The Earth holds huge stocks of biorenewable and biomass resources covering wide regions of the planet, from fields, to forests, to the oceans. Already there is large scale production of energy crops around the world, including those that produce biofuels and biolubricants. Whether or not it is sustainable or viable to use such large areas of farmland and forests to produce dedicated energy crops has been the subject of much debate over the years as each crop must compete for arable farmland with existing uses and of course with each other.
Energy crops are defined as plants and crops grown specifically as an energy resource. The current production of biomass resources includes primarily agricultural byproducts, Herbaceous crops and forestry byproducts, woody biomass crops. But when agricultural crops are grown solely for their energy production, either as a biomass resource or as a biofuel, the plant species that offers the most efficiency and the least pollution potentials are usually selected.
Energy crops grown specifically as biomass resources include energy cane, sorghum, sugar cane, eucalyptus trees, switch grass, miscanthus, giant reeds, and leauceana lucacephala, etc. Dedicated energy crops can provide up to five or six times more potential energy than the amount of energy required to grow and produce them.
Energy crops can also be environmentally friendly with many of the plants grown as for biomass resources being advantageous to the environment. Dedicated energy crops contain significant quantities of one or more of four important energy-rich components: oils, sugars, starches, and fibre.
However, moisture content of the crop is a major factor when considering the use of a biomass feedstock, especially as energy. Biomass resources and herbaceous grasses which have lower moisture content at the time of harvesting have a major advantage that grass energy crops have over greener woodier energy crops.
Switchgrass and miscanthus form the primary production of herbaceous crops as these tropical grasses tend to grow faster than woody trees and can produce higher amounts of biomass feedstock in a much shorter period.
Generally the growth of these herbaceous plants usually lives for only a single growing season. Woody Energy Crops include hardwoods and softwoods form the basis of most biomass resources. The primary source of woody energy crops comes from fast growing trees and plantations, but woody biomass can also be a residue from forestry activities timber waste , from wood processing industrial wood, sawdust, wood shavings , and end-of-life wood products bulky waste, demolition, pallets.
Woody biomass is cut into uniform, small pieces called wood chips. Highly efficient and non-polluting burners and stoves can be designed to burn these chips for cooking and heating.
Lipids are water insoluble oils and fats obtained from recently living biomass. For example, soybean oil, palm oil, rapeseed oil, waxes and animal fats and greases, etc. Algae are among the fastest growing types organisms in the world, with about half of their weight being oil. The liquid biofuel, usually in the form of alcohol or ethanol, can be used to produce biodiesel to power cars, trucks, and even aeroplanes.
The carbon-neutrality of biomass resources made from energy crops relies on the new biomass balancing or at least outstripping the biomass grown for food.
Biomass is generally considered to be an excellent carbon sink with biomass feedstocks planted specifically as an energy crop, are likely to play a longer term role in providing sustainable sources for heating and power generation.
But land availability for growing food crops is becoming more scarce, so any competition for using fertile arable land to plant biomass energy crops should therefore be avoided. Besides, dedicated energy crops such as grasses, bamboo, reeds and canes are more appropriate for land unsuitable for agriculture. Home » WikiBiomass » Biomass resources.
Post navigation Previous post Editorial. Dedicated forestry. Short rotation plantations e. Forestry by-products. Wood blocks, wood chips from thinnings. Dry lignocellulosic energy crops. Herbaceous crops e. Oil, sugar and starch energy crops. Oil seeds for methylesters e. Sugar crops for ethanol e. Starch crops for ethanol e. Agricultural residues. Straw, prunings from vineyards and fruit trees. Learn more about biofuels. In addition to electricity and fuels, biomass can also be converted into chemicals for making plastics and other products that typically are made from petroleum.
The use of biomass energy has the potential to greatly reduce greenhouse gas emissions. Burning biomass releases about the same amount of carbon dioxide as burning fossil fuels.
However, fossil fuels release carbon dioxide captured by photosynthesis millions of years ago—an essentially "new" greenhouse gas. Biomass, on the other hand, releases carbon dioxide that is largely balanced by the carbon dioxide captured in its own growth depending how much energy was used to grow, harvest, and process the fuel.
However, studies have found that clearing forests to grow biomass results in a carbon penalty that takes decades to recoup, so it is best if biomass is grown on previously cleared land, such as under-utilized farmland. The use of biomass can reduce dependence on foreign oil because biofuels are the only renewable liquid transportation fuels available. Biomass energy supports U.
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