Capital Carbon

Encouraging low-carbon design and use of whole-life costing techniques to future-proof our development activities.

What is Capital Carbon?

Capital carbon refers to carbon and other greenhouse gas emissions associated with the creation, refurbishment and end of life treatment of assets such as buildings and infrastructure. Capital carbon should not be confused with operational carbon, which covers carbon emissions during the operation and maintenance phase of an asset; for information on operational carbon please go to the Energy and Carbon homepage.

Capital carbon relates to those activities that businesses typically fund as capital cost, so the shortened terms ‘CapEx carbon’ or ‘CapCarb’ are sometimes used. Capital carbon includes carbon emissions from the following types of construction / demolition activities.

Carbon emissions associated with other construction-phase aspects may also be considered, so it is always important to be clear and transparent about which activities or aspects have or haven’t been included in a capital carbon assessment.

Why is Capital Carbon important to Network Rail?

In 2013 the government-led Infrastructure Carbon Review (ICR) showed that national infrastructure accounts for over half the UK emissions of carbon and other greenhouse gases (figure 2). 30% of infrastructure emissions are directly attributable to the construction, operation, maintenance, and decommissioning of infrastructure (e.g. capital carbon and operational carbon combined) – these emissions come under the direct control of infrastructure asset owners / managers and their supply chain. The remaining 70% of carbon emissions are attributed to users of the infrastructure, meaning infrastructure asset managers have influence but do not have direct control of these emissions.

Carbon efficiency is a good general indicator of resource efficiency so looking at ways to reduce carbon will often reveal opportunities for other beneficial changes and improvements. Network Rail can benefit directly and indirectly from being carbon efficient in a number of ways.

Direct benefits:

  • Reduction in the use and waste of materials and other valuable resources;
  • Reduction in cost.

Indirect benefits:

  • Contribute to government carbon reduction goals to tackle climate change and leave a positive legacy for future generations;
  • Recognition and enhanced reputation for achievements in sustainable development;
  • Increased investor confidence for infrastructure developments with proven value and sustainability credentials;
  • Promoting collaboration and innovation in the infrastructure value chain to deliver efficient and sustainable outcomes;
  • Attracting and retaining talented, high performing people with the skills and enthusiasm to deliver changes that are of benefit to society, and communities served by infrastructure.

To deliver these benefits Network Rail projects should include capital carbon assessment in their value management activities and processes.  Projects can assess their capital carbon using the Rail Safety and Standards Board (RSSB) Rail Carbon Tool. Use of the tool will enable better decision making with respect to carbon and help the project in achieving the benefits outlined above. Use of the tool will become a requirement for all projects with a value of £1 million or more from March 2019.

Key contacts:

For general enquiries, please email

For specific enquiries, please email Clive Jones.

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