Greenhouse Gas Emissions Inventory Tool
This tool assists in the process of compiling a greenhouse gas (GHG) emissions inventory for a province or municipality
What is a GHG Emissions Inventory?
A greenhouse gas (GHG) emissions inventory is a list of GHG emission sources and the associated emissions of each of the sources. GHG emissions inventories are undertaken for a specific geographically defined area (e.g. a country or a subnational area such as a province or municipality) for specific time periods (e.g. a specific year).
To understand whether GHG emission reduction targets are being met, GHG emissions need to be measured annually and then compared to the GHG emissions of previous years. By comparing these annual GHG emissions inventories, a province or municipality can see if its emissions are increasing or decreasing.
The key source of information used in this guide for compiling a GHG Emissions Inventory for a subnational area is the 2021 Greenhouse Gas Protocol – Global Protocol for Community-Scale Greenhouse Gas Emission Inventories: An Accounting and Reporting Standard for Cities Version 1.1 (GPC). The GPC is a globally recognised framework that is designed to promote best practice GHG accounting and reporting.
What are the boundaries of a GHG Emissions Inventory?
The boundaries of a GHG Emissions Inventory include the geographic area and time period, and the greenhouse gases and sources of emissions that are coved by a GHG Emissions Inventory. The boundaries of a GHG Emissions Inventory allows a municipality (or province) to understand where the emissions are coming from and where it can take action to reduce emissions.
The geographic area will be the spatial boundaries of the province/municipality undertaking the GHG emissions inventory. As far as possible, the province/municipality must maintain the same geographic boundary for its GHG emissions inventory for consistent GHG emissions inventory comparisons over time.
A GHG emissions inventory must cover a continuous period of 12 months. This period should ideally align to a calendar year or a financial year. The intention of the province/municipality should be to update their GHG emissions inventory annually, with the most recent data available, to track trends in its GHG emissions over time.
Greenhouse Gases (GHGs)
Emissions of the following GHGs should be accounted for in a GHG emissions inventory (as currently required under the Kyoto Protocol): carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), and nitrogen trifluoride (NF3).
Sources of GHG Emissions
As per the GPC, GHG emissions are classified into the following sectors:
- Stationary Energy
- Industrial Processes and Product Use (IPPU)
- Agriculture, Forestry, and Other Land Use (AFOLU)
- Other (This sector is optional as it relates to any other emissions occurring outside the geographic boundary of the province/municipality as a result of provincial/municipal activities.)
A breakdown of these sectors and their sub-sectors (from page 35 of the GPC) is provided on the right.
Activities taking place within a province/municipality can generate GHG emissions that occur inside the provincial/municipal boundary as well as outside of this boundary. To distinguish between these, the GPC groups emissions into three categories, called “scopes”, based on where the emissions occur. All GHG emissions fall into one of these three scopes
These are emission that physically occur within the boundary of the province/municipality. An example is the burning of coal in a particular industry located within the province.
These are emissions that are imported into the province/municipality by grid supplied electricity or heating
These are emissions that occur outside the provincial/municipal boundary but are as a result of activities taking place within the province/municipality. An example of Scope 3 emissions are emissions from waste generated in the province/municipality that are processed outside of the province/municipality
For each of the three scopes, some examples of applicable emissions (from page 36 of the GPC) are shown below.
What are the key steps involved in developing a GHG Emissions Inventory?
The GPC has two GHG emissions inventory reporting levels called “BASIC” and “BASIC+” These two reporting levels differentiate on data availability and the calculation methodologies used. The BASIC+ level has more comprehensive coverage of emissions sources.
The Greenhouse Gas Protocol – Global Protocol for Community-Scale Greenhouse Gas Emission Inventories: An Accounting and Reporting Standard for Cities Version 1.1 provided a detailed guide for developing a GHG Emissions Inventory.
The BASIC reporting level covers Scope 1 and Scope 2 emissions from Stationary Energy and Transportation, as well as in-boundary generated waste. Specifically, the BASIC reporting level covers
- All Scope 1 emissions from Stationary Energy sources (excluding energy production supplied to the grid, which shall be reported in the scope 1 total)
- All Scope 1 emissions from Transportation sources
- All Scope 1 emissions from Waste sources (excluding emissions from imported waste, which shall be reported in the Scope 1 total)
- All Scope 2 emissions from Stationary Energy sources and Transportation
- Scope 3 emissions from treatment of exported waste
The BASIC+ reporting level reflects more challenging data collection and calculation processes, and additionally includes emissions from IPPU, AFOLU, transboundary transportation, and energy transmission and distribution losses. The sources covered in BASIC+ also align with sources required for national reporting in IPCC Guidelines.
