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The magical world of BIOENERGY Social and political implications as well as some science. Emily J. May Energy Alternatives February 28, 2007. What is Bioenergy?. Bioenergy is: - PowerPoint PPT Presentation
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The magical world of BIOENERGYSocial and political implications as well as some science
Emily J. May
Energy Alternatives
February 28, 2007
What is Bioenergy?
Bioenergy is:“energy derived from recently living material such as wood, crops, or animal waste.” (versus decayed materials that comprise fossil fuels)
Can be burned directly for heat or converted to biofuels such as biodiesel or ethanol.
Currently approx 1 million Mtoe, projected to double in 25 years 1% of cumulative investment
Come On Baby Light My Fire:A Brief History of Biofuels
Humans have derived energy from organic matter for millennia. wood and animal dung Grass fuel for animals as agriculture and
domestication began. Animal fat candles- Industrial Revolution
Traditional Biomass
Burning of wood, animal dung and plant matter
Common in developing countries as a primary energy source
Provides 48 EJ to world primary energy (approximate figure)
The Path to Prosperity?
“Haiti might be able to supply the Dominican Republic with biofuels while strengthening its own economy and mitigating the increased greenhouse gases that can accompany economic development. [Haiti] has a large agrarian citizenship, a eastern neighbor eager for biofuels, and a consistent mandate from the international community to increase standard-of-living. Haiti…may be able to strengthen its ravaged economy by helping a neighbor decrease its use of fossil fuels - which can only be good for an island poised to suffer from the adverse effects of climate change.”
http://www.haitiinnovation.org/node/308?gclid=CI6TqJq0zYoCFSZfQAodyW-UdA
“New” Biomass
Produced on a large commercial scale in industrialized nations- 7% primary energy
Provides 9 EJ (2%) of world primary energy
Energy Crops: Plants that are grown specifically for use as biofuels
Organic Wastes: byproduct of direct uses of biomass, eg. agriculture.
Energy Crops
Woody crops: trees harvested for biofuel Europe, U.S. and Australia
Agricultural crops most common are sugar cane and maize for
conversion into liquid fuels Plants such as sunflowers and soybeans are
grown for the oil in their seeds’ conversion to biodiesel
ETHANOL
U.S. 101 plants- 4.8 billion gallons/year 2005- 4 billion gallons used = 1.2 fewer cars (?)
Brazil PRO-ALCOOL is the world’s biggest biomass
system. Vehicles run on “gasohol” (26% ethanol) Developed during economic hardship, saved
over $40 billion
Organic Wastes
Wood Residues: byproduct of plantation thinning
Temperate Crop Wastes: unused portion of wheat, maize and corn crops; over a billion tonnes/year. 15-20 EJ
Tropical Crop Wastes: sugar and rice, 18 EJ.
Animal Wastes: anaerobic digestion of manure can be converted to fuel
Organic Waste Cont.
Municipal Solid Waste Landfill Gas
anaerobic digestion of biological material produces landfill gas which has been used since the 1970s. Has low efficiency.
Commercial and Industrial waste
How Does It All Work?
Solid biomass Combustion produces heat energy and CO2.
Gaseous fuels Anaerobic digestion: disgester enables bacteria
to break down matter, creating heat. Gasifier: hot steam and oxygen + volatiles and
char= producer gas
How Does It All Work? Cont.
Liquid Fuels Pyrolysis: heating bio material to extract volatile
components, then condensed, made into bio-oil. Approx. half the energy of crude oil
Synthesis: gasification produces syngas (CO and H2), condensed into liquid.
Fermentation: sugars converted to alcohol by organisms such as yeast.
Bioenergy in the US
Cheap petroleum has consistently destroyed US bioenergy market
second to Windpower in renewables3% of US energy consumptionethanol and biodiesel currently in useFuture: biomass to produce plastics and
chemicals
US Biofuel Prices
Biodiesel:.50/litreEthanol
maize: .23/litre wood: .62/litre
Crude oil, Feb 2007: .60/litre
Focus of the US DOE Biomass Program: An Impressively Convoluted Diagram (no questions please)
Bioenergy in Burlington
The McNeil Biomass Plant conventional wood-burning plant that has been
in operation since 1984 Uses biogasification: converts organic fuels into
“clean” gas McNeil uses 200 tons of locally produced wood
per day!
But is it sustainable?
70% from low quality trees and forest residue
25% is byproduct of local sawmills
5% recycled urban wood waste
Burlington’s McNeil Biomass Plant
catalytic system cleans gas, compress gas, sends through turbine
Emissions are 1/100 of the permitted federal level
50 MW capacity:
1/10 size of Vermont Yankee but still enough power for all of Burlington
Bioenergy in Belize
2002 Johannesburg World Summit Central American Commission on Environment
and Development Feasibility of bioenergy in Belize by NGOs
GBEP (2006): bioenergy to developing nations
Belize has no Clean Development Mechanism (Kyoto Protocol)
No large-scale bioenergy production
Freedom from Fossil Fuels!
Biofuels “should generate no more heat and create no more carbon dioxide than would have been formed in any case by natural processes.” (106)
BUT WAIT! What about those conversion efficiencies?
The low conversion efficiency of biomass to bioenergy is almost as hard to justify as a war for oil
“air-dry mass of plant matter produced annually on an area of one hectare can be as little as one tonne.” (112)
This produces only 15 GJ/hectare/year!
Burning Bush
“Twenty by Ten” introduced in the 2007 State of the Union address proposes a decrease of fossil fuel use in 10 years by replacing 15% with biofuels and increased fuel efficiency of cars by 5%
Biofuel production must increase fivefold Seeks $3.6 billion for the research and
development of new fuels using "everything from wood chips, to grasses, to agricultural wastes"
“Addicted to Biofuels”?
When demand for biofuels exceeds a sustainable production rate, bioenergy is no longer a viable energy source.
high level of energy and resource input "All the fossil fuels that are used in the
production of corn, in the fertilizers and in the fuel, in the ploughs and transportation and so on and in the distillation process, it becomes almost a very dirty fuel.” –Kurt Davies, Greenpeace USA
Sources cited
Bioenergy: US Department of Energy. http://www.energy.gov/energysources/bioenergy.htm
“Q&A: Bush’s Energy Reforms” 24 Jan, 2007. http://news.bbc.co.uk/2/hi/americas/6293805.stm
“US Ethanol Production.” http://www.ksgrains.com/ethanol/useth.html
Boyle, Godfrey. Renewable Energy: Power For a Sustainable Future. Oxford Press 2004, Glasgow.
Lallement, Dominque. “The Role and Significance of Latin America in Global Energy Markets.”Amsterdam, 19 Dec. 2006.
Nurmi, Dr. Marrku. Central American Carbon Finance Guide. September 2004.http://www.greenstream.net/content/Projects/carbono_en.pdf?from=204215008731975
Riley, Kate M. 27 Feb, 2007.
Valenti, Michael. “Preaching to the converted.” Mechanical Engineering, 2001. http://www.memagazine.org/backissues/membersonly/dec01/features/preaching/preaching.html
Questions? Consult your book.