111-508: The Benning Road Power Plant was a power plant owned by PEPCO and located in Washington, D.C. The 19-acre facility was built in 1906, and underwent several changes before being demolished in 2012. The facility was powered by coal until 1976, when it was converted to petroleum. By the early 2000s, the facility was capable of producing 550 megawatts of electricity and operated for an average of 10–15 days per year. The plant's location in
222-583: A consent decree with the government of Washington DC due to the company's years of releases of PCBs into the river. In 2017, PEPCO agreed to pay regulators $ 1.6 million for violations of the Clean Water Act . In 2014, the plant was stripped of hazardous materials and then demolished, leaving a 19-acre undeveloped riverfront site in a dense urban area. The facility was extremely close to the Minnesota Avenue station . There have been calls for
333-467: A greenhouse gas which is a major contributor to global warming . The results of a recent study show that the net income available to shareholders of large companies could see a significant reduction from the greenhouse gas emissions liability related to only natural disasters in the United States from a single coal-fired power plant. However, as of 2015, no such cases have awarded damages in
444-562: A broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is driven by human activities , especially fossil fuel burning since the Industrial Revolution . Fossil fuel use, deforestation , and some agricultural and industrial practices release greenhouse gases . These gases absorb some of the heat that the Earth radiates after it warms from sunlight , warming
555-630: A cooler cooling system. However, it may be used in cogeneration plants to heat buildings, produce hot water, or to heat materials on an industrial scale, such as in some oil refineries , plants, and chemical synthesis plants. Typical thermal efficiency for utility-scale electrical generators is around 37% for coal and oil-fired plants, and 56 – 60% (LEV) for combined-cycle gas-fired plants. Plants designed to achieve peak efficiency while operating at capacity will be less efficient when operating off-design (i.e. temperatures too low.) Practical fossil fuels stations operating as heat engines cannot exceed
666-404: A cooler medium must be equal or larger than the ratio of absolute temperatures of the cooling system (environment) and the heat source (combustion furnace). Raising the furnace temperature improves the efficiency but complicates the design, primarily by the selection of alloys used for construction, making the furnace more expensive. The waste heat cannot be converted into mechanical energy without
777-590: A decadal timescale. Other changes are caused by an imbalance of energy from external forcings . Examples of these include changes in the concentrations of greenhouse gases , solar luminosity , volcanic eruptions, and variations in the Earth's orbit around the Sun. To determine the human contribution to climate change, unique "fingerprints" for all potential causes are developed and compared with both observed patterns and known internal climate variability . For example, solar forcing—whose fingerprint involves warming
888-503: A factory or data center, or may also be operated in parallel with the local utility system to reduce peak power demand charge from the utility. Diesel engines can produce strong torque at relatively low rotational speeds, which is generally desirable when driving an alternator , but diesel fuel in long-term storage can be subject to problems resulting from water accumulation and chemical decomposition . Rarely used generator sets may correspondingly be installed as natural gas or LPG to minimize
999-491: A fine filter that collects the ash particles, electrostatic precipitators use an electric field to trap ash particles on high-voltage plates, and cyclone collectors use centrifugal force to trap particles to the walls. A recent study indicates that sulfur emissions from fossil fueled power stations in China may have caused a 10-year lull in global warming (1998-2008). Fossil-fuel power stations, particularly coal-fired plants, are
1110-478: A fossil fuel power plant the chemical energy stored in fossil fuels such as coal , fuel oil , natural gas or oil shale and oxygen of the air is converted successively into thermal energy , mechanical energy and, finally, electrical energy . Each fossil fuel power plant is a complex, custom-designed system. Multiple generating units may be built at a single site for more efficient use of land , natural resources and labor . Most thermal power stations in
1221-427: A largely African American and low-income portion of Northeast, Washington, D.C. raised environmental justice concerns for decades. The Plant produced air pollution that negatively affected neighboring communities. The facility also contributed to water pollution in the neighboring Anacostia River , releasing PCBs , lead, iron, cadmium, zinc, and other hazardous materials into the waterway. In 2011, PEPCO entered into
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#17327733099581332-542: A lot of light to being dark after the ice has melted, they start absorbing more heat . Local black carbon deposits on snow and ice also contribute to Arctic warming. Arctic surface temperatures are increasing between three and four times faster than in the rest of the world. Melting of ice sheets near the poles weakens both the Atlantic and the Antarctic limb of thermohaline circulation , which further changes
1443-636: A major source of industrial wastewater . Wastewater streams include flue-gas desulfurization, fly ash, bottom ash and flue gas mercury control. Plants with air pollution controls such as wet scrubbers typically transfer the captured pollutants to the wastewater stream. Ash ponds , a type of surface impoundment, are a widely used treatment technology at coal-fired plants. These ponds use gravity to settle out large particulates (measured as total suspended solids ) from power plant wastewater. This technology does not treat dissolved pollutants. Power stations use additional technologies to control pollutants, depending on
1554-412: A marked increase in temperature. Ongoing changes in climate have had no precedent for several thousand years. Multiple independent datasets all show worldwide increases in surface temperature, at a rate of around 0.2 °C per decade. The 2014–2023 decade warmed to an average 1.19 °C [1.06–1.30 °C] compared to the pre-industrial baseline (1850–1900). Not every single year was warmer than
