Biomass
Biomass is a renewable energy source because the energy it contains comes from the sun. Plant or animal-based materials such as crops, crop residues, trees, animal fats, by-products, and organic wastes are all considered biomass. These materials are often obtained from agriculture and forests, but can also be derived from industrial and municipal sources such as wastewater treatment plants.
Through the process of photosynthesis, chlorophyll in plants captures the sun’s energy by converting carbon dioxide from the air and water from the ground into carbohydrates, complex compounds composed of carbon, hydrogen, and oxygen. When these carbohydrates are burned, they turn back into carbon dioxide and water and release the sun’s energy they contain. In this way, biomass functions as a sort of natural battery for storing solar energy and recycling carbon dioxide. As long as biomass is produced sustainably—with only as much used as is grown—the battery will last indefinitely. Biomass supplies almost 15 times as much energy in the United States as wind and solar power combined—and has the potential to supply much more.
What is Bioenergy?
Bioenergy refers to sources of energy (electricity and solid, liquid, or gaseous fuels) derived from biomass. Biomass solids can be burned alone or with fossil fuels to generate direct heat, steam, and/or electrical energy.
Some Examples:
Florida Crystals, a sugar producing company in South Florida provides an example of biomass to electrical energy. Since 1995, the company has been burning left over sugar cane residue known as bagasse, to produce electricity for their operations and about 60,000 homes. The bagasse is supplemented with local wood waste. This biomass plant is the largest in the country.
Biomass Gas & Electric, a 21st century company, has contracts with Progress Energy and the City of Tallahassee to build state-of-the-art biomass electric plants.
In May, 2009, the City of Sanford opened a wastewater sludge gasification system. The system converts sludge to syngas to displace natural gas for the city’s sludge dryer.
Biofuel
Biofuel is bioenergy converted into a liquid fuel such as ethanol or biodiesel, but biomass can also be converted into gaseous fuels via biological or chemical processes such as digestion and gasification. The 2007 Energy and Security Act aims to increase biofuel production from 9 billion gallons per year (BGY) in 2008 to 36 BGY by 2022.
Biodiesel
Biodiesel is a renewable fuel produced from plant oils, animal fats, used cooking oil and even new sources such as algae. Biodiesel contains no petroleum, but it can be blended at any level with petroleum diesel and requires little or no engine modifications. Fuel grade biodiesel must meet the industry standard (ASTM D6751) for legal sale and distribution. Biodiesel is not the same as ethanol and must not be used in gasoline engines.
Ethanol
Most of the ethyl alcohol, or ethanol, used in vehicle fuel is produced by fermentation of a sugar solution. In the United States, most ethanol is currently derived from the starches in corn kernels; other types of plant material such as grasses, wood, and agricultural wastes can be used to make “cellulosic”ethanol (named for the long chains of sugars that are the main component of plant cell walls), but this process is more complex. Researchers are working to make cellulosic ethanol production more efficient and affordable. The Energy and Security Act requires that fifty percent of ethanol production be from cellulosic sources by 2020 and the ratio increases in subsequent years.
Biobutanol
Biobutanol is another liquid alcohol fuel made from the same sources as ethanol. Researchers say it has greater energy content than ethanol.
Biofuel Retailers
The National Biodiesel Board lists biodiesel retailers in Florida at:
http://www.biodiesel.org/buyingbiodiesel/retailfuelingsites/biomaps/biomaps.shtm
The Renewable Fuels Association now lists E-85 (85 % ethanol and 15 % gasoline used in flex-fuel vehicles) retailers in Florida at www.ethanolrfa.org
Ethanol and biodiesel production plants are starting up in Florida quite rapidly. Keep informed about their progress and other Renewable Energy projects by subscribing to the FREA Solar State News.
Sources:
USEPA http://www.epa.gov/sustainability/energy.htm
Union of Concerned Scientists:
http://www.ucsusa.org/clean_energy/technology_and_impacts/energy_technologies
Florida Crystals http://www.floridacrystals.com/content/112/renewable_energy.aspx
Biomass Gas & Electric http://www.biggreenenergy.com/Default.aspx?tabid=2875
MaxWest Sludge Gasification System at Sanford http://maxwestenergy.com/downloads/tour_graphic.pdf
