Community: Juneau, AK

Total Modelled Emissions: 247,763 mt CO₂e

Direct GHG emissions from stationary (non-transport) combustion of fossil fuels at a facility, such as combustion within boilers, turbines, process heating. These emissions estimate come from modeling based on various datasets for residential, commercial, community, and industrial buildings/facilities.

• Residential sector
• Commercial sector
• Industrial sector

Direct GHG emissions associated with fuel combustion in owned or operated mobile sources, such as on-road vehicles (passenger vehicles, commercial trucks, government fleets) and off-road vehicles (planes, ships) or equipment (air support, construction, agricultural, etc.). These emissions are derived from a number of sources, including downscaled estimates produced with the EPA’s MOVES model.

The MOVES model estimates fuel usage an emissions at the Borough or Census-Area level. To attribute these activities to the communities, these estimates were statistically downscaled using the weighted ratio of distance of roadways, by functional class (i.e.rural, local, interstate), that occured with the geographic boundary of the community, relative to the total annual vehicle flow activity across the respective Borough or Census Area that said community belongs too.

28.16% of the community’s emissions come from the transportation sector

• Transportation sector
• On-road
• Non-road

Direct GHG emissions associated with fuel combustion in electric generation facilities are indicated in this section, including diesel, natural gas, and coal power plants. For communities that participate in Power Cost Equalization (PCE), electric generation information is generally sourced from PCE program data.

The total electricity used from all sources is 405,176.46 MWh.

This table shows scope 1 and scope 2 emissions related to electricity generation.

Energy type	Electricity used	Emissions	Percentage contributed
Hydro	405,176.46 MWh	0.00 mt CO₂e	0.00%

Generally, communities are combusting fuels or generating electricity from sources and assets within the geographic boundaries. Certain communities purchases blocks of electricity from others electric generation outside the geographic scope. Onsite combustion of fossil fuels to convert to electricity via plants within the community boundary will be counted as their stationary combustion, and thus scope 1, whereas purchased from outside of the reporting community boundary, would lead to scope 2 classification. The table above shows an aggregated view of all upstream power generation.

The methodology used in the inventory involved the collection or modeling of energy, fuel, and vehicle data, and the calculation of GHG emissions based on fuel types and uses from different sources and sectors. The inventory used the standard international protocols and methodology to determine metric tons of carbon dioxide equivalent (MTCO₂e) for three greenhouse gases: carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O).

Emissions are generally broken down into Scope 1, 2, and 3. Scope 1 emissions refer to boundary emissions, such as combustion of fuels for use within the community like heating a home or workplace and driving. Scope 2 emissions typically refers to grid supplied energy, such as electricity, heat or steam, either combusted within the boundary and then delivered (in which case it would be Scope 1) or combusted outside the boundary.

Table 1 below provides data on total emissions from the community by sector and source (fuel type) as well as details about each sector and source. This table and the following notes provide the information used to generate the community energy use inventory. The energy use information, combined with the emission factor (metric tons of CO₂ equivalent per unit of energy use) was used to generate the GHG emissions figures found here.

Timescale: A standardized emissions inventory report comprises all GHG emissions occurring during a calendar year. Among others, the United Nations Framework Convention on Climate Change, the Kyoto Protocol, the European Union, The Climate Registry, and the California Climate Action Registry all require GHG inventories to be tracked and reported on a calendar year basis. Additionally to conducting a base year inventory of emissions, a comprehensive inventory of emissions should be completed at regular intervals following the base year to evaluate progress. This report used the 2022 calendar year for the reporting year.

Activity calculation: Calculation-based methodologies were used to quantify the community GHG emissions. This methodology involves the calculation of emissions based on “activity data” and “emission factors.” Activity data represent the relevant measurement of energy use, such as fuel consumption by fuel type (propane, heating oil, diesel, gasoline, jet fuel, etc.) and metered electricity use. These activity data were used in conjunction with an emission factor per unit of fuel, to determine emissions, using the following generalized equation, such that Emissions (CO₂) = Activity Data (MMBTU) x Emission Factor
(CO₂ per MMBTU). MMBtu represents one million British thermal units and is a unit of energy used to compare across different fuel quantities, like diesel vs. electricity - all units of fuels, electricity, and wood have been converted to MMBtu for purposes of comparison.

Emission factors: Emission factors are calculated ratios relating GHG emissions to a proxy measure of activity at an emissions source. We used the emission factors provided in the GHG Accounting Protocol to convert activity data, such as energy usage, into the associated GHG emissions. Whenever emissions values were directly provided, we consulted the source U.S. EPA or the emitters directly to understand data quality. These emission factors are approved by regulatory and research bodies, and were determined by means of direct measurement, laboratory analyses, or calculations based on representative heat content and carbon content. No site-specific emission factors representative of the technology employed (instruments that measure emission concentrations) at specific consuming facilities were used.
For instance, in calculating emissions from stationary combustion using fuel use activity data and default emission factors by fuel type involves the following steps. First, the inventory process determined the total annual consumption of each fuel combusted at community-level sectors, as well as facilities and assets whenever available. Then, determine the appropriate CO₂, CH₄ and N₂O emission factors for each fuel. Finally, calculate each fuel’s CO₂, CH₄ and N₂O emission contributions, and lastly convert CH₄ and N₂O emissions to MTCO₂ equivalent to determine total emissions. CO₂e is an abbreviation for carbon dioxide equivalent, the internationally recognized measure of greenhouse gas emissions. These are reported in the tables. Converting emissions of non-CO₂ gases to units of CO₂e allows greenhouse gases (GHGs) to be compared on a common basis: the ability of each GHG to trap heat in the atmosphere. In this report, non-CO₂ gases have been converted to CO₂e using internationally recognized Global Warming Potential (GWP) factors from Intergovernmental Panel on Climate Change (IPCC) assessment reports. The IPCC developed GWPs to represent the heat-trapping ability of each GHG relative to that of CO₂. For example, the GWP of methane is 21 because one metric ton of methane has 21 times more ability to trap heat in the atmosphere than one metric ton of carbon dioxide. The GWP of nitrous oxide is 310. The CO₂e measure is used worldwide to report the equivalent weight of carbon dioxide in metric tons (MTCO₂e) (1,000 kilograms or 2,205 pounds). The global warming potential from each greenhouse gas is based on the amount of carbon dioxide that would have the same global warming potential measured over a specified time period.