BSI are currently looking for comments on the draft of Publicly Available Specification 2080 which covers the calculation of embodied carbon and operational carbon, or as the PAS calls it, Capital and Operational Carbon for Infrastructure. According to BSI, the objective for PAS 2080 is “to set out a generic, specification for economic infrastructure GHG emission management, founded on currently accepted proven practice and taking account of existing international and sector norms and standards to provide a comprehensive, pragmatic approach to controlling/ reducing, GHG emissions created by infrastructure projects.”
The draft can be viewed and comments made online at http://drafts.bsigroup.com/Home/Details/55613 (registration necessary).
Figure 1: comparing Capital Cost, Embodied Carbon and Capital Carbon, from my thinkstep blog from October 2014.
In my thinkstep blog, I provided an overview of the differences between Embodied Carbon (as assessed using the Global Warming Potential indicator provided in EPD to EN 15804 and building LCA’s to EN 15978) and Capital Carbon, as described in the Low Carbon Routemap and the 2025 Construction Strategy, shortly to be updated with more focus on whole life carbon. As you can see from the diagram above, there were some key differences.
Although both Capital Carbon and Embodied Carbon encompass the environmental impacts associated with manufacturing, transporting and installing construction products, Capital Carbon also took into account the impacts of the design teams working on buildings (assessed to be about 5% of the construction industry impact (see Figure 2 below) and the transport of workers on the construction site (with construction product distribution assessed to be about 10% of construction industry impact). But significantly, for infrastructure, the impacts of waste transport, treatment and disposal were included, but were reported as Operational Carbon rather than Capital Carbon .
Figure 2: Capital Carbon emissions in 2010 (MtCO2e) from Green Construction Board Low Carbon Routemap Report
The good news however, is that PAS 2080 has more closely followed the CEN/TC 350 standards and all impacts associated with construction of infrastructure, including waste treatment of construction waste and the end of life of the asset are now considered as Capital Carbon.
And however Capital Carbon and Embodied Carbon are defined, for construction products, the key piece of information is that the GWP indicator results provided in an EPD to EN 15804 can be used for buildings and infrastructure assessments, and the modular nature of the data provided in the EPD, together with the descriptions of any scenarios used, allows the relevant processes to be considered as required in any assessment, to EN 15978 or PAS 2080, or the CEN/TC 350 framework standard for infrastructure assessments which has just been launched.