1665-408: A particular fuel. As an example, a new 1500 MW supercritical lignite-fueled power station running on average at half its capacity might have annual CO 2 emissions estimated as: = 1500MW x 0.5 x 100/40 x 101000 kg/TJ x 1year = 1500MJ/s x 0.5 x 2.5 x 0.101 kg/MJ x 365x24x60x60s = 1.5x10 x 5x10 x 2.5 x 1.01 x 3.1536x10 kg = 59.7 x10 kg = 5.97 Mt Thus the example power station
1776-408: A physical climate model. These models simulate how population, economic growth , and energy use affect—and interact with—the physical climate. With this information, these models can produce scenarios of future greenhouse gas emissions. This is then used as input for physical climate models and carbon cycle models to predict how atmospheric concentrations of greenhouse gases might change. Depending on
1887-461: A result of climate change. Global sea level is rising as a consequence of thermal expansion and the melting of glaciers and ice sheets . Sea level rise has increased over time, reaching 4.8 cm per decade between 2014 and 2023. Over the 21st century, the IPCC projects 32–62 cm of sea level rise under a low emission scenario, 44–76 cm under an intermediate one and 65–101 cm under
1998-474: A result. The World Health Organization calls climate change one of the biggest threats to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming . Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for
2109-433: A serious impact on public health. Power plants remove particulate from the flue gas with the use of a bag house or electrostatic precipitator . Several newer plants that burn coal use a different process, Integrated Gasification Combined Cycle in which synthesis gas is made out of a reaction between coal and water. The synthesis gas is processed to remove most pollutants and then used initially to power gas turbines. Then
2220-417: A small share of global emissions , yet have the least ability to adapt and are most vulnerable to climate change . Many climate change impacts have been observed in the first decades of the 21st century, with 2023 the warmest on record at +1.48 °C (2.66 °F) since regular tracking began in 1850. Additional warming will increase these impacts and can trigger tipping points , such as melting all of
2331-548: A very high emission scenario. Marine ice sheet instability processes in Antarctica may add substantially to these values, including the possibility of a 2-meter sea level rise by 2100 under high emissions. Climate change has led to decades of shrinking and thinning of the Arctic sea ice . While ice-free summers are expected to be rare at 1.5 °C degrees of warming, they are set to occur once every three to ten years at
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#17327733099582442-519: A warming level of 2 °C. Higher atmospheric CO 2 concentrations cause more CO 2 to dissolve in the oceans, which is making them more acidic . Because oxygen is less soluble in warmer water, its concentrations in the ocean are decreasing , and dead zones are expanding. Greater degrees of global warming increase the risk of passing through ' tipping points '—thresholds beyond which certain major impacts can no longer be avoided even if temperatures return to their previous state. For instance,
2553-644: Is a deceiving baseline for comparison: just the Chernobyl nuclear disaster released, in iodine-131 alone, an estimated 1.76 EBq. of radioactivity, a value one order of magnitude above this value for total emissions from all coal burned within a century, while the iodine-131, the major radioactive substance which comes out in accident situations, has a half life of just 8 days. Global warming Present-day climate change includes both global warming —the ongoing increase in global average temperature —and its wider effects on Earth's climate . Climate change in
2664-424: Is a relatively cheap fuel. Coal is an impure fuel and produces more greenhouse gas and pollution than an equivalent amount of petroleum or natural gas. For instance, the operation of a 1000-MWe coal-fired power plant results in a nuclear radiation dose of 490 person-rem/year, compared to 136 person-rem/year for an equivalent nuclear power plant, including uranium mining, reactor operation and waste disposal. Coal
2775-564: Is an estimated total sea level rise of 2.3 metres per degree Celsius (4.2 ft/°F) after 2000 years. Oceanic CO 2 uptake is slow enough that ocean acidification will also continue for hundreds to thousands of years. Deep oceans (below 2,000 metres (6,600 ft)) are also already committed to losing over 10% of their dissolved oxygen by the warming which occurred to date. Further, the West Antarctic ice sheet appears committed to practically irreversible melting, which would increase
2886-419: Is burned that significant amounts of these substances are released. A 1,000 MW coal-burning power plant could have an uncontrolled release of as much as 5.2 metric tons per year of uranium (containing 74 pounds (34 kg) of uranium-235 ) and 12.8 metric tons per year of thorium. In comparison, a 1,000 MW nuclear plant will generate about 30 metric tons of high-level radioactive solid packed waste per year. It
2997-553: Is caused by the emission of nitrogen oxides and sulfur dioxide . These gases may be only mildly acidic themselves, yet when they react with the atmosphere, they create acidic compounds such as sulfurous acid , nitric acid and sulfuric acid which fall as rain, hence the term acid rain. In Europe and the US, stricter emission laws and decline in heavy industries have reduced the environmental hazards associated with this problem, leading to lower emissions after their peak in 1960s. In 2008,
3108-428: Is converted to steam in the boiler; additional heating stages may be included to superheat the steam. The hot steam is sent through controlling valves to a turbine. As the steam expands and cools, its energy is transferred to the turbine blades which turn a generator. The spent steam has very low pressure and energy content; this water vapor is fed through a condenser, which removes heat from the steam. The condensed water
3219-403: Is delivered by highway truck , rail , barge , collier ship or coal slurry pipeline . Generating stations adjacent to a mine may receive coal by conveyor belt or massive diesel-electric -drive trucks . Coal is usually prepared for use by crushing the rough coal to pieces less than 2 inches (5 cm) in size. Gas is a very common fuel and has mostly replaced coal in countries where gas
