Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is a type of fossil fuel, formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times.
Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production. In the United Kingdom and South Africa, a coal mine and its structures are a colliery, a coal mine is called a "pit", and above-ground mining structures are referred to as a "pit head". In Australia, "colliery" generally refers to an underground coal mine.
A non-renewable resource is a natural resource that cannot be readily replaced by natural means at a pace quick enough to keep up with consumption. An example is carbon-based fossil fuels. The original organic matter, with the aid of heat and pressure, becomes a fuel such as oil or gas. Earth minerals and metal ores, fossil fuels and groundwater in certain aquifers are all considered non-renewable resources, though individual elements are always conserved.
The Hubbert peak theory says that for any given geographical area, from an individual oil-producing region to the planet as a whole, the rate of petroleum production tends to follow a bell-shaped curve. It is one of the primary theories on peak oil.
Peak oil is the theorized point in time when the maximum rate of global oil production will occur, after which oil production will begin an irreversible decline. The primary concern of peak oil is that global transportation heavily relies upon the use of gasoline and diesel fuel. Switching transportation to electric vehicles, biofuels, or more fuel-efficient forms of travel may help reduce oil demand.
Oil depletion is the decline in oil production of a well, oil field, or geographic area. The Hubbert peak theory makes predictions of production rates based on prior discovery rates and anticipated production rates. Hubbert curves predict that the production curves of non-renewing resources approximate a bell curve. Thus, according to this theory, when the peak of production is passed, production rates enter an irreversible decline.
The Coal Question; An Inquiry Concerning the Progress of the Nation, and the Probable Exhaustion of Our Coal Mines is a book that economist William Stanley Jevons wrote in 1865 to explore the implications of Britain's reliance on coal. Given that coal was a finite, non-renewable energy resource, Jevons raised the question of sustainability. "Are we wise," he asked rhetorically, "in allowing the commerce of this country to rise beyond the point at which we can long maintain it?" His central thesis was that the supremacy of the United Kingdom of Great Britain and Ireland over global affairs was transitory, given the finite nature of its primary energy resource. In propounding this thesis, Jevons covered a range of issues central to sustainability, including limits to growth, overpopulation, overshoot, energy return on energy input (EROEI), taxation of energy resources, renewable energy alternatives, and resource peaking—a subject widely discussed today under the rubric of peak oil.
Energy in the United States is obtained from a diverse portfolio of sources, although the majority came from fossil fuels in 2021, as 36% of the nation's energy originated from petroleum, 32% from natural gas, and 11% from coal. Electricity from nuclear power supplied 8% and renewable energy supplied 12%, which includes biomass, wind, hydro, solar and geothermal.
China is both the world's largest energy consumer and the largest industrial country, and ensuring adequate energy supply to sustain economic growth has been a core concern of the Chinese Government since the founding of the People's Republic of China in 1949. Since the country's industrialization in the 1960s, China is currently the world's largest emitter of greenhouse gases, and coal in China is a major cause of global warming. However, from 2010 to 2015 China reduced energy consumption per unit of GDP by 18%, and CO2 emissions per unit of GDP by 20%. On a per-capita basis, China was only the world's 51st largest emitter of greenhouse gases in 2016. China is also the world's largest renewable energy producer, and the largest producer of hydroelectricity, solar power and wind power in the world. The energy policy of China is connected to its industrial policy, where the goals of China's industrial production dictate its energy demand managements.
Peak gas is the point in time when the maximum global natural gas production rate will be reached, after which the rate of production will enter its terminal decline. Although demand is peaking in the United States and Europe, it continues to rise globally due to consumers in Asia, especially China. Natural gas is a fossil fuel formed from plant matter over the course of millions of years. Natural gas derived from fossil fuels is a non-renewable energy source; however, methane can be renewable in other forms such as biogas. Peak coal was in 2013, and peak oil is forecast to occur before peak gas. One forecast is for natural gas demand to peak in 2035.
Fossil fuel phase-out is the gradual reduction of the use and production of fossil fuels to zero, to reduce deaths and illness from air pollution, limit climate change, and strengthen energy independence. It is part of the ongoing renewable energy transition, but is being hindered by fossil fuel subsidies.
Since 2013, total primary energy consumption in India has been the third highest in the world after China and United States. India is the second-top coal consumer in the year 2017 after China. India ranks third in oil consumption with 22.1 crore tons in 2017 after United States and China. India is net energy importer to meet nearly 47% of its total primary energy in 2019.
China is the largest producer and consumer of coal and coal power in the world. The share of coal in the Chinese energy mix declined to 55% in 2021 according to the US Energy Information Agency.
Peak oil is the point at which oil production, sometimes including unconventional oil sources, hits its maximum. Predicting the timing of peak oil involves estimation of future production from existing oil fields as well as future discoveries. The most influential production model is Hubbert peak theory, first proposed in the 1950s. The effect of peak oil on the world economy remains controversial.
Coal mining is an industry in transition in the United States. Production in 2019 was down 40% from the peak production of 1,171.8 million short tons in 2008. Employment of 43,000 coal miners is down from a peak of 883,000 in 1923. Generation of electricity is the largest user of coal, being used to produce 50% of electric power in 2005 and 27% in 2018. The U.S. is a net exporter of coal. U.S. coal exports, for which Europe is the largest customer, peaked in 2012. In 2015, the U.S. exported 7.0 percent of mined coal.
Sustainability measurement is a set of frameworks or indicators to measure how sustainable something is. This includes processes, products, services and businesses. Sustainability is difficult to quantify. It may even be impossible to measure. To measure sustainability, the indicators consider environmental, social and economic domains. The metrics are still evolving. They include indicators, benchmarks and audits. They include sustainability standards and certification systems like Fairtrade and Organic. They also involve indices and accounting. And they can include assessment, appraisal and other reporting systems. These metrics are used over a wide range of spatial and temporal scales. Sustainability measures include corporate sustainability reporting, Triple Bottom Line accounting. They include estimates of the quality of sustainability governance for individual countries. These use the Environmental Sustainability Index and Environmental Performance Index. Some methods let us track sustainable development. These include the UN Human Development Index and ecological footprints.
Energy security of the People's Republic of China concerns the need for the People's Republic of China to guarantee itself and its industries long- term access to sufficient energy and raw materials. China has been endeavoring to sign international agreements and secure such supplies; its energy security involves the internal and foreign energy policy of China. Currently, China's energy portfolio consists mainly of domestic coal, oil and gas from domestic and foreign sources, and small quantities of uranium. China has also created a strategic petroleum reserve, to secure emergency supplies of oil for temporary price and supply disruptions. Chinese policy focuses on diversification to reduce oil imports, which used to rely almost exclusively on producers in the Middle East.
Energy in Australia is the production in Australia of energy and electricity, for consumption or export. Energy policy of Australia describes the politics of Australia as it relates to energy.
Peak minerals marks the point in time when the largest production of a mineral will occur in an area, with production declining in subsequent years. While most mineral resources will not be exhausted in the near future, global extraction and production has become more challenging. Miners have found ways over time to extract deeper and lower grade ores with lower production costs. More than anything else, declining average ore grades are indicative of ongoing technological shifts that have enabled inclusion of more 'complex' processing – in social and environmental terms as well as economic – and structural changes in the minerals exploration industry and these have been accompanied by significant increases in identified Mineral Reserves.
Natural gas was the United States' largest source of energy production in 2016, representing 33 percent of all energy produced in the country. Natural gas has been the largest source of electrical generation in the United States since July 2015.
