Fortunately, energy is only one of the ingredients behind the services that are so beneficial, the other is the equipment - the furnaces, lights, automobiles, etc. And experience has shown that the use of increasingly sophisticated equipment can provide more of these services with less energy. That is with greater energy efficiency. Much of the challenge in creating a sustainable energy system lies in how technological achievements can be put to use faster, be more broadly disseminated and how energy user behaviour adapts. Since the oil shocks of the 1970s, energy efficiency has improved considerably in response to energy price increases and supply uncertainties, government policies, and independent technology improvements.
Further gains are still possible in all economies.
But, large-scale energy efficiency improvements can be obtained neither easily nor quickly. Concerted policy actions to foster investment in improved equipment, buildings and infrastructure and to cultivate persistent attention to energy-consuming behaviour are needed. Unfortunately, opportunities can be easily lost for long periods. Each time old capital stock is replaced or refurbished, or new stock is put in place, a ripe opportunity to improve energy efficiency presents itself. When such opportunities are ignored, energy wastage is perpetuated for a long time, because of the slow turnover rate of most capital stock.