3330-711: Is determined by modelling the carbon cycle and climate sensitivity to greenhouse gases. According to UNEP , global warming can be kept below 1.5 °C with a 50% chance if emissions after 2023 do not exceed 200 gigatonnes of CO 2 . This corresponds to around 4 years of current emissions. To stay under 2.0 °C, the carbon budget is 900 gigatonnes of CO 2 , or 16 years of current emissions. The climate system experiences various cycles on its own which can last for years, decades or even centuries. For example, El Niño events cause short-term spikes in surface temperature while La Niña events cause short term cooling. Their relative frequency can affect global temperature trends on
3441-507: Is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the Three Mile Island incident . The collective radioactivity resulting from all coal burning worldwide between 1937 and 2040 is estimated to be 2,700,000 curies or 0.101 EBq. During normal operation, the effective dose equivalent from coal plants is 100 times that from nuclear plants. Normal operation however,
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3552-421: Is estimated to emit about 6 megatonnes of carbon dioxide each year. The results of similar estimations are mapped by organisations such as Global Energy Monitor , Carbon Tracker and ElectricityMap. Alternatively it may be possible to measure CO 2 emissions (perhaps indirectly via another gas) from satellite observations. Another problem related to coal combustion is the emission of particulates that have
3663-399: Is independent of where greenhouse gases are emitted, because the gases persist long enough to diffuse across the planet. Since the pre-industrial period, the average surface temperature over land regions has increased almost twice as fast as the global average surface temperature. This is because oceans lose more heat by evaporation and oceans can store a lot of heat . The thermal energy in
3774-450: Is primarily attributed to sulfate aerosols produced by the combustion of fossil fuels with heavy sulfur concentrations like coal and bunker fuel . Smaller contributions come from black carbon (from combustion of fossil fuels and biomass), and from dust. Globally, aerosols have been declining since 1990 due to pollution controls, meaning that they no longer mask greenhouse gas warming as much. Aerosols also have indirect effects on
3885-444: Is radiating into space. Warming reduces average snow cover and forces the retreat of glaciers . At the same time, warming also causes greater evaporation from the oceans , leading to more atmospheric humidity , more and heavier precipitation . Plants are flowering earlier in spring, and thousands of animal species have been permanently moving to cooler areas. Different regions of the world warm at different rates . The pattern
3996-660: Is referred to as a combined cycle power plant because it combines the Brayton cycle of the gas turbine with the Rankine cycle of the HRSG. The turbines are fueled either with natural gas or fuel oil. Diesel engine generator sets are often used for prime power in communities not connected to a widespread power grid. Emergency (standby) power systems may use reciprocating internal combustion engines operated by fuel oil or natural gas. Standby generators may serve as emergency power for
4107-516: Is shaped by feedbacks, which either amplify or dampen the change. Self-reinforcing or positive feedbacks increase the response, while balancing or negative feedbacks reduce it. The main reinforcing feedbacks are the water-vapour feedback , the ice–albedo feedback , and the net effect of clouds. The primary balancing mechanism is radiative cooling , as Earth's surface gives off more heat to space in response to rising temperature. In addition to temperature feedbacks, there are feedbacks in
4218-464: Is still important as the fuel source for diesel engine power plants used especially in isolated communities not interconnected to a grid. Liquid fuels may also be used by gas turbine power plants, especially for peaking or emergency service. Of the three fossil fuel sources, oil has the advantages of easier transportation and handling than solid coal, and easier on-site storage than natural gas. Combined heat and power (CHP), also known as cogeneration ,
4329-502: Is still unknown as to which kinds of particulate matter pose the most harm, which makes it difficult to come up with adequate legislation for regulating particulate matter. There are several methods of helping to reduce the particulate matter emissions from coal-fired plants. Roughly 80% of the ash falls into an ash hopper, but the rest of the ash then gets carried into the atmosphere to become coal-fly ash. Methods of reducing these emissions of particulate matter include: The baghouse has
4440-462: Is the " nameplate capacity " or the maximum allowed output of the plant, " capacity factor " or "load factor" is a measure of the amount of power that a plant produces compared with the amount it would produce if operated at its rated capacity nonstop, heat rate is thermal energy in/electrical energy out, emission intensity (also called emission factor ) is the CO 2 emitted per unit of heat generated for
4551-407: Is the major reason why different climate models project different magnitudes of warming for a given amount of emissions. A climate model is a representation of the physical, chemical and biological processes that affect the climate system. Models include natural processes like changes in the Earth's orbit, historical changes in the Sun's activity, and volcanic forcing. Models are used to estimate
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4662-536: Is the use of a thermal power station to provide both electric power and heat (the latter being used, for example, for district heating purposes). This technology is practiced not only for domestic heating (low temperature) but also for industrial process heat, which is often high temperature heat. Calculations show that Combined Heat and Power District Heating (CHPDH) is the cheapest method in reducing (but not eliminating) carbon emissions, if conventional fossil fuels remain to be burned. Thermal power plants are one of
4773-433: Is then pumped into the boiler to repeat the cycle. Emissions from the boiler include carbon dioxide, oxides of sulfur, and in the case of coal fly ash from non-combustible substances in the fuel. Waste heat from the condenser is transferred either to the air, or sometimes to a cooling pond, lake or river. One type of fossil fuel power plant uses a gas turbine in conjunction with a heat recovery steam generator (HRSG). It
