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    As part of its 'Le dessous des cartes' magazine, Europe's culture TV channel ARTE airs a documentary about the geopolitics of sustainable transport tonight, at 10.20 pm CET. Readers outside of Europe can catch it here. ARTE - April 18, 2007.

    Spain's diversified company the Ferry Group is investing €50 million into a biomass plantation in new EU-memberstate Bulgaria. The project will see the establishment of a 8000ha plantation of hybrid paulownia trees that will be used for the production of fuel pellets. Dnevnik, Bulgaria - April 18, 2007.

    Bioprocess Control signs agreement with Svensk Biogas and forms closer ties with Swedish Biogas International. Bioprocess Control develops high-tech applications that optimise the commercial production of biogas. It won Sweden's prestigious national clean-tech innovations competition MiljöInnovation 2007 for its 'Biogas Optimizer' that accelerates the biogas production process and ensures greater process stability. NewsDesk Sweden - April 17, 2007.

    A joint Bioenergy project of Purdue University and Archer Daniels Midland Company has been selected to receive funding by the U.S. Department of Energy to further the commercialization of highly-efficient yeast which converts cellulosic materials into ethanol through fermentation. ADM - April 17, 2007.

    Researchers at Iowa State University and the US Department of Agriculture's Agricultural Research Services (ARS) have found that glycerin, a biodiesel by-product, is as effective as conventional corn-soymeal diets for pigs. AllAboutFeed - April 16, 2007.

    U.S. demand for uranium may surge by a third amid a revival in atomic power projects, increasing concern that imports will increase and that limited supplies may push prices higher, the Nuclear Energy Institute says. Prices touched all time highs of US$113 a pound in an auction last week by a U.S producer amid plans by China and India to expand their nuclear power capacity. International Herald Tribune - April 16, 2007.

    Taiwan mandates a 1% biodiesel and ethanol blend for all diesel and gasoline sold in the country, to become effective next year. By 2010, the ratio will be increased to 2%. WisconsinAg Connection - April 16, 2007.

    Vietnam has won the prestigious EU-sponsored Energy Globe award for 2006 for a community biogas program, the Ministry of Agriculture and Rural Development announced. ThanhNien News - April 13, 2007.

    Given unstable fossil fuel prices and their negative effects on the economy, Tanzania envisages large-scale agriculture of energy crops Deputy Minister for Agriculture, Food Security and Cooperatives, Mr Christopher Chiza has said. A 600 hectare jatropha seed production effort is underway, with the seeds expected to be distributed to farmers during the 2009/2010 growing season. Daily News (Dar es Salaam) - April 12, 2007.

    Renault has announced it will launch a flex-fuel version of its Logan in Brazil in July. Brazilian autosales rose 28% to 1,834,581 in 2006 from 2004. GreenCarCongress - April 12, 2007.

    Chevron and Weyerhouser, one of the largest forest products companies, are joining forces to research next generation biofuels. The companies will focus on developing technology that can transform wood fiber and other nonfood sources of cellulose into economical, clean-burning biofuels for cars and trucks. PRNewswire - April 12, 2007.

    BioConversion Blog's C. Scott Miller discusses the publication of 'The BioTown Source Book', which offers a very accessible introduction to the many different bioconversion technologies currently driving the bioenergy sector. BioConversion Blog - April 11, 2007.

    China's State Forestry Administration (SFA) and the China National Cereals, Oils and Foodstuffs Import & Export Corp., Ltd. (COFCO) have signed a framework agreement over plans to cooperatively develop forest bioenergy resources, COFCO announced on its web site. Interfax China - April 11, 2007.

    The Ministry of Agriculture and Livestock of El Salvador is speeding up writing the country's biofuels law in order to take advantage of the US-Brazil cooperation agreement which identified the country as one where projects can be launched fairly quickly. The bill is expected to be presented to parliament in the coming weeks. El Porvenir - April 11, 2007.

    ConocoPhillips will establish an eight-year, $22.5 million research program at Iowa State University dedicated to developing technologies that produce biofuels. The grant is part of ConocoPhillips' plan to create joint research programs with major universities to produce viable solutions to diversify America's energy sources. Iowa State University - April 11, 2007.

    Interstate Power and Light has decided to utilize super-critical pulverized coal boiler technology at its large (600MW) new generation facility planned for Marshalltown, Iowa. The plant is designed to co-fire biomass and has a cogeneration component. The investment tops US$1billion. PRNewswire - April 10, 2007.

    One of India's largest sugar companies, the Birla group will invest 8 billion rupees (US$187 million) to expand sugar and biofuel ethanol output and produce renewable electricity from bagasse, to generate more revenue streams from its sugar business. Reuters India - April 9, 2007.

