Embodied carbon is the next hot topic
The UK-GBC’s recent seminar on this topic at the Building Centre in London was packed out – close to 250 delegates and almost 20% of them architects. I attend many events and I haven’t seen one as buzzy as this one since the UK-GBC ‘s panel discussion on the Merton rule which now seems like ancient history. This is the second event I’ve attended on embodied energy in the past month (the other was a talk by Ramboll’s Simon Smith at Ted Cullinan’s office - part of the practice’s excellent monthly sustainability talks– which had a largely timber focus).
We’ve been hearing for some time that as a building’s operational C02 emissions are reduced, the relative importance of embodied carbon increases. Where do we go from here? Many have talked about ‘whole life costing’ and ‘life cycle analysis’ but few have offered tools that could be used by any but the most avid number cruncher.
Sturgis Associates’ carbon profiling approach, featured in AJ 26.03.09, has now been further developed and published in an imminently readable report by RICS Research called Redefining Zero, which can be downloaded here.
The report predicts that within ten years the typical split between embodied (red) and operational carbon (blue) for various building types will shift completely:
What I find interesting about carbon profiling is that it takes into account the life span of different building components so it introduces a time component into the calculation.
Carbon profiling methodology is clearly explained and applied to a case study of Arup Associates’ Ropemaker Place, a 20-storey BREEAM Excellent office block in the City completed in May 2009. This research, commissioned by British Land’s Sarah Cary who was also on the panel, shows that embodies carbon makes up more than half of Ropemaker’s carbon emissions.
The next challenge is creating statutory incentives for reducing embodied carbon. Simon Cox of ProLogis described a recent project where planners were willing to reduce the renewables requirement in light of a sustainability strategy which had addressed embodied carbon. Guy Battle of dcarbon8 (and now Deloitte) remarked that the day will come Part L incorporates embodied carbon. Simon Sturgis noted that BREEAM awards less points for retaining a concrete frame than for putting bat boxes on a building.
Discussions of embodied energy are in early days, but they are going to ramp up quickly. The creation of a UK-GBC task force on this issue would be a sure sign of more to come.
Filed under: Energy
Embodied carbon will certainly be one of the next hot topics, perhaps sooner than many may expect…
The University of Bath Inventory of Carbon & Energy (ICE) database of building materials is a great resource for quick comparisons and for more detailed digging:
http://www.bath.ac.uk/mech-eng/sert/embodied/
This is a good insight into what is yet to come. It certainly makes sense that as buildings become more efficient, the embodied element becomes more significant. One of the main challenges is the richness CO2 data as most formulae for products are still quite generic at this point.
We have built a system for calculating embodied CO2e on building projects and include as much data as we can. Although, we are constantly adding more information to our aggregation platform as it becomes available. More info can be found here:
http://www.carboncalculated.com/products/construction_cc
Indeed, it’s obvious that embodied carbon will become more and more important as time passes. The Empty Homes Agency did some work on whether it is preferable to build new homes or refurbish existing homes (a project I worked on) and I’ve done a bit of an update analysis which looks at the benefit when moving towards zero carbon homes. http://ococarbon.wordpress.com/2010/05/31/refurbish-or-replace/
It shows that so long as refurbishment is done with an attempt to minimise in-use emissions, it is still preferable to refurbish and retain the embodied carbon of the structure. On the other hand, if the refurbishment is not done with decreasing emissions in mind, new build may well be a better option.
Of course we need both, and these are only back of an envelope type calculations. A more robust way of assessing the embodied carbon (and other impacts) of buildings, as well measuring their value is greatly needed.