2018年10月2日星期二

Fossil fuel phase-out

Fossil fuel phase out refers to the discontinuation of the use of fossil fuels, through the decommissioning of operating fossil fuel-fired power plants, the prevention of the construction of new ones, and the use of alternative energy to replace the role of fossil fuels.

The purpose of fossil fuel phase-out is to reduce the negative externalities that use of fossil fuels cause. Negative externalities refer to the costs a certain activity has over people who did not choose to incur in them. A direct negative externality from fossil fuels' use is air pollution, and an indirect negative externality are mining accidents, that happen as a consequence of the extraction of fossil fuels. Fossil fuel burning contributes to climate change, as it releases greenhouse gas emissions.

Fossil fuels

Coal

Coal consumption trends 1980–2012 in the top five coal-consuming countries (US EIA)

Coal-fired power plants provided 30% of consumed electricity in the United States in 2016. This is the Castle Gate Plant near Helper, Utah.
Coal is one of the largest sources of energy, supplying 28.6% percent of the world's primary energy in 2014 (equivalent to 3,917 Mtoe) according to the International Energy Agency. Coal combustion accounted for 14,863 Mt of CO2 emissions in 2014, which is equivalent to a 45.9% of fossil fuel emissions from combustion (excluding non-energy emissions).

To decrease carbon emissions and thus possibly stop extreme climate change, some have called for coal to be phased out. Climatologist James E. Hansen said "We need a moratorium on coal now...with phase-out of existing plants over the next two decades." According to a study published in Science in 2017, coal has to be phased-out globally by about 2030, if the agreed 2 °C target is taken seriously.

Some nations have decreased their coal consumption thus far in the 21st century, the greatest reductions being in the United States (coal consumption reduced by 176 million metric tons per year over the period 2000-2012), Canada (reduced by 21 million tons per year) and Spain (20 million tons per year). Other nations have increased their coal consumption in the same period, led by China (increased 2,263 million metric tons per year in the period 2000-2012), India (increased 367 million tons per year), and South Korea (59 million tons per year). Worldwide, coal consumption increased 60% during the period 2000-2012. As of 2012, 1200 new coal power plants were reportedly being planned worldwide, most of them in China and India. In the 2011-2013 period, the OECD group of Western European countries has increased the use of coal, attributed largely to the low cost of coal and the high price of imported natural gas in Western Europe. However, coal consumption has peaked in China in 2013 or 2014, depending on the data used and fell in 2015 by 3.6%, even though there was a growth of GDP of 6.9%. Worldwide coal consumption peaked in 2014 and declined in 2015 and 2016.

According to Scientific American, the average coal plant emits more than 100 times as much radiation per year than does a comparatively sized nuclear power plant, in the form of fly ash.

Some like the "coal advisory board" of the IEA believe that coal should not be phased out, considering that longer-term global economic growth cannot be achieved without adequate and affordable energy supplies, which will require continuing significant contributions from fossil fuels including coal. In this viewpoint, clean coal technology could reduce greenhouse gas emissions compatible with a low-emissions future. Some environmentalists and climatologists support a phase-out and criticise clean coal as not a solution to climate change. Entrepreneurs promote improved regulations and modernised technology. Sometimes coal is replaced by natural gas, which has lower carbon emissions and produces less pollutants. However natural gas is also a fossil fuel, so a switch from coal to natural gas does not contribute to a fossil fuel phase-out.

As of September 2018, 28 national governments, 18 sub-national governments and 28 organisations had become members of the Powering Past Coal Alliance, each making a declaration to advance the transition away from unabated* coal power generation.

Oil
Oil is refined into fuel oil, diesel and gasoline. The refined products are primarily for transportation by conventional cars, trucks, trains, planes and ships. Popular alternatives are Human-powered transport, public transport, electric vehicles, and biofuels.

Natural gas
Although natural gas has about half the carbon intensity of coal it is also the single largest source of atmospheric methane in the United States. It is seen by many as a temporary "bridge fuel" to replace coal, but in turn to be replaced by renewable sources. However this "bridge fuel" is likely to significantly extend the use of fossil fuel as the average plant life is 35 years. Gas consumption has tripled since 1971, and by 2015 it was generating half as much electricity as coal. Since the consumption of gas is expected to grow an additional 10% by 2040, the phase out is likely to be many years in the future.