    An Iranian firm, Mashal Khazar Darya, is to build a cellulosic ethanol plant that will utilise switchgrass as its feedstock at a site it owns in Bosnia-Herzegovina. The investment is estimated to be worth €112/US$150 million. The plant's capacity will be 378 million liters (100 million gallons), supplied by switchgrass grown on 4400 hectares of land. PressTv (Iran) - April 9, 2007.

    The Africa Power & Electricity Congress and Exhibition, to take place from 16 - 20 April 2007, in the Sandton Convention Centre, Johannesburg, South Africa, will focus on bioenergy and biofuels. The Statesman - April 7, 2007.

    Petrobras and Petroecuador have signed a joint performance MOU for a technical, economic and legal viability study to develop joint projects in biofuel production and distribution in Ecuador. The project includes possible joint Petroecuador and Petrobras investments, in addition to qualifying the Ecuadorian staff that is directly involved in biofuel-related activities with the exchange of professionals and technical training. PetroBras - April 5, 2007.

    The Société de Transport de Montréal is to buy 8 biodiesel-electric hybrid buses that will use 20% less fuel and cut 330 tons of GHG emissions per annum. Courrier Ahuntsic - April 3, 2007.

    Thailand mandates B2, a mixture of 2% biodiesel and 98% diesel. According to Energy Minister Piyasvasti Amranand, the mandate comes into effect by April next year. Bangkok Post - April 3, 2007.

    In what is described as a defeat for the Bush administration, the U.S. Supreme Court ruled [*.pdf] today that environmental officials have the power to regulate greenhouse gas emissions that spur global warming. By a 5-4 vote, the nation's highest court told the U.S. Environmental Protection Agency to reconsider its refusal to regulate carbon dioxide and other emissions from new cars and trucks that contribute to climate change. Reuters - April 2, 2007.

    Goldman Sachs estimates that, in the absence of current trade barriers, Latin America could supply all the ethanol required in the US and Europe at a cost of $45 per barrel – just over half the cost of US-made ethanol. EuroToday - April 2, 2007.

    The Kauai Island Utility Cooperative signed a long-term purchase power agreement last week with Green Energy Team, LLC. The 20-year agreement enables KIUC to purchase power from Green Energy's proposed 6.4 megawatt biomass-to-energy facility, which will use agricultural waste to generate power. Honolulu Advertiser - April 2, 2007.

    The market trend to heavier, more powerful hybrids is eroding the fuel consumption advantage of hybrid technology, according to a study done by researchers at the University of British Columbia. GreenCarCongress - March 30, 2007.

    Hungarian privately-owned bio-ethanol project firm Mabio is planning to complete an €80-85 million ethanol plant in Southeast Hungary's Csabacsud by end-2008. Onet/Interfax - March 29, 2007.

    Energy and engineering group Abengoa announces it has applied for planning permission to build a bioethanol plant in north-east England with a capacity of about 400,000 tonnes a year. Reuters - March 29, 2007.

    The second European Summer School on Renewable Motor Fuels will be held in Warsaw, Poland, from 29 to 31 August 2007. The goal of the event is to disseminate the knowledge generated within the EU-funded RENEW (Renewable Fuels for Advanced Powertrains) project and present it to the European academic audience and stakeholders. Topics on the agenda include generation of synthetic gas from biomass and gas cleaning; transport fuel synthesis from synthetic gas; biofuel use in different motors; biomass potentials, supply and logistics, and technology, cost and life-cycle assessment of BtL pathways. Cordis News - March 27, 2007.

    Green Swedes want even more renewables, according to a study from Gothenburg University. Support for hydroelectricity and biofuels has increased, whereas three-quarters of people want Sweden to concentrate more on wind and solar too. Swedes still back the nuclear phase-out plans. The country is Europe's largest ethanol user. It imports 75% of the biofuel from Brazil. Sveriges Radio International - March 27, 2007.

    Fiat will launch its Brazilian-built flex-fuel Uno in South Africa later this year. The flex-fuel Uno, which can run on gasoline, ethanol or any combination of the two fuels, was displayed at the Durban Auto Show, and is set to become popular as South Africa enters the ethanol era. Automotive World - March 27, 2007.

    Siemens Power Generation (PG) is to supply two steam turbine gensets to a biomass-fired plant in Três Lagoas, 600 kilometers northwest of São Paulo. The order, valued at €22 million, was placed by the Brazilian company Pöyry Empreendimentos, part of VCP (Votorantim Celulose e Papel), one of the biggest cellulose producers in the Americas. PRDomain - March 25, 2007.

    Asia’s demand for oil will nearly double over the next 25 years and will account for 85% of the increased demand in 2007, Organization of Petroleum Exporting Countries (Opec) officials forecast yesterday at a Bangkok-hosted energy conference. Daily Times - March 24, 2007.

    Portugal's government expects total investment in biomass energy will reach €500 million in 2012, when its target of 250MW capacity is reached. By that date, biomass will reduce 700,000 tonnes of carbon emissions. By 2010, biomass will represent 5% of the country's energy production. Forbes - March 22, 2007.

