In order to increase my understanding of energy and its relationship to sustainability for our project, I created a powerpoint outlining how different forms of energy are generated in the United States, in South Carolina, and in Greenville County.
Biomass energy was the first topic I researched. Biomass is organic material that comes from plants and animals, and it is a renewable source of energy, and it contains stored energy from the sun. Plants absorb the sun’s energy during photosynthesis, and when biomass is burned, the chemical energy in biomass is released as heat. Biomass can be burned directly or converted to liquid biofuels or biogas that can be burned as fuels. (EIA) Solid biomass, such as wood and garbage, can be burned directly to produce heat. Biomass can also be converted into a gas called biogas or into liquid biofuels such as ethanol and biodiesel. These fuels can then be burned for energy. (Ibid.)
Source: industryandbusiness.ca
Sources of biomass energy include using wood, wood pellets, and charcoal for heating and cooking can replace fossil fuels and may result in lower CO2 emissions overall. Wood can be harvested from forests, wood lots that have to be thinned, or from urban trees that fall down or have to be cut down. Using wood, however, has its drawbacks. Wood smoke contains harmful pollutants like carbon monoxide and particulate matter. Modern wood-burning stoves, pellet stoves, and fireplace inserts can reduce the amount of particulates from burning wood. Wood and charcoal are major cooking and heating fuels in poor countries, but if people harvest the wood faster than trees can grow, it causes deforestation. Planting fast-growing trees for fuel and using fuel-efficient cooking stoves can help slow deforestation and improve the environment. (EIA)
Burning municipal solid waste (MSW, or garbage) is another method of producing biomass energy, and it means that less waste is buried in landfills. On the other hand, burning garbage produces air pollution and releases the chemicals and substances in the waste into the air. Some of these chemicals can be hazardous to people and the environment if they are not properly controlled. The U.S. Environmental Protection Agency (EPA) applies strict environmental rules to waste-to-energy plants, and requires that waste-to-energy plants use air pollution control devices such as scrubbers, fabric filters, and electrostatic precipitators to capture air pollutants. (ibid.)
Disposing ash from MWS plants is also not without its associated issues. Ash can contain high concentrations of various metals that were present in the original waste. Textile dyes, printing inks, and ceramics, for example, may contain lead and cadmium. Separating waste before burning can solve part of the problem. Because batteries are the largest source of lead and cadmium in municipal waste, they should not be included in regular trash. Fluorescent light bulbs should also not be put in regular trash because they contain small amounts of mercury. The EPA tests ash from waste-to-energy plants to make sure that it is not hazardous. The test looks for chemicals and metals that could contaminate groundwater. Some MSW landfills use ash that is considered safe as a cover layer for their landfills, and some MSW ash is used to make concrete blocks and bricks. (Ibid.)
Collecting Landfill Gas or Biogas is another way that biomass fuel can be captured. Biogas forms as a result of biological processes in sewage treatment plants, waste landfills, and livestock manure management systems. Biogas is composed mainly of methane (a greenhouse gas) and CO2. Many facilities that produce biogas capture it and burn the methane for heat or to generate electricity. This electricity is considered renewable, and in many states, contributes to meeting state renewable portfolio standards (RPS). This electricity may replace electricity generation from fossil fuels and can result in a net reduction in CO2 emissions. Burning methane produces CO2, but because methane is a stronger greenhouse gas than CO2, the overall greenhouse effect is lower. (EIA)
Liquid Biofuels (Ethanol and Biodiesel) are byproducts of biomass that can serve as an energy source. Biofuels are transportation fuels such as ethanol and biodiesel. The federal government promotes ethanol use as a transportation fuel to help reduce oil imports and CO2 emissions. In 2007, the government set a target to use 36 billion gallons of biofuels by 2022. As a result, nearly all gasoline now sold in the United States contains some ethanol. Biofuels may be carbon-neutral because the plants that are used to make biofuels (such as corn and sugarcane for ethanol and soy beans and palm oil trees for biodiesel) absorb CO2 as they grow and may offset the CO2 emissions when biofuels are produced and burned. (Ibid.)
