Renewable Energy. What is Biomass? Some examples of materials that make up biomass fuels are: scrap lumber; forest debris; certain crops; manure; and some types of waste residues.
Biomass is a renewable source of fuel to produce energy because: waste residues will always exist — in terms of scrap wood, mill residuals and forest resources; and properly managed forests will always have more trees, and we will always have crops and the residual biological matter from those crops. What is biomass power? Biomass challenges While the process to create electricity is similar whether using a biomass fuel or a fossil fuel, the equipment needed inside the plant is different.
Biomass and the US Biomass fuels provided about 4 percent of the energy used in the United States in What is Biomass Biomass power is clean, green energy. The electric power sector uses wood and biomass-derived wastes to generate electricity for sale to the other sectors. Biomass explained.
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Also in Gasoline explained Gasoline Octane in depth Where our gasoline comes from Use of gasoline Prices and outlook Factors affecting gasoline prices Regional price differences Price fluctuations History of gasoline Gasoline and the environment. 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. This enhances the soil and leads to significantly higher plant growth. Black Liquor When wood is processed into paper, it produces a high-energy, toxic substance called black liquor.
Until the s, black liquor from paper mills was considered a waste product and dumped into nearby water sources. With the invention of the recovery boiler in the s, black liquor could be recycled and used to power the mill. In the U. More recently, Sweden has experimented in gasifying black liquor to produce syngas, which can then be used to generate electricity. Hydrogen Fuel Cells Biomass is rich in hydrogen, which can be chemically extracted and used to generate power and to fuel vehicles.
Stationary fuel cells are used to generate electricity in remote locations, such as spacecraft and wilderness areas. Yosemite National Park in the U. Hydrogen fuel cells may hold even more potential as an alternative energy source for vehicles. The U. Department of Energy estimates that biomass has the potential to produce 40 million tons of hydrogen per year. This would be enough to fuel million vehicles. Currently, hydrogen fuel cells are used to power buses, forklifts, boats, and submarines, and are being tested on airplanes and other vehicles.
However, there is a debate as to whether this technology will become sustainable or economically possible.
The energy that it takes to isolate, compress, package, and transport the hydrogen does not leave a high quantity of energy for practical use. The carbon cycle is the process by which carbon is exchanged between all layers of the Earth: atmosphere , hydrosphere , biosphere , and lithosphere. The carbon cycle takes many forms. It is exchanged through photosynthesis, decomposition, respiration, and human activity.
Carbon that is absorbed by soil as an organism decomposes, for example, may be recycled as a plant releases carbon-based nutrients into the biosphere through photosynthesis. Under the right conditions, the decomposing organism may become peat , coal, or petroleum before being extract ed through natural or human activity. Between periods of exchange, carbon is sequestered, or stored.
The carbon in fossil fuels has been sequestered for millions of years. When fossil fuels are extracted and burned for energy, their sequestered carbon is released into the atmosphere. Fossil fuels do not re-absorb carbon. In contrast to fossil fuels, biomass comes from recently living organisms.
The carbon in biomass can continue to be exchanged in the carbon cycle. In order to effectively allow Earth to continue the carbon cycle process, however, biomass materials such as plants and forests have to be sustainably farmed. It takes decades for trees and plants such as switchgrass to re-absorb and sequester carbon. Uprooting or disturbing the soil can be extremely disruptive to the process. A steady and varied supply of trees, crops, and other plants is vital for maintaining a healthy environment.
Algal Fuel Algae is a unique organism that has enormous potential as a source of biomass energy. Algae, whose most familiar form is seaweed , produces energy through photosynthesis at a much quicker rate than any other biofuel feedstock—up to 30 times faster than food crops! Algae can be grown in ocean water, so it does not deplete freshwater resources. It also does not require soil, and therefore does not reduce arable land that could potentially grow food crops.
Although algae releases carbon dioxide when it is burned, it can be farmed and replenished as a living organism. As it is replenished, it releases oxygen, and absorbs pollutant s and carbon emissions. Algae takes up much less space than other biofuel crops. Examples include corn stover stalks, leaves, husks, and cobs , wheat straw, oat straw, barley straw, sorghum stubble, and rice straw. The sale of these residues to a local biorefinery also represents an opportunity for farmers to generate additional income.
Forestry Residues Forest biomass feedstocks fall into one of two categories: forest residues left after logging timber including limbs, tops, and culled trees and tree components that would be otherwise unmerchantable or whole-tree biomass harvested explicitly for biomass.
Dead, diseased, poorly formed, and other unmerchantable trees are often left in the woods following timber harvest. This woody debris can be collected for use in bioenergy, while leaving enough behind to provide habitat and maintain proper nutrient and hydrologic features.
There are also opportunities to make use of excess biomass on millions of acres of forests. Harvesting excessive woody biomass can reduce the risk of fire and pests, as well as aid in forest restoration, productivity, vitality, and resilience.
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