Basis
The basis of phasing-out fossil fuels consists mainly of the projected lower cost of renewable sources of energy, but the avoidance of risks in health and mitigation of global warming are also important considerations.

Health
Using computer modeling he developed over 20 years, Mark Z. Jacobson has found that carbonaceous fuel soot emissions (which lead to respiratory illness, heart disease, and asthma) have resulted in 1.5 million premature deaths each year, mostly in the developing world where the non-fossil fuels wood and animal dung are used for cooking. Jacobson has also said that soot from diesel engines, coal-fired power plants, and burning wood is a "bigger cause of global warming than previously thought, and is the major cause of the rapid melting of the Arctic's sea ice".

In 2011, new evidence has emerged that there are considerable risks associated with traditional energy sources, and that major changes to the mix of energy technologies are needed:

Several mining tragedies globally have underscored the human toll of the coal supply chain. New EPA initiatives targeting air toxics, coal ash, and effluent releases highlight the environmental impacts of coal and the cost of addressing them with control technologies. The use of fracking in natural gas exploration is coming under scrutiny, with evidence of groundwater contamination and greenhouse gas emissions. Concerns are increasing about the vast amounts of water used at coal-fired plants, particularly in regions of the country facing water shortages.

Global warming mitigation
In 2008, James Hansen and nine other scientists published a journal article titled "Target atmospheric CO2: Where should humanity aim?" which calls for a complete phase-out of coal power by 2030.

More recently, Hansen has stated that continued opposition to nuclear power threatens humanity's ability to avoid dangerous climate change. The letter, co-authored with other climate change experts declared "If we stay on the current path," he said, "those are the consequences we'll be leaving to our children. The best candidate to avoid that is nuclear power. It's ready now. We need to take advantage of it." and "Continued opposition to nuclear power threatens humanity's ability to avoid dangerous climate change."

Also in 2008, Pushker Kharecha and James Hansen published a peer-reviewed scientific study analyzing the effect of a coal phase-out on atmospheric carbon dioxide (CO2) levels. Their baseline mitigation scenario was a phaseout of global coal emissions by 2050. The authors describe the scenario as follows:

The second scenario, labeled Coal Phase-out, is meant to approximate a situation in which developed countries freeze their CO2 emissions from coal by 2012 and a decade later developing countries similarly halt increases in coal emissions. Between 2025 and 2050 it is assumed that both developed and developing countries will linearly phase out emissions of CO2 from coal usage. Thus in Coal Phase-out we have global CO2 emissions from coal increasing 2% per year until 2012, 1% per year growth of coal emissions between 2013 and 2022, flat coal emissions for 2023–2025, and finally a linear decrease to zero CO2 emissions from coal in 2050. These rates refer to emissions to the atmosphere and do not constrain consumption of coal, provided the CO2 is captured and sequestered. Oil and gas emissions are assumed to be the same as in the BAU [business as usual] scenario.

Kharecha and Hansen also consider three other mitigation scenarios, all with the same coal phase-out schedule but each making different assumptions about the size of oil and gas reserves and the speed at which they are depleted. Under the Business as Usual scenario, atmospheric CO2 peaks at 563 parts per million (ppm) in the year 2100. Under the four coal phase-out scenarios, atmospheric CO2 peaks at 422-446 ppm between 2045 and 2060 and declines thereafter. The key implications of the study are as follows: a phase-out of coal emissions is the most important remedy for mitigating human-induced global warming; actions should be taken toward limiting or stretching out the use of conventional oil and gas; and strict emissions-based constraints are needed for future use of unconventional fossil fuels such as methane hydrates and tar sands.

Others
The impulse of renewable energy can create jobs through the construction of new power plants and the manufacturing of the equipment that they need, as could be seen in the case of Germany and the wind power industry.

Studies about fossil fuel phase-out
In the Greenpeace and EREC's Energy (R)evolution scenario, the world would eliminate all fossil fuel use by 2090.

In December 2015 Greenpeace and Climate Action Network Europe released a report highlighting the need for an active phase-out of coal-fired generation across Europe. Their analysis derived from a database of 280 coal plants and included emissions data from official EU registries.