Biomass energy production occurs in the Upstate. Twin Chimneys landfill, which is located in Greenville County, has installed methane pipes in order to vent the gas that builds up in the decomposing waste. At the Enoree Landfill, which closed in early 2007, these pipes are being connected together so that the methane gas can be captured and sold for power generation. (Greenville County) Biomass production and consumption in South Carolina is approximately 121 trillion Btu per year. (EIA) As for the United States, biomass fuels provided about 5% of total primary energy use in 2017. Of that 5%, about 47% was from biofuels (mainly ethanol), 44% was from wood and wood-derived biomass, and 10% was from the biomass in municipal waste. (Sum of percentages is greater than 100% because of independent rounding) Researchers are trying to develop ways to use more biomass for fuel. (EIA)
https://www.greenvillecounty.org/solidwaste/Landfill.aspx
Nuclear energy is another form of energy that employs the use of nuclear fission, which occurs by splitting uranium atoms. The heat generated by nuclear fission creates heat, which in turn vaporizes water. The steam generated from this action spin turbines that generate electrical energy. Water is an integral tool in the production of nuclear energy. The vaporization of water is what actually generates the electrical energy within the process. The water used in this process can be recaptured for reuse. I thought that this would be important to point out in our exhibit.
However, nuclear energy is arguably unsustainable as the Earth’s uranium deposits will eventually deplete over time, but as long as nuclear waste produced by power stations are properly stored and secured, it can be considered to be a clean source of energy. Nuclear energy could serve as a very valuable form of energy production as we transition to more sustainable forms of energy and reduce our dependence on fossil fuels.
There are four nuclear power stations in South Carolina. The V.C. Summer Nuclear Generating Station, which was commissioned in 1973, and operated by the South Carolina Electric and Gas Company. (SCEG) The Oconee Nuclear Station, the Catawba Nuclear Station, and the Robertson Nuclear Plant are all owned and operated by Duke Energy and were commissioned between the 1970s and 1980s. (Duke Energy) The Oconee Nuclear Station is located in Seneca, SC and provides the Upstate with reliable energy.
Source: Duke Energy
It was opened in 1973 and uses 3 reactors. The type of reactor used by the station are pressurized water reactors. The station’s maximum capacity is 2,554 megawatts, which is enough energy to provide power 1.9 million homes. The nuclear station is the first nuclear station in the world to generate 100 million kilowatt hours of electricity.
It is the second nuclear power plant in the United States to have its operations license renewed by the Nuclear Regulatory Commission and it is the first nuclear station in the world to achieve 3 million safe work hours. South Carolina’s four nuclear power plants supplied about 58% of the state’s net electricity generation in 2017, and the state was the third-largest producer of nuclear power in the nation. Approximately 583.9 trillion Btu (British Thermal Units) of nuclear energy is produced and consumed in South Carolina. (EIA)
In the United States, the nuclear share of total U.S. electricity generating capacity was 9%, while the nuclear share of total electricity generation was about 20%. (EIA, 2017) There are 99 reactors operating in the US. 93% of the uranium that supplies US nuclear power plants are from foreign countries. The majority of the uranium that we import is from Canada and Australia at 35% and 20%, respectively.
Uranium is the element that fuels nuclear fission. Uranium is a common metal found in rocks all over the world. Uranium occurs in combination with small amounts of other elements. Economically recoverable uranium deposits have been discovered primarily in the western United States, Australia, Canada, Central Asia, Africa, and South America. (EIA) Nuclear power plants use a certain type of uranium, U-235, as fuel because its atoms are easily split apart. Although uranium is about 100 times more common than silver, U-235 is relatively rare. (EIA) After uranium is mined, the U-235 must be extracted and processed before it can be used as a fuel. Mined uranium ore typically yields one to four pounds of uranium concentrate (U3O8 or yellowcake) per ton, or 0.05% to 0.20% yellowcake. (EIA) Uranium is processed in uranium mills, and the process by which it is extracted and made into fuel can be seen in the image below.
