I really need to get up to date with my lingo. "Wonkish" is another term I am not overly familiar with. Are those in "Wonkish" circles known as "wonkers"?
The Economist investigate:
The elusive negawatt [Economist]
IN WONKISH circles, energy efficiency used to be known as “the fifth fuel”: it can help to satisfy growing demand for energy just as surely as coal, gas, oil or uranium can. But in these environmentally conscious times it has been climbing the rankings. Whereas the burning of fossil fuels releases greenhouse gases, which contribute to global warming, and nuclear plants generate life-threatening waste, the only by-product of energy efficiency is wealth, in the form of lower fuel bills and less spending on power stations, pipelines and so forth. No wonder that wonks now tend to prefer “negawatts” to megawatts as the best method of slaking the world's growing thirst for energy.
Almost all blueprints for tackling global warming assume that energy efficiency will have a huge role to play. Nicholas Stern devoted a whole chapter to it in the report he wrote on climate change for the British government. In the greenest of futures mapped out by the International Energy Agency, a think-tank financed by rich countries, greater efficiency accounts for two-thirds of emissions averted. The McKinsey Global Institute (MGI), the research arm of the consultancy, thinks that energy efficiency could get the world halfway towards the goal, espoused by many scientists, of keeping the concentration of greenhouse gases in the atmosphere below 550 parts per million.
This long article concludes:
However, no matter what methods governments adopt to encourage energy efficiency, the results may not be as impressive as they imagine. The culprit is something called the “rebound effect”. Falling demand for electricity or fuel brought on by an efficiency drive should lead to lower prices. But cheaper energy, in turn, is likely to prompt greater consumption, undermining at least some of the original benefits. What is more, consumers with lower electricity or fuel bills often put the money they have saved to some other use, such as going on holiday or buying an appliance, which is likely to involve the consumption of fuel and power.
Economists disagree about the size of the rebound effect, which is hard to measure. The British government commissioned two studies of the effect, from two different universities. The first found that it cancelled out roughly 26% of the gains from energy-efficiency schemes; the other put the figure at 37%. Either way, negawatts are worth pursuing. But they are unlikely to satisfy the world's thirst for energy to the extent their advocates assume.