4884-417: Is unclear. A related phenomenon driven by climate change is woody plant encroachment , affecting up to 500 million hectares globally. Climate change has contributed to the expansion of drier climate zones, such as the expansion of deserts in the subtropics . The size and speed of global warming is making abrupt changes in ecosystems more likely. Overall, it is expected that climate change will result in
4995-465: Is what remains after the coal has been combusted, so it consists of the incombustible materials that are found in the coal. The size and chemical composition of these particles affects the impacts on human health. Currently coarse (diameter greater than 2.5 μm) and fine (diameter between 0.1 μm and 2.5 μm) particles are regulated, but ultrafine particles (diameter less than 0.1 μm) are currently unregulated, yet they pose many dangers. Unfortunately much
5106-511: The Atlantic meridional overturning circulation (AMOC), and irreversible damage to key ecosystems like the Amazon rainforest and coral reefs can unfold in a matter of decades. The long-term effects of climate change on oceans include further ice melt, ocean warming , sea level rise, ocean acidification and ocean deoxygenation. The timescale of long-term impacts are centuries to millennia due to CO 2 's long atmospheric lifetime. The result
5217-522: The Carnot cycle limit for conversion of heat energy into useful work. Fuel cells do not have the same thermodynamic limits as they are not heat engines. The efficiency of a fossil fuel plant may be expressed as its heat rate , expressed in BTU/kilowatthour or megajoules/kilowatthour. In a steam turbine power plant, fuel is burned in a furnace and the hot gasses flow through a boiler. Water
5328-621: The Carnot efficiency and therefore produce waste heat . Fossil fuel power stations provide most of the electrical energy used in the world. Some fossil-fired power stations are designed for continuous operation as baseload power plants , while others are used as peaker plants . However, starting from the 2010s, in many countries plants designed for baseload supply are being operated as dispatchable generation to balance increasing generation by variable renewable energy . By-products of fossil fuel power plant operation must be considered in their design and operation. Flue gas from combustion of
5439-661: The Earth's energy budget . Sulfate aerosols act as cloud condensation nuclei and lead to clouds that have more and smaller cloud droplets. These clouds reflect solar radiation more efficiently than clouds with fewer and larger droplets. They also reduce the growth of raindrops , which makes clouds more reflective to incoming sunlight. Indirect effects of aerosols are the largest uncertainty in radiative forcing . While aerosols typically limit global warming by reflecting sunlight, black carbon in soot that falls on snow or ice can contribute to global warming. Not only does this increase
5550-828: The European Environment Agency (EEA) documented fuel-dependent emission factors based on actual emissions from power plants in the European Union . Electricity generation using carbon-based fuels is responsible for a large fraction of carbon dioxide (CO 2 ) emissions worldwide and for 34% of U.S. man-made carbon dioxide emissions in 2010. In the U.S. 70% of electricity is generated by combustion of fossil fuels. Coal contains more carbon than oil or natural gas fossil fuels, resulting in greater volumes of carbon dioxide emissions per unit of electricity generated. In 2010, coal contributed about 81% of CO 2 emissions from generation and contributed about 45% of
5661-573: The Greenland ice sheet is already melting, but if global warming reaches levels between 1.7 °C and 2.3 °C, its melting will continue until it fully disappears. If the warming is later reduced to 1.5 °C or less, it will still lose a lot more ice than if the warming was never allowed to reach the threshold in the first place. While the ice sheets would melt over millennia, other tipping points would occur faster and give societies less time to respond. The collapse of major ocean currents like
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#17327733099585772-840: The Greenland ice sheet . Under the 2015 Paris Agreement , nations collectively agreed to keep warming "well under 2 °C". However, with pledges made under the Agreement, global warming would still reach about 2.8 °C (5.0 °F) by the end of the century. Limiting warming to 1.5 °C would require halving emissions by 2030 and achieving net-zero emissions by 2050. Fossil fuel use can be phased out by conserving energy and switching to energy sources that do not produce significant carbon pollution. These energy sources include wind , solar , hydro , and nuclear power . Cleanly generated electricity can replace fossil fuels for powering transportation , heating buildings , and running industrial processes. Carbon can also be removed from
5883-635: The Industrial Revolution , naturally-occurring amounts of greenhouse gases caused the air near the surface to be about 33 °C warmer than it would have been in their absence. Human activity since the Industrial Revolution, mainly extracting and burning fossil fuels ( coal , oil , and natural gas ), has increased the amount of greenhouse gases in the atmosphere. In 2022, the concentrations of CO 2 and methane had increased by about 50% and 164%, respectively, since 1750. These CO 2 levels are higher than they have been at any time during
5994-518: The World Economic Forum , 14.5 million more deaths are expected due to climate change by 2050. 30% of the global population currently live in areas where extreme heat and humidity are already associated with excess deaths. By 2100, 50% to 75% of the global population would live in such areas. While total crop yields have been increasing in the past 50 years due to agricultural improvements, climate change has already decreased
6105-414: The carbon cycle . While plants on land and in the ocean absorb most excess emissions of CO 2 every year, that CO 2 is returned to the atmosphere when biological matter is digested, burns, or decays. Land-surface carbon sink processes, such as carbon fixation in the soil and photosynthesis, remove about 29% of annual global CO 2 emissions. The ocean has absorbed 20 to 30% of emitted CO 2 over
6216-402: The climate system . Solar irradiance has been measured directly by satellites , and indirect measurements are available from the early 1600s onwards. Since 1880, there has been no upward trend in the amount of the Sun's energy reaching the Earth, in contrast to the warming of the lower atmosphere (the troposphere ). The upper atmosphere (the stratosphere ) would also be warming if the Sun