Geothermal energy is heat derived below the earth’s surface which can be harnessed to generate clean, renewable energy. This vital, clean energy resource supplies renewable power around the clock and emits little or no greenhouse gases while requiring a small environmental footprint to develop. (DOE) Geothermal energy production has strong sustainability implications, as the rate of energy extraction can be balanced with a reservoir’s natural heat recharge rate. (DOE) Geothermal power plants also generate a small energy footprint, using less land per GWh (404 m2) than coal (3642 m2) wind (1335 m2) or solar PV with center station (3237 m2). (Geothermal Energy Administration) It is also notably clean, as modern closed-loop geothermal power plants emit no greenhouse gasses; life cycle GHG emissions (50 g CO2 eq/kWhe) are four times less than solar PV, and six to 20 times lower than natural gas. (Argonne National Lab) Geothermal power plants consume less water on average over the lifetime energy output than the most conventional generation technologies. (Argonne National Lab)
There are many methods by which geothermal energy can be generated, such as by dry steam plants. Dry steam plants use steam directly from a geothermal reservoir to turn generator turbines. The first geothermal power plant was built in 1904 in Tuscany, Italy, where natural steam erupted from the earth. (EIA) Flash steam plants take high-pressure hot water from deep inside the earth and convert it to steam to drive generator turbines. When the steam cools, it condenses to water and is injected back into the ground to be used again. Most geothermal power plants are flash steam plants. (Ibid.) Binary cycle power plants transfer the heat from geothermal hot water to another liquid. The heat causes the second liquid to turn to steam, which is used to drive a generator turbine. (Ibid.)
In Greenville, Geothermal heating and cooling is implemented at Furman University in Greenville, South Carolina. Underneath the parking lots located in the North Village apartment complex are a series of geothermal heat pumps, 10 of which were replaced in 2010. These highly efficient geothermal ground-source heat pumps, take advantage of the constant temperature of the earth to pre-heat or pre-cool air for ventilation. The project was paid for by a $2.5 million grant from the Department of Energy and matching funds from the university, and was completed in 2013. (Furman University) South Carolina, however does not have traditional sources of geothermal energy typically associated with the Western United States (geothermal power plants). (SC Energy Office) But, geothermal energy production accounts for 2% of all energy production in the US. (EIA)
Hydroelectric energy generation is a form of energy generation that is common in the United States. Because the source of hydroelectric power is water, hydroelectric power plants are usually located on or near a water source. The volume of the water flow and the change in elevation (or fall) from one point to another determine the amount of available energy in moving water. Swiftly flowing water in a big river, carries a great deal of energy in its flow. Water descending rapidly from a high point, also has substantial energy in its flow. (EIA)
Hydroelectric power is generated by water, which flows through a pipe, or penstock, and then pushes against and turns blades in a turbine to spin a generator to produce electricity. In a run-of-the-river system, the force of the current applies pressure on a turbine. In a storage system, water accumulates in reservoirs created by dams and is released as needed to generate electricity. (EIA) Hydroelectric power is a renewable source of energy that contributes to sustainability. While it is not lacking in issues related to the environment and human health, it is a method of obtaining (mostly) clean energy. Some of these issues are identified and addressed further on in this section.
An impoundment facility is the most common type of hydroelectric power plant. An impoundment facility, typically a large hydropower system, uses a dam to store river water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity. The water may be released either to meet changing electricity needs or to maintain a constant reservoir level. (DOE) A diversion, which is another way in which hydroelectric power is generated, is sometimes called a run-of-river facility, and it channels a portion of a river through a canal or penstock. It may not require the use of a dam. (DOE)
A pumped storage facility stores energy by pumping water uphill to a reservoir at higher elevation from a second reservoir at a lower elevation. When the demand for electricity is low, a pumped storage facility stores energy by pumping water from a lower reservoir to an upper reservoir. During periods of high electrical demand, the water is released back to the lower reservoir and turns a turbine, generating electricity. (DOE). These options, however, are not without their limitations. A dam that creates a reservoir (or a dam that diverts water to a run-of-river hydropower plant) may obstruct fish migration. Fish ladders provide a solution to this problem, but they cannot be retrofitted to all dams. (EIA)
A dam and reservoir can also change natural water temperatures, water chemistry, river flow characteristics, and silt loads. All of these changes can affect the ecology and the physical characteristics of the river. These changes may have negative effects on native plants and on animals in and around the river. (EIA) Reservoirs may cover important natural areas, agricultural land, or archeological sites. A reservoir and the operation of the dam may also result in the relocation of people. The physical impacts of a dam and reservoir, the operation of the dam, and the use of the water can change the environment over a much larger area than the area a reservoir covers. (EIA)
Manufacturing the concrete and steel in hydropower dams requires equipment that may produce emissions. If fossil fuels are the energy sources for making these materials, then the emissions from the equipment could be associated with the electricity that hydropower facilities generate. However, given the long operating lifetime of a hydropower plant (50 years to 100 years) these emissions are offset by the emissions-free hydroelectricity. (EIA) Greenhouse gases such as carbon dioxide and methane may also form in reservoirs and be emitted into the atmosphere. The exact amounts of greenhouse gases that form in hydropower reservoirs is uncertain. The greenhouse effect from the emissions from reservoirs in tropical and temperate regions, including the United States, may be equal to or greater than the greenhouse effect of the carbon dioxide emissions from an equivalent amount of electricity generation with fossil fuels. Scientists at Brazil’s National Institute for Space Research designed a system to capture methane in a reservoir and burn it to produce electricity. (EIA)
In South Carolina, 20.6 trillion Btu of hydroelectric power is produced and consumed per year. Bad Creek Hydroelectric Station is the highest-producing source of hydroelectricity in South Carolina. It is located in Oconee, South Carolina, and its maximum output is 1,065 MW of energy. It was commissioned in 1991 and is operated by Duke Energy. It provides energy for nearly 850,000 homes. (Duke Energy) Bad Creek Hydroelectric Station uses the flow of water to produce electricity. During times of peak demand, water is released from the Bad Creek Reservoir at the top of the mountain through a concrete tunnel that travels nearly three quarters of a mile to the underground powerhouse. The water then spins huge turbine generators to produce electricity. (Ibid.)
