Energy Consumption Grows

The development of modern civilisation depends on reliable energy supplies. Economic growth, technological development and rising living standards require energy, although improvements in efficiency can reduce the amount of energy needed to provide the same services.

Energy Consumption Estimates by Sector in the United States, 1949—2025 (trillion Btu). A British thermal unit (Btu) is the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

During the last century, rapid economic and technological development was accompanied by a major increase in global energy use. Fossil fuels still supply most of the world’s energy, although low-emission sources are expanding rapidly. Oil, natural gas and coal are finite resources, but the size of economically recoverable reserves changes over time with technology, prices and new discoveries.

U.S. Primary Energy Consumption by Source, 1949—2025 (quadrillion Btu).

Global energy demand continues to grow, but the rate varies considerably from year to year. In 2025, global energy demand increased by about 1.3%, following growth of about 2% in 2024. Most of the increase is now concentrated in emerging and developing economies, while energy demand in many advanced economies grows more slowly or may decline in some years.

Growth in energy demand is distributed very unevenly across the world. Emerging and developing economies account for most of the increase, while demand in advanced economies generally grows more slowly. In 2024, emerging and developing economies accounted for more than 80% of the increase in global energy demand.

Future energy demand will need to be met while maintaining security of supply and limiting environmental impacts. Long-term energy systems must therefore combine sufficient capacity with efficiency, sustainability and low-emission technologies.

Resource Consumption Grows

Fossil fuels still provide a large share of global energy, but the energy mix is changing rapidly. Renewable energy and other low-emission technologies are expanding, particularly in electricity generation. In 2025, solar PV alone supplied more than one quarter of the increase in global primary energy demand, while low-emission sources together accounted for nearly 60% of total demand growth.

Fossil fuels remain major components of the global energy system, but they are finite resources. Their future consumption will depend not only on resource availability but also on technology, prices, energy policy, efficiency improvements and the expansion of low-emission alternatives.

Fossil fuels still play a major role in the global energy system, but renewable energy capacity is expanding at record rates. Solar and wind power are currently among the fastest-growing energy technologies, although replacing fossil fuels across electricity, heat, transport and industry remains a long-term process.

Natural gas produces less carbon dioxide during combustion than coal for the same amount of energy, but its overall climate impact also depends on methane emissions during production and transport. Global gas demand continues to grow, although future trends will depend on electrification, efficiency, energy policy and the expansion of low-emission alternatives.

Growth in oil demand has slowed in recent years as vehicle efficiency improves and electric vehicles become more widespread. Oil nevertheless remains important in aviation, shipping, petrochemicals and many parts of the transport sector.

Coal remains an important global energy source, particularly for electricity generation and heavy industry. Global coal demand increased only slightly in 2025, by about 0.4%, while its future role is increasingly affected by climate policies, air-quality requirements and competition from lower-emission technologies.

The role of renewable energy continues to expand rapidly. Its future growth will depend on technology costs, electricity grids, energy storage, permitting, investment conditions and national energy policies. As deployment increases and technologies mature, renewable energy is becoming increasingly competitive in many applications.

Population Increases

The world’s population grew from about 1.6 billion in 1900 to around 8.2 billion in 2024. However, the rate of population growth is slowing. According to the United Nations, the global population is projected to reach about 8.9 billion by 2035, around 9.7 billion by 2050 and peak at about 10.3 billion in the mid-2080s.

World population, 1—2,100 (millions). Historical estimates to 2024 and United Nations projections thereafter.

Population growth alone does not determine future energy demand. Per-capita energy use differs greatly between countries, and improvements in efficiency can reduce the energy required to provide housing, transport, industry and other services. Rising living standards and expanding access to modern energy services are also important factors.

Estimated regional populations, 1950—2020 (millions).

Energy access remains highly uneven. In 2023, more than 660 million people worldwide still lacked access to electricity, with the largest deficits concentrated in sub-Saharan Africa. Around 2.1 billion people still cook using open fires or inefficient stoves fuelled by biomass, coal, kerosene or other polluting fuels. Expanding access to clean and reliable energy will therefore increase energy demand particularly in developing regions, where much of the future population growth is also expected to occur.