Explanation of Column Headings in the "Detailed Emissions" Table
Facility Total Emissions Reports, which include information submitted annually by specific types of sources of greenhouse gases (GHG), form the basis of the Massachusetts GHG Registry. These reports, which can be accessed from the Massachusetts Greenhouse Gas Emissions Reporting Program page, include a table titled "Detailed Emissions." This table describes the facility's specific activities that generate GHGs, the gases emitted and their global warming potentials, the methods used to develop the emissions report, and information concerning fuel use at the facility where fuel use was the basis for estimating GHG emissions. The content of each column in this table is described below:
- Emitting Activity Name: The name of the emissions source or unit, as reported by the facility.
- Emissions Category: Emissions sources or units are divided into several categories, including stationary and mobile sources, and biogenic fuels. The category that best describes each emission source or unit is identified here. The "scope" listed in this column is not directly relevant for the Massachusetts GHG reporting program, but is used in The Climate Registry's voluntary program to distinguish "direct" emissions (e.g., emissions from entity-owned or controlled sources) from other reported emissions (e.g., emissions from generating electricity used at a facility, or emissions from employee commuting).
- Emitting Activity: The type of emissions source or unit. For example, this column may specify that the source or unit is a boiler, a particular type of motor vehicle, or an air conditioner.
- Greenhouse Gas: The specific greenhouse gas emitted, such as carbon dioxide (CO2) or methane (CH4).
Amount (metric tons): The amount of the greenhouse gas emitted in the reporting year (not adjusted for the global warming potential).
- Total CO2e (metric tons): The amount of the greenhouse gas, adjusted for the global warming potential. Global warming potentials are factors used to account for the fact that greenhouse gases differ in the amount of warming that result from emitting a given amount of gas. These factors allow a facility to express its total GHG emissions as "carbon dioxide equivalents" (CO2e), and therefore to calculate its total potential for global warming from its emissions of several types of gases.
- Calculation Methodology: The method used by the facility to calculate emissions. For example, facilities may use default emission factors or a custom formula, or may report pre-calculated emissions totals. "CEMS" means that the emissions were measured directly with a continuous emissions monitor, and were not calculated using fuel consumption data.
- Factor Source: This column identifies the reference document that includes emission factors and other variables used to calculate emissions. Reference documents are available at: http://www.theclimateregistry.org/resources/protocols/general-reporting-protocol/
- Fuel: Where the activity's GHG emissions were calculated on the basis of fuel use, this column identifies specific characteristics of the fuel. Characteristics may include the heat content, fuel type, etc. At this time, the report does not identify the specific fuel (e.g., coal, oil, gas, etc.). However, in most cases, the fuel can be deduced by interpreting the information in this column and the units of measure in other columns. For example, if "scf" (standard cubic feet) appears as a unit in any column, then the fuel is natural gas, or another gaseous fuel such as landfill gas. Fuels are listed in the "Submission Reports" available in the "Detailed Information" section of the Registry.
- Amount: The quantity of fuel combusted during the reporting year, if applicable.
- Emission Factor: Emission factors are standard values that are used to calculate emissions using fuel consumption or other quantitative information. This column identifies the specific emission factor that was used to quantify emission from the source or unit, if applicable.
- Heat content: The heat content of a fuel is the energy content contained in a given amount of fuel. This column includes the heat content that was used to quantify emissions from the source or unit, if applicable.
- Oxidation factor: In many cases, an oxidation factor is used to account for cases in which a small fraction of the fuel supplied to a combustion unit is not actually oxidized. This column includes the oxidation factor that was used to quantify emissions from the source or unit, if applicable.
- Comment: This column contains comments provided by the facility.
See Massachusetts Greenhouse Gas Emissions Reporting Program for additional information, including links to the Massachusetts GHG Registry, which contains Facility Total Emissions Reports, and the General Reporting Protocol (GRP), which includes additional explanations of the information listed above.