A September 2016 report by Oil Change International concludes that the carbon emissions embedded in the coal, oil, and gas in currently working mines and fields, assuming that these run to the end of their working lifetimes, will take the world to just beyond the 2 °C limit contained in the 2015 Paris Agreement and even further from the 1.5 °C goal. The report observes that "one of the most powerful climate policy levers is also the simplest: stop digging for more fossil fuels".:5

In October 2016, the Overseas Development Institute (ODI) and 11 other NGOs released a report on the impact of building new coal-fired power plants in countries where a significant proportion of the population lacks access to electricity. The report concludes that, on the whole, building coal-fired power plants does little to help the poor and may make them poorer. Moreover, wind and solar generation are beginning to challenge coal on cost.

A 2018 study in Nature Energy suggests that 10 countries in Europe could completely phase out coal-fired electricity generation with their current infrastructure, whilst the US and Russia could phase out at least 30%.

Challenges of fossil fuel phase-out
The phase-out of fossil fuels involves many challenges, and one of them is the reliance that currently the world has on them. In 2014, fossil fuels provided 81.1% of the primary energy consumption of the world, with approximately 11,109 Mtoe. This number is composed by 4,287 Mtoe of oil consumption; 3,918 Mtoe of coal consumption, and 2,904 Mtoe of natural gas consumption .

Fossil fuel phase-out can lead to an increment in electricity prices, because of the new investments needed to replace their share in the electricity mix with alternative energy sources. Another cause to increasing electricity price comes from the need to import the electricity that can't be generated nationally.

Another impact of a phase-out of fossil fuels is in the employment. In the case of employments in the fossil fuel industry, a phase-out is logically undesired, therefore, people in the industry will usually oppose any measures that put their industries under scrutiny. Endre Tvinnereim and Elisabeth Ivarsflaten studied the relationship between employment in the fossil fuel industry with the support to climate change policies. They proposed that one opportunity for displaced drilling employments in the fossil fuel industry could be in the geothermal energy industry. This was suggested as a result of their conclusion: people and companies in the fossil fuel industry will likely oppose measures that endanger their employments, unless they have other stronger alternatives. This can be extrapolated to political interests, that can push against the phase-out of fossil fuels initiative. One example is how the vote of U.S. Congress members is related to the preeminence of fossil fuel industries in their respective states.

Legislation and initiatives to phase out coal
In 8 June 2015, several newspapers ran an article wrote that the leaders of the Group of Seven (or G7, consisting of Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States) agreed to phase-out fossil fuel use by 2100, as part of the efforts to keep global temperature increase under 2 °C. This was done as a prelude for the United Nations Climate Change Conference (a.k.a. COP 21) hosted in Paris, on December of the same year.

Public opinion

Opinion polls

Opinion research
In October, 2007, Civil Society Institute released the results of a poll of 1,003 U.S. citizens conducted by Opinion Research Corporation.

The authors of the poll reported: "75 percent of Americans—including 65 percent of Republicans, 83 percent of Democrats and 76 percent of Independents—would 'support a five-year moratorium on new coal-fired power plants in the United States if there was stepped-up investment in clean, safe renewable energy—such as wind and solar—and improved home energy-efficiency standards.' Women (80 percent) were more likely than men (70 percent) to support this idea. Support also was higher among college graduates (78 percent) than among those who did not graduate from high school (68 percent)."

The exact question posed by the survey was as follows: More than half of power plant-generated electricity comes from coal. Experts say that power plants are responsible for about 40 percent of U.S. carbon dioxide pollution linked to global warming. There are plans to build more than 150 new coal-fired power plants over the next several years. Would you support a five-year moratorium on new coal-fired power plants in the United States if there was stepped-up investment in clean, safe and renewable energy—such as wind and solar—and improved home energy-efficiency standards? Would you say definitely yes, probably yes, probably no, definitely no, or don't know.

The results were as follows:

30% "definitely yes"
45% "probably yes"
13% "probably no"
8% "definitely no"
4% "don't know"

Gallup
In 2013, the Gallup organization determined that 41% of Americans wanted less emphasis placed on coal energy, versus 31% who wanted more. Large majorities wanted more emphasis placed on solar (76%), wind (71%), and natural gas (65%).