Source: Duke Energy
Before steam power and electricity were available in the United States, grain and lumber mills were powered directly with hydropower. (EIA) In 1900, hydroelectricity accounted for nearly 57% of the electricity generated within the United States. (SC Energy Office) Hydroelectricity accounted for about 7.5% of total U.S. utility-scale electricity generation and 44% of total utility-scale electricity generation from renewable energy sources. (EIA) Hydroelectricity’s share of total U.S. electricity generation has decreased over time, mainly because electricity generation from other sources has increased.
Every U.S. state has hydropower/hydroelectric facilities. Most hydroelectricity is produced at large dams built by the federal government, and many of the largest hydropower dams are in the western United States. (EIA) Many people associate dams with hydroelectric energy, however most dams were constructed for irrigation and flood control and do not have hydroelectricity generators. The U.S. Department of Energy (DOE) estimated that in 2012, non-powered dams in the United States had a total of 12,000 megawatts (MW) of potential hydropower capacity. (EIA) Perhaps this potential energy could be capitalized on through the use of microgenerators or retrofits?
A micro hydropower plant has a capacity of up to 100 kilowatts. A small or micro-hydroelectric power system can produce enough electricity for a home, farm, ranch, or village. Individuals could operate these for their own energy needs or to sell power to utilities. (Ibid.) This concept minimizes the negative effects associated with hydroelectric energy generation and damming, such as fish kills, and the displacement of water bodies, animal populations, and human populations, to name a few.
Solar energy is another sustainable source of energy, and there are three main methods by which solar energy can be collected. Linear concentrating systems are one way, solar power towers are another, and solar dish/engine systems are the third. Solar energy is a renewable energy source, as it it radiated from the Sun and is, essentially, limitless. This has great implications toward sustainability because it collects and provides energy in a safe and clean manner of which is safe to humans and the environment. Solar energy relates to water in that some solar power plants may require water for cleaning solar collectors and concentrators or for cooling turbine generators. Using large volumes of groundwater or surface water in some arid locations may affect the ecosystems that depend on these water resources. (EIA)
Linear concentrating systems collect the sun’s energy using long, rectangular, curved (U-shaped) mirrors. The mirrors focus sunlight onto receivers (tubes) that run the length of the mirrors. The concentrated sunlight heats a fluid flowing through the tubes. The fluid is sent to a heat exchanger to boil water in a conventional steam-turbine generator to produce electricity. There are two major types of linear concentrator systems: parabolic trough systems, where receiver tubes are positioned along the focal line of each parabolic mirror, and linear Fresnel reflector systems, where one receiver tube is positioned above several mirrors to allow the mirrors greater mobility in tracking the sun. (EIA)
Alternatively, a solar power tower system uses a large field of flat, sun-tracking mirrors called heliostats to reflect and concentrate sunlight onto a receiver on the top of a tower. Some power towers use water as the heat-transfer fluid. Advanced designs are experimenting with molten nitrate salt because of its superior heat transfer and energy storage capabilities. The thermal energy-storage capability allows the system to produce electricity during cloudy weather or at night. (EIA) Solar dish/engine systems use a mirrored dish similar to a very large satellite dish. The dish-shaped surface directs and concentrates sunlight onto a thermal receiver, which absorbs and collects the heat and transfers it to an engine generator. The most common type of heat engine used in dish/engine systems is the Stirling engine. This system uses the fluid heated by the receiver to move pistons and create mechanical power. The mechanical power runs a generator or alternator to produce electricity. (EIA)
Solar photovoltaic (PV) devices, or solar cells, change sunlight directly into electricity. Small cells, arrangements, and arrays can power, for example, watches, houses, or thousands of homes, respectively. (EIA)
