Daly City's Green Vision - City of Daly City

A.1.3 Types of Emissions
The greenhouse gases inventoried in this report are described in Section 2.1 As described in LGOP, emissions from
each of the greenhouse gases can come in a number of forms:
Stationary or mobile combustion: These are emissions resulting from on-site combustion of fuels (natural gas,
diesel, gasoline, etc.) to generate heat, electricity, or to power vehicles and mobile equipment.
Purchased electricity: These are emissions produced by the generation of power from utilities outside of the
jurisdiction.
Fugitive emissions: Emissions that result from the unintentional release of greenhouse gases into the atmosphere
(e.g., leaked refrigerants, methane from waste decomposition, etc.).
Process emissions: Emissions from physical or chemical processing of a material (e.g., wastewater treatment).
A1.4 Quantifying Emissions
Emissions can be quantified two ways:
Measurement-based methodologies refer to the direct measurement of greenhouse gas emissions (from a
monitoring system) emitted from a flue of a power plant, wastewater treatment plant, landfill, or industrial facility.
This methodology is not generally available for most types of emissions and will only apply to a few local
governments that have these monitoring systems.
The majority of the emissions recorded in the inventory can be and will be estimated using calculation-based
methodologies to calculate their emissions using activity data and emission factors. To calculate emissions, the
equation below is used:
Activity Data x Emission Factor = Emissions
Activity data refer to the relevant measurement of energy use or other greenhouse gas–generating processes such as
fuel consumption by fuel type, metered annual energy consumption, and annual vehicle mileage by vehicle type.
Emissions factors are calculated ratios relating emissions to a proxy measure of activity at an emissions source (e.g.,
CO 2 generated/kWh consumed). For a list of common emissions calculations see Table 2.2.
The guidelines in LGOP are meant to provide a common method for local governments to quantify and report
greenhouse gas emissions by using comparable activity data and emissions factors. However, LGOP recognizes that
local governments differ in how they collect data concerning their operations and that many are not able to meet the
data needs of a given estimation method. Therefore, LGOP outlines both “recommended” and “alternative” methods
2005 Daly City Government Operations Greenhouse Gas Emissions Inventory III