ABC News/Washington Post
A 2009 ABC/Washington Post poll found 52% of Americans favored more coal mining (33% strongly favored), while 45% opposed (27% strongly opposed). The most support was for wind and solar, which were favored by 91% (79% strongly favored).

CLEAN call to action
In October, 2007, fifteen groups led by Citizens Lead for Energy Action Now (CLEAN) called for a five-year moratorium on new coal-fired power plants, with no exception for plants sequestering carbon. The groups included Save Our Cumberland Mountains (Tennessee); Ohio Valley Environmental Council (West Virginia); Cook Inlet Keeper (Alaska); Christians for the Mountains (West Virginia); Coal River Mountain Watch (West Virginia); Kentuckians for the Commonwealth (Kentucky); Civil Society Institute (Massachusetts); Clean Power Now (Massachusetts); Indigenous Environmental Network (Minnesota); Castle Mountain Coalition (Alaska); Citizens Action Coalition (Indiana); Appalachian Center for the Economy & the Environment (West Virginia); Appalachian Voices (NC); and Rhode Island Wind Alliance (Rhode Island).

Environmental Defense Fund
The US-based Environmental Defense Fund (EDF) has taken a stand in favor of natural gas production and hydraulic fracturing, while pressing for stricter environmental controls on gas drilling, as a feasible way to replace coal. The organization has funded studies jointly with the petroleum industry on the environmental effects of natural gas production. The organization sees natural gas as a way to quickly replace coal, and that natural gas in time will be replaced by renewable energy. The policy has been criticized by some environmentalists. EDF counsel and blogger Mark Brownstein answered:

Other groups supporting a coal moratorium
1Sky
Co-op America
Energy Action Coalition
Kansas Sierra Club
Lead for Energy Action Now (CLEAN)
Rainforest Action Network
Rising Tide Australia
Sierra Club
SixDegrees.org
Step It Up! 2007

Shareholder resolutions in favor of a coal moratorium
Trillium Asset Management, a social investment management company, submitted the resolution "Moratorium on Coal Financing" to Bank of America in the 2007–2008 shareholder resolution season. The resolution concluded:
RESOLVED: Shareholders request that BOA's board of directors amend its GHG emissions policies to observe a moratorium on all financing, investment and further involvement in activities that support MTR coal mining or the construction of new coal-burning power plants that emit carbon dioxide.

Local governments supporting a coal moratorium
In January, 2008, Black Hawk County (Iowa) Health Board recommended that the state adopt a moratorium on new coal-fired power plants until it enacts tougher air pollution standards.

Alternative Sources of Energy
Alternative energy refers to any source of energy that can substitute the role of fossil fuels. Renewable energy, or energy that is harnessed from renewable sources, is an alternative energy. However, alternative energy can refer to non renewable sources as well, like nuclear energy. Between the alternative sources of energy are: solar energy, hydroelectricity, marine energy, wind energy, geothermal energy, biofuels, ethanol and Hydrogen.

Energy efficiency is complementary to the use of alternative energy sources, when phasing-out fossil fuels.

Renewable energy
Renewable energy is energy that comes from resources which are naturally replenished such as sunlight, wind, rain, tides, waves, and geothermal heat. As of 2014, 19% of global final energy consumption comes from renewable resources, with 9% of all energy from traditional biomass, mainly used for heating, 1% from biofuels, 4% from hydroelectricity and 4% from biomass, geothermal or solar heat . Popular renewables (wind, solar, geothermal and biomass for power) accounted for another 1.4% and are growing rapidly. While renewable energy supplies are growing and have displaced coal in some regions, the amount of coal burned in 2021, is expected to be the same as it was in 2014.

Hydroelectricity
In 2015 hydroelectric energy generated 16.6% of the worlds total electricity and 70% of all renewable electricity. In Europe and North America environmental concerns around land flooded by large reservoirs ended 30 years of dam construction in the 1990s. Since then large dams and reservoirs continue to be built in countries like China, Brazil and India. Run-of-the-river hydroelectricity and small hydro have become popular alternatives to conventional dams that may create reservoirs in environmentally sensitive areas.

