We consider biomass a renewable energy source, if the plants or other organic materials being burned are replaced. Biomass is known for its versatility , given it can be used to generate heat, electricity, be used in combined heat and power units and be used as liquid fuel. In domestic settings, it tends to be found in the form of wood-fuelled heating systems.
It is important to note, though, that biomass is only considered renewable if it comes from a sustainable source, where new plants are grown in place of those used for fuel.
On a large scale, biomass definitely produces lower emissions than burning coal. But no generation system is entirely zero carbon, and some biomass production systems are less sustainable than others. Biomass is most often co-fired in coal plants. Co-firing eliminates the need for new factories for processing biomass.
Co-firing also eases the demand for coal. This reduces the amount of carbon dioxide and other greenhouse gas es released by burning fossil fuels. Pyrolysis Pyrolysis is a related method of heating biomass. This keeps it from combusting and causes the biomass to be chemically altered. Pyrolysis produces a dark liquid called pyrolysis oil, a synthetic gas called syngas, and a solid residue called biochar. All of these components can be used for energy.
Pyrolysis oil , sometimes called bio-oil or biocrude, is a type of tar. It can be combusted to generate electricity and is also used as a component in other fuels and plastics.
Scientists and engineers are studying pyrolysis oil as a possible alternative to petroleum. Syngas can be converted into fuel such as synthetic natural gas. It can also be converted into methane and used as a replacement for natural gas. Biochar is a type of charcoal. Biochar is a carbon-rich solid that is particularly useful in agriculture. Biochar enriches soil and prevents it from leach ing pesticide s and other nutrients into runoff. Biochar is also an excellent carbon sink.
Carbon sink s are reservoirs for carbon-containing chemicals, including greenhouse gases. Gasification Biomass can also be directly converted to energy through gasification. The molecules break down, and produce syngas and slag. Syngas is a combination of hydrogen and carbon monoxide. During gasification, syngas is cleaned of sulfur, particulates, mercury, and other pollutants. The clean syngas can be combusted for heat or electricity, or processed into transportation biofuels, chemicals, and fertilizer s.
Slag forms as a glassy, molten liquid. It can be used to make shingles, cement, or asphalt. Industrial gasification plants are being built all over the world. Asia and Australia are constructing and operating the most plants, although one of the largest gasification plants in the world is currently under construction in Stockton-on-Tees, England.
This plant will eventually be able to convert more than , tons of MSW into enough energy to power 50, homes. Anaerobic Decomposition Anaerobic decomposition is the process where microorganisms, usually bacteria , break down material in the absense of oxygen. Anaerobic decomposition is an important process in landfill s, where biomass is crushed and compressed, creating an anaerobic or oxygen-poor environment.
In an anaerobic environment, biomass decay s and produces methane, which is a valuable energy source. This methane can replace fossil fuels. In addition to landfills, anaerobic decomposition can also be implemented on ranch es and livestock farms. Manure and other animal waste can be converted to sustainably meet the energy needs of the farm. Biofuel Biomass is the only renewable energy source that can be converted into liquid biofuels such as ethanol and biodiesel.
Biofuel is used to power vehicles, and is being produced by gasification in countries such as Sweden, Austria, and the United States. Ethanol is made by ferment ing biomass that is high in carbohydrates, such as sugar cane, wheat, or corn. Biodiesel is made from combining ethanol with animal fat, recycled cooking fat, or vegetable oil. Biofuels do not operate as efficiently as gasoline. However, they can be blended with gasoline to efficiently power vehicles and machinery, and do not release the emissions associated with fossil fuels.
Ethanol requires acres of farmland to grow biocrops usually corn. About 1, liters gallons of ethanol is produced by an acre of corn.
But this acreage is then unavailable for growing crops for food or other uses. Growing enough corn for ethanol also creates a strain on the environment because of the lack of variation in planting, and the high use of pesticides. Ethanol has become a popular substitute for wood in residential fireplaces.
When it is burned, it gives off heat in the form of flames, and water vapor instead of smoke. Biochar Biochar, produced during pyrolysis, is valuable in agricultural and environmental use. When biomass rots or burns naturally or by human activity , it releases high amounts of methane and carbon dioxide into the atmosphere. However, when biomass is charred, it sequester s, or stores, its carbon content. When biochar is added back to the soil, it can continue to absorb carbon and form large underground stores of sequestered carbon—carbon sinks—that can lead to negative carbon emissions and healthier soil.
Biochar also helps enrich the soil. It is porous. When added back to the soil, biochar absorbs and retains water and nutrients. Hydrocarbon Gas Liquids. Natural gas. Also in Hydrocarbon gas liquids explained Hydrocarbon gas liquids Where do hydrocarbon gas liquids come from? Transporting and storing Uses of hydrocarbon gas liquids Imports and exports Prices.
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Also in Coal explained Coal Mining and transportation Where our coal comes from Imports and exports How much coal is left Use of coal Prices and outlook Coal and the environment. Renewable sources. Renewable energy. Biofuels: Ethanol and Biomass-based diesel. Also in Hydropower explained Hydropower Where hydropower is generated Hydropower and the environment Tidal power Wave power Ocean thermal energy conversion. Also in Biofuels explained Biofuels Ethanol Use and supply of ethanol Ethanol and the environment Biomass-based diesel fuels Use of biomass-based diesel fuel Biomass-based diesel and the environment.
Also in Wind explained Wind Electricity generation from wind Where wind power is harnessed Types of wind turbines History of wind power Wind energy and the environment. Also in Geothermal explained Geothermal Where geothermal energy is found Use of geothermal energy Geothermal power plants Geothermal heat pumps Geothermal energy and the environment.
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Also in Hydrogen explained Hydrogen Production of hydrogen Use of hydrogen. Biomass—renewable energy from plants and animals Biomass is renewable organic material that comes from plants and animals. Wood, which makes up about half of all biomass employed for energy, has been used by people for thousands of years to cook food and to keep warm.
Grasses, agricultural crops such as corn and sugar cane , landfill waste, and manure are other examples of biomass. Used for a variety of purposes, biomass provides energy to produce electricity, heat, chemicals, and transportation fuels biofuels. It makes small contributions to each of the economic sectors, but the majority of this energy source goes to industry. The U. Energy Information Administration projects biomass generation to grow at an average of 4.
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