Energy in Brief

Shale in the United States

December 15, 2016

Over the past decade, the combination of horizontal drilling and hydraulic fracturing has provided access to large volumes of oil and natural gas that were previously uneconomic to produce from low permeability geological formations composed of shale, sandstone, and carbonate (e.g., limestone).

How much U.S. electricity is generated from renewable energy?

May 5, 2016

U.S. power plants used renewable energy sources, including water, wind, biomass wood and waste, geothermal, and solar, to generate about 13% of the electricity produced in the United States during 2015.

How much of U.S. electricity supply comes from wind, and how does that compare with other countries?

March 4, 2016

The United States is the world's top producer of electricity generated by wind, a title it has held since 2008. U.S. wind power totaled nearly 182 million megawatthours (MWh) during 2014, equal to 4.4% of U.S. electricity generation and more than three times the wind power generated in the United States in 2008. The top five global producers of electricity from wind also include China, Germany, Spain, and India. Although the United States generates more electricity from wind than any another country, China has the largest amount of installed wind generating capacity.

How is the fuel mix for U.S. electricity generation changing?

February 19, 2016

In recent years, there have been changes in the mix of fuels used to generate electricity in the United States. Natural gas and renewable energy sources are accounting for an increasing share of U.S. electricity production, while coal-fired generation has generally declined. In its Annual Energy Outlook, the U.S. Energy Information Administration (EIA) projects the share of electricity generated from natural gas and nonhydro renewable energy sources, such as wind and solar, will grow through 2040, while the share of other fuels, such as coal and petroleum, will decline.

Who are the major players supplying the world oil market?

February 11, 2016

The world oil market is complex. Governments and private companies play various roles in moving oil from producers to consumers. Government-owned national oil companies (NOCs) control most of the world's proved oil reserves (75% in 2014) and oil production (58% in 2014). International oil companies (IOCs), which are often stockholder-owned corporations, make up the balance of global oil reserves and production. Proved oil reserves consist of the amount of oil in a given area, known with reasonable certainty, that current technology can recover cost effectively. Worldwide proved oil reserves in 2014 were almost 1.7 trillion barrels, and global oil production averaged roughly 93.2 million barrels a day.

What are greenhouse gases and how much are emitted by the United States?

January 20, 2016

Greenhouse gases trap heat from the sun and warm the planet's surface. Most U.S. greenhouse gas emissions are related to energy production and consumption. Most of those emissions are carbon dioxide (CO2) from the burning of fossil fuels. From 1990 to 2014, energy-related carbon dioxide emissions in the United States increased on average by about 0.3% per year.

What is the role of coal in the United States?

January 19, 2016

The United States has the world's largest estimated recoverable reserves of coal, and it is a net exporter of coal. In 2014, U.S. coal mines produced about 1 billion short tons of coal, the first increase in annual coal output in three years. More than 90% of the coal produced in the United States was used by U.S. power plants to generate electricity. Although coal has been the largest source of electricity generation in the United States for more than 60 years, its annual share of total net generation declined from nearly 50% in 2007 to 39% in 2014.

What are the major sources and users of energy in the United States?

December 29, 2015

The major energy sources consumed in the United States are petroleum (oil), natural gas, coal, nuclear energy, and renewable energy. The major user sectors of these energy sources are residential and commercial buildings, industry, transportation, and electric power. The pattern of energy use varies widely by sector. For example, petroleum provides 92% of the energy used for transportation, but only provides about 1% of the energy used to generate electric power. Understanding the relationships between the different energy sources and their uses provides insights into many important energy issues.

What is the electric power grid, and what are some challenges it faces?

December 22, 2015

The U.S. power grid is the electrical system that connects electricity producers and consumers by transmission and distribution lines and related facilities. The U.S. power grid has evolved into three large interconnected systems that move electricity around the country. Mandatory reliability standards have been developed by the electric power industry and have been approved by the Federal Energy Regulatory Commission (FERC) to ensure coordinated electric system operations. FERC is an independent federal agency that regulates the interstate transmission of natural gas, oil, and electricity.

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