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Carbon-based Fuel
Carbon-based fuel is any fuel principally from the oxidation or burning of carbon. Carbon-based fuels are of two main kinds, biofuels and fossil fuels. Whereas biofuels are derived from recent-growth organic matter and are typically harvested, as with logging of forests and cutting of corn, fossil fuels are of prehistoric origin and are extracted from the ground, the principal fossil fuels being oil, coal, and natural gas. From an economic policy perspective, an important distinction between biofuels and fossil fuels is that only the former is sustainable or renewable. Whereas we can continue to obtain energy from biofuels indefinitely in principle, the Earth's reserves of fossil fuels was determined millions of years ago and is therefore fixed as far as our foreseeable future is concerned. The great variability in the ease of extraction of fossil fuels however makes its endgame scenario one of increasing prices over one or more centuries rather than of abrupt exhaustion. Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel
A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine. Other times, the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that accompanies combustion. Fuels are also used in the cells of organisms in a process known as cellular respiration, where organic molecules are oxidized to release usable energy. Hydrocarbons and related organic molecules are by far the most common source of fuel used by humans, but other substances, including radioactive metals, are also utilized. Fuels are contrasted with other substances or de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhouse Gas
A greenhouse gas (GHG or GhG) is a gas that Absorption (electromagnetic radiation), absorbs and Emission (electromagnetic radiation), emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Atmosphere of Earth, Earth's atmosphere are water vapor (), carbon dioxide (), methane (), nitrous oxide (), and ozone (). Without greenhouse gases, the average temperature of Earth#Surface, Earth's surface would be about , rather than the present average of . The atmospheres of atmosphere of Venus, Venus, atmosphere of Mars, Mars and atmosphere of Titan, Titan also contain greenhouse gases. Human activities since the beginning of the Industrial Revolution (around 1750) have increased the Carbon dioxide in Earth's atmosphere, atmospheric concentration of carbon dioxide by over 50%, from 280 parts per million, ppm in 1750 to 421 ppm in 2022. The last time the atmospheric concentration of carbon dioxide was this high was over 3&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofuels
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. According to the United States Energy Information Administration (EIA), biofuels are mostly used for transportation, but can also be used for heating and electricity. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste. The greenhouse gas mitigation potential of biofuel varies considerably, from emission levels comparable to fossil fuels in some scenarios to negative emissions in others. See the biomass article for more on this particular subject. The two most common types of biofuel are bioethanol and biodiesel. The U.S. is the largest producer of bioethanol, while the EU is the largest producer of biodiesel. The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively. * Bioethanol is an alcohol made by fermen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sustainability
Specific definitions of sustainability are difficult to agree on and have varied in the literature and over time. The concept of sustainability can be used to guide decisions at the global, national, and individual levels (e.g. sustainable living). Sustainability is commonly described as having three dimensions (also called pillars): environmental, economic, and social. Many publications state that the environmental dimension (also called "planetary integrity" or "ecological integrity") is the most important, and, in everyday usage, "sustainability" is often focused on countering major environmental problems, such as climate change, loss of biodiversity, loss of ecosystem services, land degradation, and air and water pollution. Humanity is now exceeding several "planetary boundaries". A closely related concept is that of sustainable development, and the terms are often used synonymously. However, UNESCO distinguishes the two thus: "''Sustainability'' is often thought of as a lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofuels
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. According to the United States Energy Information Administration (EIA), biofuels are mostly used for transportation, but can also be used for heating and electricity. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste. The greenhouse gas mitigation potential of biofuel varies considerably, from emission levels comparable to fossil fuels in some scenarios to negative emissions in others. See the biomass article for more on this particular subject. The two most common types of biofuel are bioethanol and biodiesel. The U.S. is the largest producer of bioethanol, while the EU is the largest producer of biodiesel. The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively. * Bioethanol is an alcohol made by fermen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wiki