Source: NASA
Alternatively, active solar heating systems use a collector and a fluid that absorbs solar radiation. Fans or pumps circulate air or heat-absorbing liquids through collectors and then transfer the heated fluid directly to a room or to a heat storage system. Active water heating systems usually have a tank for storing solar heated water. (EIA) Conversely, concentrating collectors focus or concentrate solar energy onto an absorber. The collector usually moves so that it maintains a high degree of concentration on the absorber. Solar thermal power plants use concentrating solar collector systems because they can produce high temperature heat. (EIA)
While solar energy is an abundant renewable energy source, the tools created to harvest it are not necessarily sustainable or safe. Some toxic materials and chemicals are used to make the photovoltaic (PV) cells that convert sunlight into electricity. Some solar thermal systems use potentially hazardous fluids to transfer heat. Leaks of these materials could be harmful to the environment. U.S. environmental laws regulate the use and disposal of these types of materials. (EIA) In addition, the beam of concentrated sunlight a solar power tower creates can kill birds and insects that fly into the beam. (EIA)
As mentioned before, Some solar power plants may require water for cleaning solar collectors and concentrators or for cooling turbine generators. Using large volumes of groundwater or surface water in some arid locations may affect the ecosystems that depend on these water resources. (EIA) And, clearing land for construction and the placement of the power plant may have long-term effects on the habitats of native plants and animals. (EIA) In Greenville County, there are a total of 2,537 solar energy installations. Of that amount, 1,172 of those installations are leased, and 1,365 are privately owned. (SC Energy Office)
In South Carolina, only 1 trillion Btu of solar energy is consumed per year. However, approximately 126 Btu is produced per year. (EIA) Duke Energy, South Carolina’s main energy provider provides a “net metering” service, in which consumers can offset their energy received by Duke Energy. Consumers can even negotiate to sell an excess amount of energy back to the company, however, there is a 2% cap on solar energy generation imposed by the state that is quickly being met. In the United States, only 1.3% of all energy produced per year (KWh/year) is produced by solar energy. (EIA)
Wind is another renewable energy source. Wind turbines do not release emissions that can pollute the air or water (with rare exceptions), and they do not require water for cooling. Wind turbines may also reduce the amount of electricity generation from fossil fuels, which results in lower total air pollution and carbon dioxide emissions. (EIA) An individual wind turbine has a relatively small physical footprint. Groups of wind turbines, sometimes called wind farms, are located on open land, on mountain ridges, or offshore in lakes or the ocean. (Ibid.)
Wind turbines harness the power of the wind and use it to generate electricity. Simply stated, a wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity. This illustration provides a detailed view of the inside of a wind turbine, its components, and their functionality. (DOE)
Modern wind turbines can be very large machines, and they may visually affect the landscape. A small number of wind turbines have also caught fire, and some have leaked lubricating fluids, but these occurrences are rare. Some people do not like the sound that wind turbine blades make as they turn in the wind. Some types of wind turbines and wind projects cause bird and bat deaths. These deaths may contribute to declines in the population of species also affected by other human-related impacts. The wind energy industry and the U.S. government are researching ways to reduce the effect of wind turbines on birds and bats. (EIA) Most wind power projects on land require service roads that add to the physical effects on the environment. Wind turbines may also use rare earth minerals. These minerals are often located in countries with less stringent environmental standards than the United States, and mining these minerals can have negative effects on the environment. Producing the metals and other materials used to make wind turbines and the concrete used for their foundations requires energy that may have been produced by fossil fuels. (Ibid.)