The steps outlined below follow the BASIC reporting level. The province/municipality should aim to cover all GHG emissions for which reliable data are available.
Step 1: Setting the Boundaries
Under Step 1, the following should be completed:
- Describe the geographic boundaries of the province/municipality, including a map and the rationale used for selecting the geographic boundary
- Outline of the activities included in the inventory, and if other Scope 3 are included, a list specifying which types of activities are covered
- Write down any specific exclusion of required sources, facilities, and/or operations, along with a clear justification for their exclusion
- Write down the continuous 12-month reporting period covered.
- Write down the reporting level chosen (BASIC or BASIC+)
- Provide an overview of the reporting city, including total geographic land area, resident population, and GDP
Step 2: Securing the necessary data
Under Step 2, the following data shall be secured:
- All Scope 1 emissions from Stationary Energy sources and Transportation sources
- Solid Fuel Combustion
- Solid fuel data can be collected from the South African Greenhouse Gas Emissions Reporting System (SAGERS)
- A formal request needs to be submitted to DFFE to get this data
- The data does not include residential or small-scale commercial solid fuels such as coal used at a household level.
- Liquid Fuel Combustion
- Liquid fuels data are provided at a magisterial district level by the DMRE
- These magisterial district boundaries may need to be aligned with the current district municipal boundaries using a proportional spatial allocation between the two datasets
- Solid Fuel Combustion
- All Scope 1 emissions from Waste sources
- Solid Waste Disposal
- Solid waste sector GHG emissions can be modelled based on the IPCC’s waste model from Volume 5: Chapter 3 of the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, which provides national default values for waste generation rates and a excel modelling tool
- The solid waste data are modelled using population number and GDP assumptions, and the split between Municipal Solid Waste (MSW) and Industrial Waste
- Wastewater Treatment
- Wastewater sector GHG emissions can be modelled based on the IPCC’s waste model from Volume 5: Chapter 3 of the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, which provides national default values for waste generation rates and a excel modelling tool
- The wastewater data are modelled using population number and GDP assumptions
- Solid Waste Disposal
- All Scope 2 emissions from Stationary Energy sources and Transportation sources
- Electricity Sales
- Electricity Sales data by province are provided by Statistics SA per province over multiple years
- These data are currently provided at the provincial level. Municipalities would need to access the electricity sales date for their own area either through their Electricity Sales Department and/or from Eskom.
- Electricity Sales
- GHG Emissions factors
- These are factors that convert activity data into GHG emissions data
- To standardise reporting, source data needs to be multiplied by an emissions factor to convert all data to Gigagrams of carbon dioxide equivalent (Gg CO2e) (1 Gigagram = 1 million kilograms)
- GHG Emission factors may be sourced from the IPCC’s Emission Factor Database
- Where possible, South African-specific emission factors should be used, for example:
- Stationary and Non-stationary Energy Emission Factors: Taxation Laws Amendment Act (No. 34 of 2019))
- Electricity Sales Emission Factor: Eskom Annual Reports
- The Global Warming Potential of the different GHG needs to be taken into account
Step 3: Calculating the estimated GHG emissions for the inventory
The Greenhouse Gas Protocol – Global Protocol for Community-Scale Greenhouse Gas Emission Inventories: An Accounting and Reporting Standard for Cities Version 1.1 provided a detailed guide for calculating GHG emissions by emissions source (See chapters 5 to 8).
Examples of GHG Emissions Inventories
Some examples of existing GHG Emissions Inventories for different spheres of government in South Africa include:
- South Africa | South Africa’s National GHG Inventory Report 2017 | Published in August 2021, this is South Africa’s 7th National GHG Inventory Report. It covers the time period: 2000 to 2017.
- Western Cape Province | Western Cape Greenhouse Gas Inventory Report | Published in January 2013, this GHG Inventory is for 2009.
- EThekwini Municipality (Durban) | eThekwini Greenhouse Gas Emissions Inventory 2019 | Published in 2021, this GHG Inventory is for 2019.
- Cape Town | City of Cape Town Climate Change Action Plan | Published in 2021, this GHG Inventory is for2018.
- Johannesburg | City of Johannesburg Climate Change Action Plan | Published in 2021, this GHG Inventory is for 2016.