Wind power
A wind farm is a group of wind turbines in the same location used to produce electric power. A large wind farm may consist of several hundred individual wind turbines, and cover an extended area of hundreds of square miles, but the land between the turbines may be used for agricultural or other purposes. A wind farm may also be located offshore.

Wind power has grown dramatically since 2005 and by 2015 supplied almost 1% of global energy consumption.

Many of the largest operational onshore wind farms are located in the United States and China. The Gansu Wind Farm in China has over 5,000 MW installed with a goal of 20,000 MW by 2020. China has several other "wind power bases" of similar size. The Alta Wind Energy Center in California, United States is the largest onshore wind farm outside of China, with a capacity of 1020 MW of power. As of February 2012, the Walney Wind Farm in the United Kingdom is the largest offshore wind farm in the world at 367 MW, followed by Thanet Offshore Wind Project (300 MW), also in the United Kingdom. As of February 2012, the Fântânele-Cogealac Wind Farm in Romania is the largest onshore wind farm in Europe at 600 MW.

There are many large wind farms under construction and these include Sinus Holding Wind Farm (700 MW), Anholt Offshore Wind Farm (400 MW), BARD Offshore 1 (400 MW), Clyde Wind Farm (350 MW), Greater Gabbard wind farm (500 MW), Lincs Wind Farm (270 MW), London Array (1000 MW), Lower Snake River Wind Project (343 MW), Macarthur Wind Farm (420 MW), Shepherds Flat Wind Farm (845 MW), and Sheringham Shoal (317 MW).

Wind power in Denmark produced the equivalent of 42.1% of total electricity consumption in 2015, however, use of wind for heating is minor.

Solar
By 2020 the solar contribution to global final energy consumption will exceed 1%.

Solar photovoltaics
Solar photovoltaic cells convert sunlight into electricity and many solar photovoltaic power stations have been built. The size of these stations has increased progressively over the last decade with frequent new capacity records.

As of January 2013, the largest individual photovoltaic (PV) power plants in the world are Agua Caliente Solar Project, (Arizona, over 247 MW connected - to increase to 397 MW), Golmud Solar Park (China, 200 MW), Mesquite Solar project (Arizona, 150 MW), Neuhardenberg Solar Park (Germany, 145 MW), Templin Solar Park (Germany, 128 MW), Toul-Rosières Solar Park (France, 115 MW), and Perovo Solar Park (Ukraine, 100 MW). The Charanka Solar Park is a collection of solar power stations of which 214 MW were reported complete in April 2012, on a 2000 ha site. It is part of Gujarat Solar Park, a group of solar farms at various locations in the Gujarat state of India, with overall capacity of 702 MW. There are a total of 570 MW of solar parks in Golmud, with 500 MW more expected in 2012.

Many large plants are under construction. The Desert Sunlight Solar Farm is a 550 MW solar power plant under construction in Riverside County, California, that will use thin-film solar photovoltaic modules made by First Solar. The Topaz Solar Farm is a 550 MW photovoltaic power plant, being built in San Luis Obispo County, California. The Blythe Solar Power Project is a 500 MW photovoltaic station under construction in Riverside County, California. The Agua Caliente Solar Project is a 290 megawatt photovoltaic solar generating facility being built in Yuma County, Arizona. The California Valley Solar Ranch (CVSR) is a 250 megawatt (MW) solar photovoltaic power plant, which is being built by SunPower in the Carrizo Plain, northeast of California Valley. The 230 MW Antelope Valley Solar Ranch is a First Solar photovoltaic project which is under construction in the Antelope Valley area of the Western Mojave Desert, and due to be completed in 2013.

Many of these plants are integrated with agriculture and some use innovative tracking systems that follow the sun's daily path across the sky to generate more electricity than conventional fixed-mounted systems. Solar power plants have no fuel costs or emissions during operation.

Concentrated solar power
Concentrating Solar Power (CSP) systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. The concentrated heat is then used as a heat source for a conventional power plant. A wide range of concentrating technologies exists; the most developed are the parabolic trough, the concentrating linear fresnel reflector, the Stirling dish and the solar power tower. Various techniques are used to track the Sun and focus light. In all of these systems a working fluid is heated by the concentrated sunlight, and is then used for power generation or energy storage.

