17th July 2013 Montreal, Canada
Life Cycle Assessment: from cold water washing to cotton bags (by guest blogger Roland Clift)
This post is written by Roland Clift , Emeritus Professor of Environmental Technology in the Centre for Environmental Strategy at the University of Surrey, who was keynote speaker at the Montreal conference on Social – Life Cycle Assessment held in Montreal last May.
Life Cycle Assessment – LCA for short – is the term given to a particular approach to evaluating the environmental impacts of providing a product or a service. Its value lies in evaluating all the resources used and the emissions released along the complete supply chain, and assessing their significance to build up the environmental profile of the product.
Although LCA is not widely recognised, it is already widely used. One of the first applications was to the mundane matter of washing clothes. LCA showed that one of the biggest causes of environmental impact was heating water for the wash. This realisation prompted the development of low-temperature detergents – which could be even more environmentally benign if only people could be persuaded to turn down the wash temperature!
This also illustrates another aspect of trying to develop environmentally-friendly products: people have to be persuaded to prefer them and to use them properly. “Carbon footprint” labels are starting to appear on many products, with the intention of helping consumers to include environmental performance in their purchasing choices. Labels like the carbon footprint are necessarily based on life cycle assessment.
LCA can sometimes throw up surprising conclusions. For example, it is currently fashionable to use cotton rather than plastic shopping bags, on environmental grounds. LCA tells us that cotton bags have a big environmental footprint, mainly due to the water and agrochemicals used in growing cotton, so you have to use the cotton bag way more than 100 times before it beats the plastic bags on environmental grounds. That’s provided the plastic bags are disposed of properly. The problem is that people just discard them, so that they can end up, for example, in the oceans. Shopping bags are a human behaviour problem first!
Life cycle assessment is particularly helpful in managing food supply chains: most of the main retailers use LCA as a basis for managing their purchases, selecting their suppliers and helping them to improve their environmental performance. Some food products also show a different kind of label, based on “ethical sourcing”; the Fair Trade label and logo is probably the most widely recognised. Labels like Fair Trade focus not on environmental performance but on how far the economics in the supply chain provide benefits to the least privileged workers, usually the farmers involved with producing the food in the first place.
So can we find a way of applying life cycle assessment to show the socio-economic benefits as well as the environmental impacts of a supply chain? Attempts are being made to develop a systematic tool for this purpose; it is called Social Life Cycle Assessment. The approach needs to be standardised and widely accepted because consumers need to be sure that companies making claims of responsible social performance can be trusted – in much the same way as award of the Fair Trade label is carefully certified.
Last May, a conference on S-LCA was held in Montréal on 6th and 7th May 2013, attended by a academics and “practitioners”, hosted by the Interuniversity Research Centre for the Life Cycle of Products, Processes and Services (CIRAIG) at École Polytechnique de Montréal, to discuss where we have got to and what needs to be done now to develop S-LCA. So, somewhere down the line, you should be able to look out for consumer products, not just food, carrying a label to tell you that “ethical supply” really means something.