6327-971: The extinction of many species. The oceans have heated more slowly than the land, but plants and animals in the ocean have migrated towards the colder poles faster than species on land. Just as on land, heat waves in the ocean occur more frequently due to climate change, harming a wide range of organisms such as corals, kelp , and seabirds . Ocean acidification makes it harder for marine calcifying organisms such as mussels , barnacles and corals to produce shells and skeletons ; and heatwaves have bleached coral reefs . Harmful algal blooms enhanced by climate change and eutrophication lower oxygen levels, disrupt food webs and cause great loss of marine life. Coastal ecosystems are under particular stress. Almost half of global wetlands have disappeared due to climate change and other human impacts. Plants have come under increased stress from damage by insects. The effects of climate change are impacting humans everywhere in
6438-460: The fossil fuels contains carbon dioxide and water vapor, as well as pollutants such as nitrogen oxides (NO x ), sulfur oxides (SO x ), and, for coal-fired plants, mercury , traces of other metals, and fly ash . Usually all of the carbon dioxide and some of the other pollution is discharged to the air. Solid waste ash from coal-fired boilers must also be removed. Fossil fueled power stations are major emitters of carbon dioxide (CO 2 ),
6549-436: The greenhouse gas carbon dioxide within the atmosphere will "very likely" lead to higher average temperatures on a global scale ( global warming ). Concerns regarding the potential for such warming to change the global climate prompted IPCC recommendations calling for large cuts to CO 2 emissions worldwide. Emissions can be reduced with higher combustion temperatures, yielding more efficient production of electricity within
6660-450: The heat energy of combustion into mechanical energy , which then operates an electrical generator . The prime mover may be a steam turbine , a gas turbine or, in small plants, a reciprocating gas engine . All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by
6771-432: The socioeconomic scenario and the mitigation scenario, models produce atmospheric CO 2 concentrations that range widely between 380 and 1400 ppm. The environmental effects of climate change are broad and far-reaching, affecting oceans , ice, and weather. Changes may occur gradually or rapidly. Evidence for these effects comes from studying climate change in the past, from modelling, and from modern observations. Since
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#17327733099586882-405: The 18th century and 1970 there was little net warming, as the warming impact of greenhouse gas emissions was offset by cooling from sulfur dioxide emissions. Sulfur dioxide causes acid rain , but it also produces sulfate aerosols in the atmosphere, which reflect sunlight and cause global dimming . After 1970, the increasing accumulation of greenhouse gases and controls on sulfur pollution led to
6993-612: The 1950s, droughts and heat waves have appeared simultaneously with increasing frequency. Extremely wet or dry events within the monsoon period have increased in India and East Asia. Monsoonal precipitation over the Northern Hemisphere has increased since 1980. The rainfall rate and intensity of hurricanes and typhoons is likely increasing , and the geographic range likely expanding poleward in response to climate warming. Frequency of tropical cyclones has not increased as
7104-500: The 1980s, the terms global warming and climate change became more common, often being used interchangeably. Scientifically, global warming refers only to increased surface warming, while climate change describes both global warming and its effects on Earth's climate system , such as precipitation changes. Climate change can also be used more broadly to include changes to the climate that have happened throughout Earth's history. Global warming —used as early as 1975 —became
7215-440: The Arctic is forcing many species to relocate or become extinct . Even if efforts to minimize future warming are successful, some effects will continue for centuries. These include ocean heating , ocean acidification and sea level rise . Climate change threatens people with increased flooding , extreme heat, increased food and water scarcity, more disease, and economic loss . Human migration and conflict can also be
7326-435: The Arctic is another major feedback, this reduces the reflectivity of the Earth's surface in the region and accelerates Arctic warming . This additional warming also contributes to permafrost thawing, which releases methane and CO 2 into the atmosphere. Around half of human-caused CO 2 emissions have been absorbed by land plants and by the oceans. This fraction is not static and if future CO 2 emissions decrease,
7437-497: The CO 2 released by the chemical reactions for making cement , steel , aluminum , and fertilizer . Methane emissions come from livestock , manure, rice cultivation , landfills, wastewater, and coal mining , as well as oil and gas extraction . Nitrous oxide emissions largely come from the microbial decomposition of fertilizer . While methane only lasts in the atmosphere for an average of 12 years, CO 2 lasts much longer. The Earth's surface absorbs CO 2 as part of
7548-604: The Earth will be able to absorb up to around 70%. If they increase substantially, it'll still absorb more carbon than now, but the overall fraction will decrease to below 40%. This is because climate change increases droughts and heat waves that eventually inhibit plant growth on land, and soils will release more carbon from dead plants when they are warmer . The rate at which oceans absorb atmospheric carbon will be lowered as they become more acidic and experience changes in thermohaline circulation and phytoplankton distribution. Uncertainty over feedbacks, particularly cloud cover,
7659-518: The United States. Per unit of electric energy, brown coal emits nearly twice as much CO 2 as natural gas, and black coal emits somewhat less than brown. As of 2019 , carbon capture and storage of emissions is not economically viable for fossil fuel power stations, and keeping global warming below 1.5 °C is still possible but only if no more fossil fuel power plants are built and some existing fossil fuel power plants are shut down early, together with other measures such as reforestation . In