Biofuels
Biofuels, in the form of liquid fuels derived from plant materials, are entering the market. However, many of the biofuels that are currently being supplied have been criticised for their adverse impacts on the natural environment, food security, and land use.

Biomass
Biomass is biological material from living, or recently living organisms, most often referring to plants or plant-derived materials. As a renewable energy source, biomass can either be used directly, or indirectly—once or converted into another type of energy product such as biofuel. Biomass can be converted to energy in three ways: thermal conversion, chemical conversion, and biochemical conversion.

Using biomass as a fuel produces air pollution in the form of carbon monoxide, carbon dioxide, NOx (nitrogen oxides), VOCs (volatile organic compounds), particulates and other pollutants at levels above those from traditional fuel sources such as coal or natural gas in some cases (such as with indoor heating and cooking). Utilization of wood biomass as a fuel can also produce fewer particulate and other pollutants than open burning as seen in wildfires or direct heat applications. Black carbon – a pollutant created by combustion of fossil fuels, biofuels, and biomass – is possibly the second largest contributor to global warming.:56–57 In 2009 a Swedish study of the giant brown haze that periodically covers large areas in South Asia determined that it had been principally produced by biomass burning, and to a lesser extent by fossil fuel burning. Denmark has increased the use of biomass and garbage, and decreased the use of coal.

Nuclear energy
The 2014 Intergovernmental Panel on Climate Change report identifies nuclear energy as one of the technologies that can provide electricity with less than 5% of the lifecycle greenhouse gas emissions of coal power. There are more than 60 nuclear reactors shown as under construction in the list of Nuclear power by country with China leading at 23. Globally, more nuclear power reactors have closed than opened in recent years but overall capacity has increased. China has stated its plans to double nuclear generation by 2030. India also plans to greatly increase its nuclear power.

Several countries have enacted laws to cease construction on new nuclear power stations. Several European countries have debated nuclear phase-outs and others have completely shut down some reactors. Three nuclear accidents have influenced the slowdown of nuclear power: the 1979 Three Mile Island accident in the United States, the 1986 Chernobyl disaster in the USSR, and the 2011 Fukushima nuclear disaster in Japan. Following the March 2011 Fukushima nuclear disaster, Germany has permanently shut down eight of its 17 reactors and pledged to close the rest by the end of 2022. Italy voted overwhelmingly to keep their country non-nuclear. Switzerland and Spain have banned the construction of new reactors. Japan’s prime minister has called for a dramatic reduction in Japan’s reliance on nuclear power. Taiwan’s president did the same. Shinzō Abe, the new prime minister of Japan since December 2012, announced a plan to restart some of the 54 Japanese nuclear power plants and to continue some nuclear reactors under construction.

As of 2016, countries such as Australia, Austria, Denmark, Greece, Malaysia, New Zealand, and Norway have no nuclear power stations and remain opposed to nuclear power. Germany, Italy, Spain and Switzerland are phasing-out their nuclear power.

Energy efficiency
Moving away from fossil fuels will require changes not only in the way energy is supplied, but in the way it is used, and reducing the amount of energy required to deliver various goods or services is essential. Opportunities for improvement on the demand side of the energy equation are as rich and diverse as those on the supply side, and often offer significant economic benefits.

A sustainable energy economy requires commitments to both renewables and efficiency. Renewable energy and energy efficiency are said to be the "twin pillars" of sustainable energy policy. The American Council for an Energy-Efficient Economy has explained that both resources must be developed in order to stabilize and reduce carbon dioxide emissions:

Efficiency is essential to slowing the energy demand growth so that rising clean energy supplies can make deep cuts in fossil fuel use. If energy use grows too fast, renewable energy development will chase a receding target. Likewise, unless clean energy supplies come online rapidly, slowing demand growth will only begin to reduce total emissions; reducing the carbon content of energy sources is also needed.

The IEA has stated that renewable energy and energy efficiency policies are complementary tools for the development of a sustainable energy future, and should be developed together instead of being developed in isolation.

Source from Wikipedia

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