A wiki ( ) is an online hypertext publication collaboratively edited and managed by its own audience, using a web browser. A typical wiki contains multiple pages for the subjects or scope of the project, and could be either open to the public or limited to use within an organization for maintaining its internal knowledge base. Wikis are enabled by wiki software, otherwise known as wiki engines. A wiki engine, being a form of a content management system, differs from other web-based systems such as blog software, in that the content is created without any defined owner or leader, and wikis have little inherent structure, allowing structure to emerge according to the needs of the users. Wiki engines usually allow content to be written using a simplified markup language and sometimes edited with the help of a rich-text editor. There are dozens of different wiki engines in use, both standalone and part of other software, such as bug tracking systems. Some wiki engines are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EERE
The Office of Energy Efficiency and Renewable Energy (EERE) is an office within the United States Department of Energy. Formed from other energy agencies after the 1973 energy crisis, EERE is led by the Assistant Secretary of Energy Efficiency and Renewable Energy (Assistant Secretary), who is appointed by the President of the United States and confirmed by the U.S. Senate. Kelly Speakes-Backman was appointed Acting Assistant Secretary in January 2021. Mission EERE’s mission is to drive the research, development, demonstration, and deployment of innovative technologies, systems, and practices that will (1) help transition Americans to a 100% clean energy economy no later than 2050 and (2) ensure the clean energy economy benefits all Americans. History EERE has been established from several previous agencies within the United States Executive branch following the 1973 energy crisis. It has foundations in the former agencies Federal Energy Administration, the Energy Research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types of air pollutants, such as gases (including ammonia, carbon monoxide, sulfur dioxide, nitrous oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both organic and inorganic), and biological molecules. Air pollution can cause diseases, allergies, and even death to humans; it can also cause harm to other living organisms such as animals and food crops, and may damage the natural environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for example, acid rain). Air pollution can be caused by both human activities and natural phenomena. Air pollution is a significant risk factor for a number of pollution-related diseases, including respiratory infections, heart disease, COPD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Monoxide
Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simplest molecule of the oxocarbon family. In coordination complexes the carbon monoxide ligand is called carbonyl. It is a key ingredient in many processes in industrial chemistry. The most common source of carbon monoxide is the partial combustion of carbon-containing compounds, when insufficient oxygen or heat is present to produce carbon dioxide. There are also numerous environmental and biological sources that generate and emit a significant amount of carbon monoxide. It is important in the production of many compounds, including drugs, fragrances, and fuels. Upon emission into the atmosphere, carbon monoxide affects several processes that contribute to climate change. Carbon monoxide has important biological roles across phylogenetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water – hence the name ''photosynthesis'', from the Greek ''phōs'' (), "light", and ''synthesis'' (), "putting together". Most plants, algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies most of the energy necessary for life on Earth. Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centers that contain green chlorophyll (and other colored) pigments/chromoph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and Earth's atmosphere, atmosphere of the Earth. Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone. Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to make Earth capable of sustaining life. It describes the movement of carbon as it is recycled and reused throughout the biosphere, as well as long-term processes of carbon sequestration to and release from carbon sinks. Carbon sinks in the land and the ocean each currently take up about one-quarter of anthropogenic carbon emissions each year. Humans have disturbed the biological carbon cycle for many centuries by modifying land use, and moreover with the recent industrial-scale mining of fossil carbon (coal, petroleum and natural gas, gas extraction, and cement manufacture) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Acidification
Ocean acidification is the reduction in the pH value of the Earth’s ocean. Between 1751 and 2021, the average pH value of the ocean surface has decreased from approximately 8.25 to 8.14. The root cause of ocean acidification is carbon dioxide emissions from human activities which have led to atmospheric carbon dioxide (CO2) levels of more than 410 ppm (in 2020). The oceans absorb CO2 from the atmosphere. This leads to the formation of carbonic acid (H2CO3) which dissociates into a bicarbonate ion () and a hydrogen ion (H+). The free hydrogen ions (H+) decrease the pH of the ocean, therefore increasing acidity (this does not mean that seawater is acidic yet; it is still alkaline, with a pH higher than 8). A decrease in pH corresponds to a decrease in the concentration of carbonate ions, which are the main building block for calcium carbonate (CaCO3) shells and skeletons. Marine calcifying organisms, like mollusks, oysters and corals, are particularly affected by this as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