7770-441: The absorption of sunlight, it also increases melting and sea-level rise. Limiting new black carbon deposits in the Arctic could reduce global warming by 0.2 °C by 2050. The effect of decreasing sulfur content of fuel oil for ships since 2020 is estimated to cause an additional 0.05 °C increase in global mean temperature by 2050. As the Sun is the Earth's primary energy source, changes in incoming sunlight directly affect
7881-411: The atmosphere , for instance by increasing forest cover and farming with methods that capture carbon in soil . Before the 1980s it was unclear whether the warming effect of increased greenhouse gases was stronger than the cooling effect of airborne particulates in air pollution . Scientists used the term inadvertent climate modification to refer to human impacts on the climate at this time. In
7992-452: The atmosphere. volcanic CO 2 emissions are more persistent, but they are equivalent to less than 1% of current human-caused CO 2 emissions. Volcanic activity still represents the single largest natural impact (forcing) on temperature in the industrial era. Yet, like the other natural forcings, it has had negligible impacts on global temperature trends since the Industrial Revolution. The climate system's response to an initial forcing
8103-454: The biggest threats to global health in the 21st century. Scientists have warned about the irreversible harms it poses. Extreme weather events affect public health, and food and water security . Temperature extremes lead to increased illness and death. Climate change increases the intensity and frequency of extreme weather events. It can affect transmission of infectious diseases , such as dengue fever and malaria . According to
8214-540: The carbon cycle, such as the fertilizing effect of CO 2 on plant growth. Feedbacks are expected to trend in a positive direction as greenhouse gas emissions continue, raising climate sensitivity. These feedback processes alter the pace of global warming. For instance, warmer air can hold more moisture in the form of water vapour , which is itself a potent greenhouse gas. Warmer air can also make clouds higher and thinner, and therefore more insulating, increasing climate warming. The reduction of snow cover and sea ice in
8325-551: The climate cycled through ice ages . One of the hotter periods was the Last Interglacial , around 125,000 years ago, where temperatures were between 0.5 °C and 1.5 °C warmer than before the start of global warming. This period saw sea levels 5 to 10 metres higher than today. The most recent glacial maximum 20,000 years ago was some 5–7 °C colder. This period has sea levels that were over 125 metres (410 ft) lower than today. Temperatures stabilized in
8436-684: The current interglacial period beginning 11,700 years ago . This period also saw the start of agriculture. Historical patterns of warming and cooling, like the Medieval Warm Period and the Little Ice Age , did not occur at the same time across different regions. Temperatures may have reached as high as those of the late 20th century in a limited set of regions. Climate information for that period comes from climate proxies , such as trees and ice cores . Around 1850 thermometer records began to provide global coverage. Between
8547-423: The cycle. As of 2019 the price of emitting CO 2 to the atmosphere is much lower than the cost of adding carbon capture and storage (CCS) to fossil fuel power stations, so owners have not done so. The CO 2 emissions from a fossil fuel power station can be estimated with the following formula: CO 2 emissions = capacity x capacity factor x heat rate x emission intensity x time where "capacity"
8658-403: The degree of warming future emissions will cause when accounting for the strength of climate feedbacks . Models also predict the circulation of the oceans, the annual cycle of the seasons, and the flows of carbon between the land surface and the atmosphere. The physical realism of models is tested by examining their ability to simulate current or past climates. Past models have underestimated
8769-427: The destroyed trees release CO 2 , and are not replaced by new trees, removing that carbon sink . Between 2001 and 2018, 27% of deforestation was from permanent clearing to enable agricultural expansion for crops and livestock. Another 24% has been lost to temporary clearing under the shifting cultivation agricultural systems. 26% was due to logging for wood and derived products, and wildfires have accounted for
8880-401: The distribution of heat and precipitation around the globe. The World Meteorological Organization estimates there is an 80% chance that global temperatures will exceed 1.5 °C warming for at least one year between 2024 and 2028. The chance of the 5-year average being above 1.5 °C is almost half. The IPCC expects the 20-year average global temperature to exceed +1.5 °C in
8991-444: The dominant direct influence on temperature from land use change. Thus, land use change to date is estimated to have a slight cooling effect. Air pollution, in the form of aerosols, affects the climate on a large scale. Aerosols scatter and absorb solar radiation. From 1961 to 1990, a gradual reduction in the amount of sunlight reaching the Earth's surface was observed. This phenomenon is popularly known as global dimming , and
9102-610: The early 2030s. The IPCC Sixth Assessment Report (2021) included projections that by 2100 global warming is very likely to reach 1.0–1.8 °C under a scenario with very low emissions of greenhouse gases , 2.1–3.5 °C under an intermediate emissions scenario , or 3.3–5.7 °C under a very high emissions scenario . The warming will continue past 2100 in the intermediate and high emission scenarios, with future projections of global surface temperatures by year 2300 being similar to millions of years ago. The remaining carbon budget for staying beneath certain temperature increases
9213-510: The electricity generated in the United States. In 2000, the carbon intensity (CO 2 emissions) of U.S. coal thermal combustion was 2249 lbs/MWh (1,029 kg/MWh) while the carbon intensity of U.S. oil thermal generation was 1672 lb/MWh (758 kg/MWh or 211 kg/ GJ ) and the carbon intensity of U.S. natural gas thermal production was 1135 lb/MWh (515 kg/MWh or 143 kg/GJ). The Intergovernmental Panel on Climate Change ( IPCC ) reports that increased quantities of
9324-430: The entire atmosphere—is ruled out because only the lower atmosphere has warmed. Atmospheric aerosols produce a smaller, cooling effect. Other drivers, such as changes in albedo , are less impactful. Greenhouse gases are transparent to sunlight , and thus allow it to pass through the atmosphere to heat the Earth's surface. The Earth radiates it as heat , and greenhouse gases absorb a portion of it. This absorption slows
