Biomass is biological material from living, or recently living organisms, most often referring to plants or plant-derived materials.^[1] 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.
Historically, humans have harnessed biomass derived energy products since the time when people began burning wood to make fire.^[2] In modern times, the term can be referred to in two meanings. In the first sense, biomass is plant matter used either to generate electricity (via steam turbines or gasifiers), or to produce heat (via direct combustion). Wood remains the largest biomass energy source today;^[2] examples include forest residues (such as dead trees, branches and tree stumps), yard clippings, wood chips and even municipal solid waste. In the second sense, biomass includes plant or animal matter that can be converted into fibers or other industrial chemicals, including biofuels. Industrial biomass can be grown from numerous types of plants, including miscanthus, switchgrass, hemp, corn, poplar, willow, sorghum, sugarcane, bamboo,^[3] and a variety of tree species, ranging from eucalyptus to oil palm (palm oil).
The adoption of biomass-based energy plants has been a slow but steady process. Over the past decade, the production of these plants has increased 14%.^[4] In the United States, alternative electricity-production sources on the whole generate about 13% of power; of this fraction, biomass contributes approximately 11% of the alternative production.^[5] According to a study conducted in early 2012, of the 107 operating biomass plants in the United States, 85 have been cited by federal or state regulators for the violation of clean air or water standards laws over the past 5 years. This data also includes minor infractions.^[4]
Biomass mass derived energy also holds the promise of reducing carbon dioxide emissions, a significant contributor to global warming, carbon dioxide acts as a “greenhouse” gas by trapping heat absorbed by the earth from the sun. Although the burning of biomass energy releases as much carbon dioxide as fossil fuels, biomass burning does not release “new carbon” into the atmosphere while burning fossil fuels does.^[6] This is because carbon dioxide released from fossil fuels was carbon that was fixated via photosynthesis millions of years ago that had been locked in the hydrocarbons of fossil fuels.^[6]
Industry professionals claim that a range of issues can affect a plant’s ability to comply with emissions standards. Some of these challenges, unique to biomass plants, include inconsistent fuel supplies and age. The type and amount of the fuel supply is completely reliant factors; the fuel can be in the form of building debris or agricultural waste (such as deforestation of invasive species or orchard trimmings). Furthermore, many of the biomass plants are old, use outdated technology and were not built to comply with today’s stringent standards. In fact, many are based on technologies developed during the term of President Jimmy Carter, who created the Department of Energy in 1977.^[2]
The Energy Information Administration projected that by 2017, biomass is expected to be about twice as expensive as natural gas, slightly more expensive than nuclear power, and much less expensive than solar panels.^[7] In another EIA study released, concerning the government’s plan to implement a 25% renewable energy standard by 2025, the agency assumed that 598 million tons of biomass would be available, accounting for 12% of the renewable energy in the plan.^{[8]
Source: wikipedia}