.06000
Natural Gas CH₄ Grams mmBtu 1.00000
Natural Gas N₂O Grams mmBtu 0.10000
Natural Gas CO₂ Kilograms scf 0.05444
Natural Gas CH₄ Grams scf 0.00103
Natural Gas N₂O Grams scf 0.00010
Petroleum Products
Kerosene CO₂ Kilograms mmBtu 75.20000
Kerosene CH₄ Grams mmBtu 3.00000
Kerosene N₂O Grams mmBtu 0.60000
Kerosene-Type Jet Fuel CO₂ Kilograms mmBtu 72.22000
Kerosene-Type Jet Fuel CH₄ Grams mmBtu 3.00000
Kerosene-Type Jet Fuel N₂O Grams mmBtu 0.60000
Propane CO₂ Kilograms mmBtu 62.87000
Propane CH₄ Grams mmBtu 3.00000
Propane N₂O Grams mmBtu 0.60000
Table A.3: Solid waste emission factors. 2021 EPA GHG Emission Factor Hub, EPA WARM version 15, November 2020.
Material Metric tons CO₂e per short ton material
Recycled
Mixed Recyclables 0.09
Mixed Organics NA
Mixed MSW NA
Landfilled
Mixed Recyclables 0.68
Mixed Organics 0.48
Mixed MSW 0.52
Combusted
Mixed Recyclables 0.11
Mixed Organics 0.05
Mixed MSW 0.43
Composted
Mixed Recyclables NA
Mixed Organics 0.17
Mixed MSW NA

A.1.1 Transportation emissions rates

We can calculate gross emissions rates in grams emitted per vehicle mile traveled for each county by combining the historical VMT (Section 2.2.2), VMT forecasts, (Section 2.2.3), compiled historical annual emissions (Section 2.2.1), and emissions forecasts (Section 2.2.3.2).

These emissions rates are comprehensive, in that they do not account for differences in vehicle or fuel type.

Compilation provided in calc_gross_emissions_rates.R.

Figure A.1: Gross emissions rates, 2010-2022

The Council does not currently run MOVES for counties outside the core metro region. For collar counties (Sherburne, Chisago, Pierce, St. Croix), we calculated the change in emissions from 2022 to 2050 in the most similar core county and applied this value to 2022 county-specific emissions.

Future work will complete MOVES runs for all counties, including the 4 collar counties.

Table A.4: Forecasted annual gross emissions rates by county, 2050
County VMT data source Emissions data source Grams CO₂e per vehicle mile traveled
Anoka RTDM RTDM and EPA MOVES4 253.814
Carver RTDM RTDM and EPA MOVES4 254.754
Chisago RTDM Expected change in emissions in similar county 472.948
Dakota RTDM RTDM and EPA MOVES4 253.399
Hennepin RTDM RTDM and EPA MOVES4 255.698
Pierce RTDM Expected change in emissions in similar county 513.201
St. Croix RTDM Expected change in emissions in similar county 549.148
Ramsey RTDM RTDM and EPA MOVES4 251.567
Scott RTDM RTDM and EPA MOVES4 255.913
Sherburne RTDM Expected change in emissions in similar county 390.802
Washington RTDM RTDM and EPA MOVES4 256.877

A.2 Global Warming Potential (GWP)

The Global Warming Potential (GWP) was developed to allow comparisons of the global warming impacts of different gases. Specifically, it is a measure of how much energy the emissions of 1 ton of a gas will absorb over a given period of time, relative to the emissions of 1 ton of carbon dioxide (CO2). The larger the GWP, the more that a given gas warms the Earth compared to CO2 over that time period (USEPA 2023).

Across all sectors, we used the GWP values established in the Intergovernmental Panel on Climate Change (IPCC) 6th Assessment Report (AR6), Table 7.SM.7 (IPCC 2023). We processed these values in global_warming_potential.R.

Table A.5: Global Warming Potential (GWP) values
Gas 100-year GWP value Source
CO₂ 1.0 IPCC AR6 (2021)
CH₄ 27.9 IPCC AR6 (2021)
N₂O 273.0 IPCC AR6 (2021)
CF4 7380.0 IPCC AR6 (2021)
HFC1 164.0 IPCC AR6 (2021)
SF₆ 24300.0 IPCC AR6 (2021)
NF₃ 17400.0 IPCC AR6 (2021)
1 Hydrofluorocarbon-152a, Difluoroethane

A.3 Geographic data

Geographic data were processed in cprg_geography.R.

A.3.1 Counties

County data was pulled using {tigris}, an R package that downloads TIGER/Line shapefiles from the US Census Bureau (Walker 2023). 2021 geographies for Minnesota and Wisconsin were pulled, combined, and saved.

Table A.6: County geography metadata
Column Class Description
geoid character County GEOID. 5 digit.
county_name character County name
county_name_full character Full county name
state_name character Full state name
statefp character State FIPS code
state_abb character Abbreviated state name
cprg_area logical Whether county is included in the CPRG area
geometry sfc_MULTIPOLYGON Simple feature geometry

Additionally, population estimates were obtained from the American Community Survey 5-Year estimates (2017-2021) using {tidycensus} (U.S. Census Bureau 2021).

Table A.7: County population metadata
Column Class Description
geoid character Five digit county GEOID
county_name character County name
state_name character Full state name
state_abb character Abbreviated state name
population numeric Total county population estimate (persons)
population_data_source character Population estimate data source

A.3.2 Cities

Minnesota cities, townships, and unorganized territories were imported from Minnesota Geospatial Commons (MnDOT 2023).

Wisconsin cities, towns, and villages were imported from Wisconsin’s Legislative Technology Services Bureau (Wisconsin Legislature 2023).

Data from both states was then combined and filtered to include only the workplan area counties.

Table A.8: City geography metadata
Column Class Description
gnis character Geographic names information system (GNIS) identifier. 8 digit.
ctu_name character CTU name
ctu_class character CTU class (either CITY, TOWNSHIP, or UNORGANIZED TERRITORY
geoid_wis character Wisconsin geographic identifier
geometry sfc_MULTIPOLYGON Simple feature geometry
thrive_designation character Community designation in Thrive 2040
imagine_designation character Community designation in Imagine 2050
county_name character County name
state_name character Full state name
statefp character State FIPS code
state_abb character Abbreviated state name
cprg_area logical Whether county is included in the CPRG area