9435-431: The first central stations used reciprocating steam engines to drive generators. As the size of the electrical load to be served grew, reciprocating units became too large and cumbersome to install economically. The steam turbine rapidly displaced all reciprocating engines in central station service. Coal is the most abundant fossil fuel on the planet, and widely used as the source of energy in thermal power stations and
9546-573: The fuel system maintenance requirements. Spark-ignition internal combustion engines operating on gasoline (petrol), propane , or LPG are commonly used as portable temporary power sources for construction work, emergency power, or recreational uses. Reciprocating external combustion engines such as the Stirling engine can be run on a variety of fossil fuels, as well as renewable fuels or industrial waste heat. Installations of Stirling engines for power production are relatively uncommon. Historically,
9657-604: The global climate system has grown with only brief pauses since at least 1970, and over 90% of this extra energy has been stored in the ocean . The rest has heated the atmosphere , melted ice, and warmed the continents. The Northern Hemisphere and the North Pole have warmed much faster than the South Pole and Southern Hemisphere . The Northern Hemisphere not only has much more land, but also more seasonal snow cover and sea ice . As these surfaces flip from reflecting
9768-460: The hot exhaust gases from the gas turbines are used to generate steam to power a steam turbine. The pollution levels of such plants are drastically lower than those of "classic" coal power plants. Particulate matter from coal-fired plants can be harmful and have negative health impacts. Studies have shown that exposure to particulate matter is related to an increase of respiratory and cardiac mortality. Particulate matter can irritate small airways in
9879-572: The last 14 million years. Concentrations of methane are far higher than they were over the last 800,000 years. Global human-caused greenhouse gas emissions in 2019 were equivalent to 59 billion tonnes of CO 2 . Of these emissions, 75% was CO 2 , 18% was methane , 4% was nitrous oxide, and 2% was fluorinated gases . CO 2 emissions primarily come from burning fossil fuels to provide energy for transport , manufacturing, heating , and electricity. Additional CO 2 emissions come from deforestation and industrial processes , which include
9990-436: The last two decades. CO 2 is only removed from the atmosphere for the long term when it is stored in the Earth's crust, which is a process that can take millions of years to complete. Around 30% of Earth's land area is largely unusable for humans ( glaciers , deserts , etc.), 26% is forests , 10% is shrubland and 34% is agricultural land . Deforestation is the main land use change contributor to global warming, as
10101-441: The last: internal climate variability processes can make any year 0.2 °C warmer or colder than the average. From 1998 to 2013, negative phases of two such processes, Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) caused a short slower period of warming called the " global warming hiatus ". After the "hiatus", the opposite occurred, with years like 2023 exhibiting temperatures well above even
10212-608: The lower atmosphere. Carbon dioxide , the primary greenhouse gas driving global warming, has grown by about 50% and is at levels not seen for millions of years. Climate change has an increasingly large impact on the environment . Deserts are expanding , while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost , retreat of glaciers and sea ice decline . Higher temperatures are also causing more intense storms , droughts, and other weather extremes . Rapid environmental change in mountains , coral reefs , and
10323-428: The lungs, which can lead to increased problems with asthma, chronic bronchitis, airway obstruction, and gas exchange. There are different types of particulate matter, depending on the chemical composition and size. The dominant form of particulate matter from coal-fired plants is coal fly ash , but secondary sulfate and nitrate also comprise a major portion of the particulate matter from coal-fired plants. Coal fly ash
10434-479: The main artificial sources of producing toxic gases and particulate matter . Fossil fuel power plants cause the emission of pollutants such as NO x , SO x , CO 2 , CO, PM, organic gases and polycyclic aromatic hydrocarbons. World organizations and international agencies, like the IEA, are concerned about the environmental impact of burning fossil fuels , and coal in particular. The combustion of coal contributes
10545-413: The more popular term after NASA climate scientist James Hansen used it in his 1988 testimony in the U.S. Senate . Since the 2000s, climate change has increased usage. Various scientists, politicians and media may use the terms climate crisis or climate emergency to talk about climate change, and may use the term global heating instead of global warming . Over the last few million years
10656-488: The most to acid rain and air pollution , and has been connected with global warming . Due to the chemical composition of coal there are difficulties in removing impurities from the solid fuel prior to its combustion. Modern day coal power plants pollute less than older designs due to new " scrubber " technologies that filter the exhaust air in smoke stacks. However, emission levels of various pollutants are still on average several times greater than natural gas power plants and
10767-550: The particular wastestream in the plant. These include dry ash handling, closed-loop ash recycling, chemical precipitation, biological treatment (such as an activated sludge process), membrane systems, and evaporation-crystallization systems. In 2015 EPA published a regulation pursuant to the Clean Water Act that requires US power plants to use one or more of these technologies. Technological advancements in ion exchange membranes and electrodialysis systems has enabled high efficiency treatment of flue-gas desulfurization wastewater to meet
