Iso 14064

Operating a greenhouse gas accounting system should be the corner stone of every corporate climate change strategy. ISO 14064 is one of the internationally recognised corporate management systems for greenhouse gas accounting. There is one other widely accepted system, which is the Greenhouse Gas Protocol, developed by the World Resource Institute and the World Business Council for Sustainable Development. In addition to these to systems the Intergovernmental Panel on Climate Changed has pubished guidance on the design and operation of national GHG inventories.

The key elements to greenhouse accounting are:

• setting up a greenhouse gas emmissions inventory
• identifying the main contributors to greenhouse gas emissions
• develop and implement an improvement programme

key challenges

Boundary of the organisation

Uncertainty
Certain contributors to the greenhouse gas emissions of an organisation are relatively straightforward to quantify. An example of these are the carbon emissions from the use of energy to heat and operate buildings. Energy bills and energy usage are well recorded in most organisations and standard conversation factors can be used to calculate the carbon emissions frome these figures.

It will be more difficult to split the total energy use in its sources. Save from coninuous monitoring of each piece of energy using equipment, certain assumptions will have to be made. For instance even in its basic form the amount of carbon emissions that should be attributed to a particular piece of equipment is often based on an assumption of the daily operation time. Even this assumptions introduces an element of uncertainty in the final figure.

The uncertainty depends on a number of elements. Firstly, it depends on the scope of the GHG accounting system. If the scope is restricted to the direct emissions arising form the organisations activities, it is easier to control the data and therefore reduce the uncertainty. When an organisation chooses to include the emissions that are embedded within the materials they use, an additinal level of complexity will be introduced and the uncertainty of data may become an important factor. Other elements that influence the uncertainty of data include the complexity of the system or organisation that is involved and the state of scientific knowledge regarding the greenhouse emissions that are associated with materials and process.

Documenting the assumptions, methodologies and uncertainties witin the greenhouse gas accounting system is an essential element of each GHG accounting system.