George Monbiot’s book Heat (reviewed here) includes a brief discussion on the difference between efficiency and reduction. Given that eco-efficiency is one of the buzzwords of sustainability, I want to highlight his discussion, as it seems to me to be very important for greens to be aware of the problem he outlines.
Monbiot notes that if a new consumer gadget or a new industrial production process or a refitted home uses 30% less energy than previously, then we might assume that 30% of the previous energy consumption has been saved. Unfortunately, due to some very inconvenient side-effects of eco-efficiency, this is not necessarily the case.
These side effects operate on two levels.
The first effect is explained by the ‘Khazzoom-Brookes Postulate’. This postulate suggests that as energy efficiency in industrial production improves, business costs are lowered and money becomes available for investment in other areas. At the same time, energy intensive industrial processes that were previously not financially viable become a lot more attractive. So the money made available by energy efficiencies can lead to expanded production, possibly even to an actual increase in overall energy consumption (p.61). Monbiot acknowledges that this is a rather controversial proposition, but he finds some economic historical evidence for such effects.
Secondly, we have the Rebound Effect. This works as follows: if we insulate our homes effectively, our domestic heating bills go down. As a result we are tempted to turn up the heat to make the home more cosy. As car engines have become more efficient, we can afford all sorts of extras such as air conditioning, electric windows, etc (p.62).
Overall, then, some, many or even all of the gains of eco-efficiency can easily be lost in expanded production and more luxurious consumption. Apparent techno-managerial solutions do not in themselves provide the complete answer to ecological problems: they merely provide opportunities, and conscious changes in our behaviour are also needed for these opportunities to be fulfilled.
George Monbiot (2007) Heat (2nd edition). London: Penguin Books.