10878-619: The rate at which heat escapes into space, trapping heat near the Earth's surface and warming it over time. While water vapour (≈50%) and clouds (≈25%) are the biggest contributors to the greenhouse effect, they primarily change as a function of temperature and are therefore mostly considered to be feedbacks that change climate sensitivity . On the other hand, concentrations of gases such as CO 2 (≈20%), tropospheric ozone , CFCs and nitrous oxide are added or removed independently from temperature, and are therefore considered to be external forcings that change global temperatures. Before
10989-522: The rate of Arctic shrinkage and underestimated the rate of precipitation increase. Sea level rise since 1990 was underestimated in older models, but more recent models agree well with observations. The 2017 United States-published National Climate Assessment notes that "climate models may still be underestimating or missing relevant feedback processes". Additionally, climate models may be unable to adequately predict short-term regional climatic shifts. A subset of climate models add societal factors to
11100-622: The rate of yield growth . Fisheries have been negatively affected in multiple regions. While agricultural productivity has been positively affected in some high latitude areas, mid- and low-latitude areas have been negatively affected. According to the World Economic Forum, an increase in drought in certain regions could cause 3.2 million deaths from malnutrition by 2050 and stunting in children. With 2 °C warming, global livestock headcounts could decline by 7–10% by 2050, as less animal feed will be available. If
11211-405: The recent average. This is why the temperature change is defined in terms of a 20-year average, which reduces the noise of hot and cold years and decadal climate patterns, and detects the long-term signal. A wide range of other observations reinforce the evidence of warming. The upper atmosphere is cooling, because greenhouse gases are trapping heat near the Earth's surface, and so less heat
11322-411: The release of chemical compounds that influence clouds, and by changing wind patterns. In tropic and temperate areas the net effect is to produce significant warming, and forest restoration can make local temperatures cooler. At latitudes closer to the poles, there is a cooling effect as forest is replaced by snow-covered (and more reflective) plains. Globally, these increases in surface albedo have been
11433-476: The remaining 23%. Some forests have not been fully cleared, but were already degraded by these impacts. Restoring these forests also recovers their potential as a carbon sink. Local vegetation cover impacts how much of the sunlight gets reflected back into space ( albedo ), and how much heat is lost by evaporation . For instance, the change from a dark forest to grassland makes the surface lighter, causing it to reflect more sunlight. Deforestation can also modify
11544-530: The scrubbers transfer the captured pollutants to wastewater, which still requires treatment in order to avoid pollution of receiving water bodies. In these modern designs, pollution from coal-fired power plants comes from the emission of gases such as carbon dioxide, nitrogen oxides , and sulfur dioxide into the air, as well a significant volume of wastewater which may contain lead , mercury , cadmium and chromium , as well as arsenic , selenium and nitrogen compounds ( nitrates and nitrites ). Acid rain
11655-583: The sea levels by at least 3.3 m (10 ft 10 in) over approximately 2000 years. Recent warming has driven many terrestrial and freshwater species poleward and towards higher altitudes . For instance, the range of hundreds of North American birds has shifted northward at an average rate of 1.5 km/year over the past 55 years. Higher atmospheric CO 2 levels and an extended growing season have resulted in global greening. However, heatwaves and drought have reduced ecosystem productivity in some regions. The future balance of these opposing effects
11766-410: The site to be converted into a use that is beneficial to the community. Fossil fuel power station 2021 world electricity generation by source. Total generation was 28 petawatt-hours . A fossil fuel power station is a thermal power station which burns a fossil fuel , such as coal , oil , or natural gas , to produce electricity . Fossil fuel power stations have machinery to convert
11877-531: The updated EPA discharge limits. Coal is a sedimentary rock formed primarily from accumulated plant matter, and it includes many inorganic minerals and elements which were deposited along with organic material during its formation. As the rest of the Earth's crust , coal also contains low levels of uranium , thorium , and other naturally occurring radioactive isotopes whose release into the environment leads to radioactive contamination . While these substances are present as very small trace impurities, enough coal
11988-438: The world use fossil fuel, outnumbering nuclear , geothermal , biomass , or concentrated solar power plants. The second law of thermodynamics states that any closed-loop cycle can only convert a fraction of the heat produced during combustion into mechanical work . The rest of the heat, called waste heat , must be released into a cooler environment during the return portion of the cycle. The fraction of heat released into
12099-438: The world. Impacts can be observed on all continents and ocean regions, with low-latitude, less developed areas facing the greatest risk. Continued warming has potentially "severe, pervasive and irreversible impacts" for people and ecosystems. The risks are unevenly distributed, but are generally greater for disadvantaged people in developing and developed countries. The World Health Organization calls climate change one of
12210-455: Was found in the late 20th century or early 21st century, such as the US and UK. Sometimes coal-fired steam plants are refitted to use natural gas to reduce net carbon dioxide emissions. Oil-fuelled plants may be converted to natural gas to lower operating cost. Heavy fuel oil was once a significant source of energy for electric power generation. After oil price increases of the 1970s, oil was displaced by coal and later natural gas. Distillate oil
12321-524: Was sending more energy to Earth, but instead, it has been cooling. This is consistent with greenhouse gases preventing heat from leaving the Earth's atmosphere. Explosive volcanic eruptions can release gases, dust and ash that partially block sunlight and reduce temperatures, or they can send water vapour into the atmosphere, which adds to greenhouse gases and increases temperatures. These impacts on temperature only last for several years, because both water vapour and volcanic material have low persistence in
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