Rich and developing countries alike have woken up to the reality that cheap and plentiful energy can no longer be taken for granted and that growing demand is harming the environment and quality of life.
Efforts to reduce energy consumption or increase the use of renewable sources are hampered by the fact that economic growth brings higher energy needs and it is still more expensive to produce power from the sun, wind and waves than from fossil fuels.
Yet governments do agree that using energy more efficiently will go some way toward ensuring that the climate isn't harmed by efforts to raise living standards worldwide.
Leaders of 16 major economies, including the United States, Japan, Germany, the U.K., China, Brazil, India and Russia, pledged in a joint statement in July 2008 to "improve significantly energy efficiency, a low-cost way to reduce greenhouse gas emissions and enhance energy security."
In July 2009, the G8 group of developed economies pledged to reduce their greenhouse gas emissions by at least 80 percent by 2050 compared with 1990 levels. Energy efficiency will play a “critical” role in achieving these objectives by contributing more than half of the emissions reductions.
The following is an overview of steps being taken in key countries and regions including the European Union, the United States, China and India to enhance energy efficiency.
European Union
The EU in 2008 adopted a climate change package aimed at reducing emissions by 20 percent by 2020 and at meeting 20 percent of its energy needs from renewable sources.
The EU pledged to deepen the cuts in emissions to 30 percent, provided other developed countries commit themselves to comparable reductions.
The United States
Through several programs, the U.S. is seeking to reduce its dependence on oil, and is promoting energy efficieny and the use of alternative resources.
Several states are taking action of their own. Ten north-eastern states are part of the Regional Greenhouse Gas Initiative that aims to reduce emissions from power stations by 10 percent by 2018. California in August 2006 approved legislation requiring a 25 percent reduction in state carbon dioxide emissions by 2020.
China
China is the largest emitter of carbon dioxide emissions, although its per-capita emissions are still well below those of developed nations. The country's latest five-year development plan lists energy and environmental challenges among issues of priority.
The plan for the years 2006 to 2010 calls for a 20 percent reduction in the amount of energy used per unit of gross domestic product (GDP). It also aims to reduce emissions of major pollutants by 10 percent.
India
India announced a National Action Plan on Climate Change in June 2008, which calls for savings of 10,000 MW by 2012 from energy efficiency measures and a “graduated shift” from fossil fuels to renewable sources of energy.
Other national policies
The International Energy Agency's (IEA) database of national policies on energy efficiency provides a comprehensive guide to the measures being taken by governments around the world.
Energy efficiency policies have been maturing over the years. A study commissioned by the IEA assesses the lessons to be learned from recent decades.
For additional links to government-related Web sites, please see the list in the right-hand column of this page.