1. Carbon Footprint

2. Definition
is a measure of the impact our activities have on the environment, and in particular climate change. It relates to the amount of greenhouse gases produced in our day to day lives through burning fossil fuels for electricity, heating and transportation etc. The carbon footprint is a measurement of all greenhouse gases we individually produce and has units of tonnes (or kg) of carbon dioxide equivalent.

3. Types

4. A carbon footprint is made up of the sum of two parts, the primary footprint (shown by the green slices of the pie chart) and the secondary footprint (shown as the yellow slices).
The primary footprint 
is a measure of our direct emissions of CO2 from the burning of fossil fuels including domestic energy consumption and transportation (e.g. car and plane). We have direct control of these.

5. 2.The secondary footprint 
is a measure of the indirect CO2 emissions from the whole lifecycle of products we use - those associated with their manufacture and eventual breakdown. To put it very simply – the more we buy the more emissions will be caused on our behalf.

6. Calculating a carbon footprint can be a valuable first step towards making quantifiable emissions reductions. This in turn can lead to long term financial savings as well as reducing climate-change impact.

7. An organisation, for example, that wants to reduce its climate change impact will usually first calculate its carbon footprint and then identify areas of its operations where emissions reductions can be made. Emissions reductions (also known as ‘offset’) are sold in tonnes of CO2 equivalent and can come from a range of projects such as renewable technologies, energy efficiency projects, land-use change projects and methane capture.

8. Measurements
There are many reasons for calculating the carbon footprint but they can be summarised as follows: To establish a true and fair account of CO2e. To simplify and reduce the costs of associated with CO2e.

9. Measurements
To provide Management with information that can be used to build an effective strategy to enable the preparation of a carbon management programme. To provide information that facilitates participation in voluntary and mandatory CO2e reduction programmes.

10. Measurements
To reduce the effects of climate change, carbon output could be reduced by reducing GHG production as following step:
Calculate a carbon footprint to understand the amount of greenhouse gas emissions.
Determine the ideal carbon footprint
Identify the source of the most significant carbon dioxide emissions

11. Measurements
Reduce carbon dioxide emissions by starting with the most significant. Carbon footprint calculations consists of two main components know as direct and indirect emissions. This distinction is important as it allows for emissions to be calculated for a specific entity, or company and provides a mechanism to ensure that double accounting does not occur.

12. The steps needed to work out a carbon footprint are different depending on whether the subject is an organisation or a product.
The basic steps required to calculate a carbon footprint for an organisation are as follows:
1. Establishment of the assessment boundaries:
• Organisational
• Operational
• Greenhouse gases
2. Collection of data.
3. Calculation of emissions using appropriate emissions factor

13. Examples
Ex 1) Carbon footprint of a Company with 5 offices Assessment the greenhouse gas boundary includes CO2, CH4 and N2O emissions arising from fuel combustion and CH4 emissions from waste disposal to landfill. Sometimes companies may choose to conduct a simplified assessment concentrating only on CO2 emissions.

16. Example 1
For organisations a useful measure can be average annual emissions per employee

17. Examples
Ex 2) Carbon Footprint of The Times Newspaper Assessment Analysis

18. Example 2

19. Example 2
Calculation of emissions

20. Ex3
For WWTP shown below, evaluate the Carbon Footprint.

21. GHG emission from an activated sludge can be classified into six categories such as: 1) Greenhouse gases emission from biological treatment process. 2) Greenhouse gases emission caused by the energy consumption within the wastewater treatment plants: CO2 emission from biogas and fossil fuel combustion for energy generation. 3) Material usage: chemical for on-site usage. These chemicals will be accounted for GHGs emission.

22. 4) Degradation of biosludge/solid digester
4) Degradation of biosludge/solid digester. Biosludge will dispose to the landfill. 5) Degradation of remaining constituents in the effluent. 6) GHG emissions from Solid waste transportation and disposal.