Energy Efficiency

The global exchange for energy efficiency policies, data and analysis

Energy efficiency is the first fuel of a sustainable global energy system. It can mitigate climate change, improve energy security and grow economies while delivering environmental and social benefits. The IEA works with policy makers and stakeholders across the globe to scale up action on energy efficiency.

Energy efficiency is being outpaced by growth in energy demand, but a more efficient world is possible

In 2018, primary energy intensity - an important indicator of how much energy is used by the global economy - improved by just 1.2%, the slowest rate since 2010.

This was significantly slower than the 1.7% improvement in 2017 and marked the third year in a row the rate has declined. It was also well below the average 3% improvement consistent with the IEA's Efficient World Strategy, first described in Energy Efficiency 2018.

Improvements in primary energy intensity

	Intensity improvement rate 	Intensity improvement rate	
2000-09	1.3763079
2010-14	2.0635666
2015	2.9325519
2016	2.526278
2017	1.7152493
2018		1.2112331
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However, by taking a range of cost-effective energy efficiency opportunities widely available today, energy intensity would improve by around 3% per year, between now and 2040.

Explore the latest findings in Energy Efficiency 2019 report

Energy Efficiency 2019

Released: 4 November 2019

Since 2015, improvements in global energy intensity have been weakening each year. Energy Efficiency 2019 examines the reasons for this slowdown, which has major implications for consumers, businesses, governments and the environment. The rate at which energy-using technologies are becoming more efficient is slackening, and at the same time societal changes are adding to energy demand faster than technological change can keep up. On top of this, progress on policy and investment remains flat.

Energy Efficiency 2019 is the authoritative tracker of global energy efficiency trends, providing policy makers and others in the energy sector with crucial insights into the status of global energy efficiency.

Explore the findings Download the full report

The IEA's work on energy efficiency

The IEA is the global authority for energy efficiency data, analysis and policy advice. Our Energy Efficiency Market Report is the annual tracker of energy efficiency progress globally. The IEA also facilitates the exchange of knowledge through our training programs, workshops, and research collaborations, and works to support energy efficiency globally with partners and at key global fora such as the G7 and G20.

The IEA helps governments unlock the vast potential of energy efficiency, advising them on developing, implementing and measuring the impacts of policies. Through the policies and measures database, the IEA tracks global policy progress in over 200 countries, regions and states. The IEA also tracks global investment in energy efficiency as published in the World Energy Investment report, as well as through our global survey of Energy Service Company (ESCO) markets.

Energy efficiency in emerging economies

Since 2014, through the Energy Efficiency in Emerging Economies Programme (E4 Programme) the IEA has been working closely with the governments of Brazil, China, India, Indonesia, Mexico, and South Africa as well as with regional and multilateral platforms including the Association of Southeast Asian Nations (ASEAN) and G20. Collectively the six E4 countries represent more than a third of the world's current energy use, which is projected to rise to more than 40% of global consumption by 2040.

Explore efficiency by sector

Information, data and resources and learn about efficiency opportunities in each sector.

Economy-wide Buildings Transport Industry


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Modernising energy efficiency through digitalisation

With digital technologies bringing significant change to the energy system, the IEA is examining the implications of digitalisation for energy efficiency. Learn more about our work on this topic and explore the 200+ resources in our digitalisation resource library.

Explore the IEA's work on this topic

Latest publications

Benefits of energy efficiency

The term multiple benefits aims to capture a reality that is often overlooked: investment in energy efficiency can provide many different benefits to many different stakeholders.

Use the selector below to learn about the multiple benefits of energy efficiency and find related resources.


Energy access

Energy efficiency on both the supply and demand sides has a role to play in increasing the available bandwidth in existing generation, transmission and distribution networks. Therefore energy efficiency is vital to improving energy access globally.

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Health and well-being

Energy efficiency measures can support good physical and mental health primarily by creating healthy indoor living environments with healthy air temperatures, humidity levels, noise levels, and improved air quality.

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Air Quality

Energy efficiency can reduce both indoor and outdoor concentrations of air pollutants, improving air quality.

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Emissions savings

Energy efficiency delivers a number of environmental benefits. It notably reduces GHG emissions, both direct emissions from fossil fuel combustion or consumption, and indirect emissions reductions from electricity generation.

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Household savings

Energy efficiency can improve disposable income by reducing the amount that households spend on energy for their homes and cars.

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Asset values

Energy efficiency can increase asset values for homeowners, businesses and utilities. Building owners can see increased property value from energy efficiency measures that lower energy consumption and reduce operating costs.

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In addition to reducing energy use and delivering cost savings, energy efficiency measures create numerous benefits for operators of industrial facilities. These include productivity gains, enhanced competiveness, improvements in product quality and working environments.

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Public budgets

Energy efficiency measures can deliver financial benefits to public budgets through both increased income and decreased expenses.

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Economic benefits

Cost-effective energy efficiency improvements can have positive macroeconomic impacts, boosting economic activity and often leading to increased employment. Energy efficiency reduces the amount of energy needed to deliver services, such as mobility, lighting, heating and cooling. Lowering the cost of energy services frees up resources for households, businesses and governments.

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Energy savings

Energy savings are at the heart of the multiple benefits of energy efficiency and link to many other economic, social and environmental benefits.

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Energy security

Energy efficiency can bolster regional or national energy security by avoiding additional energy imports and associated infrastructure.

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Energy prices

Energy efficiency can enable lower energy prices by reducing the need to add expensive new power generation or transmission capacity and by reducing pressure on energy resources.

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In other literature, the multiple benefits of energy efficiency have been variously labelled "co-benefits", "ancillary benefits" and "non-energy benefits" – terms often used interchangeably with “multiple benefits”. The IEA uses the term multiple benefits, which is broad enough to reflect the heterogeneous nature of outcomes of energy efficiency improvements and to avoid pre-emptive prioritisation of various benefits; different benefits will be of interest to different stakeholders.