In South Carolina, experts agree that with some geographically isolated exceptions, such as the northwest corner of the state, wind power will only be a significant energy resource off the coast. (SC Office of Energy) Overall, in the US, colonists used windmills to grind grain, to pump water, and to cut wood at sawmills. Homesteaders and ranchers installed thousands of wind pumps as they settled the western United States. In the late 1800s and early 1900s, small wind-electric generators (turbines) were also widely used. When power lines were built to transmit electricity to rural areas in the 1930s, wind pump and small turbine use began to decline. However, some ranches still use wind pumps to supply water for livestock. Small wind turbines are becoming common again, mainly to supply electricity in remote and rural areas. (EIA) Today, wind energy accounts for 2% of renewable energy produced in the United States. (EIA)
Finally, fossil fuel products provide the US with a energy at the greatest to the environment. Crude oil is a mixture of hydrocarbons that formed from plants and animals that lived millions of years ago. Crude oil is a fossil fuel, and it exists in liquid form in underground pools or reservoirs, in tiny spaces within sedimentary rocks, and near the surface in tar (or oil) sands. Petroleum products are fuels made from crude oil and other hydrocarbons contained in natural gas. Petroleum products can also be made from coal, natural gas, and biomass. (EIA)
Wet natural gas is another fossil fuel and one of two forms of natural gasses. It is considered wet because it usually contains liquid hydrocarbons and non hydrocarbon gases. Methane and other useful gases are separated from the wet natural gas near the site of the well or at a natural gas processing plant. The processed natural gas is called dry or consumer-grade natural gas. This natural gas is sent through pipelines to underground storage fields or to distribution companies and then to consumers. (EIA)
Coal is a combustible black or brownish-black sedimentary rock with a high amount of carbon and hydrocarbons. Coal is classified as a nonrenewable energy source because it takes millions of years to form. Coal contains the energy stored by plants that lived hundreds of millions of years ago in swampy forests. Coal is classified into four main types, or ranks: anthracite, bituminous, subbituminous, and lignite. The ranking depends on the types and amounts of carbon the coal contains and on the amount of heat energy the coal can produce. The rank of a coal deposit is determined by the amount of pressure and heat that acted on the plants over time. (EIA)
Fossil fuels are harvested by using many techniques. Offshore Drilling is one of those techniques. Most of the energy the United States gets from the ocean is oil and natural gas from wells drilled on the ocean floor. Hydraulic fracturing is another common method of produces fractures in the rock formation that stimulate the flow of natural gas or oil, increasing the volumes that can be recovered. Wells may be drilled vertically hundreds to thousands of feet below the land surface and may include horizontal or directional sections extending thousands of feet. (EPA) Coal mining, extraction of coal deposits from the surface of Earth and from underground. Coal is the most abundant fossil fuel on Earth. Its predominant use has always been for producing heat energy. Since the mid-20th century, coal has yielded its place to petroleum and natural gas as the principal energy supplier of the world. (EB)
South Carolina only produces nuclear and small amounts of other renewable energies, totalling at 710.4 trillion Btu. (EIA) Consumption is another story, however. South Carolina consumes approximately 1 quadrillion Btu of fossil fuel energy per year. The United States leads the world in petroleum consumption at 19.88 million barrels per day as of 2017. (EIA) Coal is primarily used to generate electricity and is responsible for 30 percent of the electric power supply in the United States in 2017 (down from 39 percent in 2017 and 50 percent in 2007). (EIA)
Hydraulic fracturing, or fracking, is used to produce oil from shale and other tight geologic formations. Hydraulic fracturing has some effects on the environment. Fracturing rock requires large amounts of water, and it uses potentially hazardous chemicals to release the oil from the rock strata. In some areas of the country, significant water use for oil production may affect the availability of water for other uses and can potentially affect aquatic habitats. Faulty well construction or improper handling may result in leaks and spills of fracturing fluids. (EIA) Hydraulic fracturing also produces large amounts of wastewater that may contain dissolved chemicals and other contaminants. Wastewater is frequently disposed of by injection into deep wells, typically into saltwater aquifers. The injection of wastewater can cause earthquakes that may cause damage and are large enough to be felt. (Ibid.) The premise of “clean coal” has recently been promoted as a way to use this abundant energy source without damaging the environment. Carbon capture and storage (CCS) is a process in which carbon is separated from coal and injected underground for long term storage, could theoretically be used to mitigate the coal industry’s greenhouse gas emissions. However, CCS has yet to be proven as a safe or realistic way to reduce greenhouse gas emissions from commercial power plants and the environmental and health costs of mining remain. (EESI)
Natural gas, which is primarily composed of methane (CH4), is also generated by the decomposition of municipal waste in landfills and manure from livestock production. Methane is a greenhouse gas that is more than 20 times as potent as carbon dioxide. Capturing and burning the gas to produce usable heat and power prevents the methane from being released from the landfill or feedlot into the atmosphere directly. (Ibid.)
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