    The Scottish Executive has announced a biomass action plan for Scotland, through which dozens of green energy projects across the region are set to benefit from an additional £3 million of funding. The plan includes greater use of the forestry and agriculture sectors, together with grant support to encourage greater use of biomass products. Energy Business Review Online - March 21, 2007.

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Wednesday, April 18, 2007

First comprehensive energy balance study reveals cassava is a highly efficient biofuel feedstock

While most of the world is scrambling after corn and sugar for answers to its renewable energy needs, many developing countries are focusing on a lesser known plant — cassava, also known as manioc. A new study for the first time calculates the net energy value ('NEV', 'energy balance') of cassava ethanol and finds that the tropical starchy tuber makes for a highly efficient source of renewable energy.

Cassava, a crop grown across the Global South, is a hardy plant that thrives in relatively poor soils and requires limited water and fertiliser inputs. It grows explicitly on land not associated with rainforests (see map, click to enlarge), and several hundred million hectares of unused non-forest land suitable for cassava are available in the tropics and the sub-tropics. Some of the world's leading biotech scientists, including two Nobel Laureates, Norman Borlaug (father of the Green Revolution) and S. Mohan Jain, are working on improving cassava as an energy crop.

Global land suitability for rainfed cassava (click to enlarge)
Studying the energy balance of biofuels is important because if they do not yield much net energy, the question is whether the resources they use up (land, water) can be used in a better way. There is some controversy surrounding the energy balance of ethanol made from corn, with some scientists finding that the fuel has a negative balance; in other words, more energy is invested in the production chain than is contained in the finished fuel product. Other researchers have found a slightly positive balance of around 1.5 - for each unit of energy invested in the production of corn ethanol, 1.5 units of energy are contained in the fuel once you pour it into the tank of a vehicle (earlier post). For sugarcane based ethanol, the energy balance is between 8 and 10 (earlier post).

Tropical crops have a significant advantage over biofuel crops grown in temperate climates: they convert sunlight more efficiently into biomass and yield far more of it. The result: the energy balance of biofuels made from such crops is considerably stronger. Or in other words, to produce one unit of energy in the form of a liquid fuel, tropical crops require far less land and resources than crops grown in temperate regions.

Thu Lan Thi Nguyen, Shabbir H. Gheewala, and Savitri Garivait from the Thonburi University of Technology have now determined that the same logic holds for cassava (Manihot esculenta), grown in a tropical country like Thailand. They published their findings in the journal Environmental Science & Technology. The results provide a "framework" for policy makers to evaluate whether ethanol from cassava is feasible and practical, says lead author Shabbir Gheewala.

Net renewable energy balance
Thailand already has a cassava-derived ethanol pilot plant, and the government is aiming to build 12 full-scale facilities by 2008, based on expanded cassava plantings that are set to benefit small farmers (earlier post). Using scaled-up data from this existing pilot plant, the authors calculate the NEV of cassava-based ethanol as 10.22 megajoules per liter (MJ/L), an overall positive yield. The most optimistic assessment for corn shows an NEV of around 4.51 MJ/L, meaning cassava is more than two times as efficient. NEV is a measure of the energy content of ethanol minus the net energy used in the production process. The usefulness of NEV in evaluating an ethanol source is debatable, but with well-defined boundaries and clearly stated assumptions, it can provide a measure of the energy consumption and yield of the ethanol production from a one particular source.

NEV may not be the best instrument to evaluate biofuels' contribution to energy security, the authors point out in the paper. 'Renewability' is equally important. This factor is determined by the amount of fossil fuels used in the ethanol-manufacturing process. Consequently, they used yet another tool, the "net renewable energy value", defined as the energy content of ethanol minus the total fossil-energy inputs. When fossil-fuel inputs (97.35% of the energy inputs) were taken into consideration, the NREV of cassava fell to 9.15 MJ/L - still strongly positive.

According to the authors, several features make cassava more advantageous than sugar cane or cane molasses:
:: :: :: :: :: :: :: :: ::

The tuber is already used as a starch source and for chip/pellet products. It can be grown in any season and can be a year-round source of ethanol. "In Thailand, cassava is the third most important cash crop after rice and sugar cane," says Gheewala. Sugarcane is a seasonal crop, and since ethanol cannot be stored during long periods of time, bridging the period between cane harvesting and the off-season is problematic.

"Over the past 20 to 30 years, cassava agronomy research has contributed significantly to the development of improved agricultural practices, such as time and method of planting, intercropping, soil erosion control, and especially, weed control and fertilizing." The result: Thailand uses less fertilizers and herbicides than China to grow cassava, yet it provides a comparable yield.

Importance for policy makers
The study "addresses a question that's of policy interest right now," says agricultural economist Satish Joshi of Michigan State University. Uwe Fritsch at the Institute for Applied Ecology (Germany) agrees. "Cassava is a feedstock that is not in the major debate so far," and yet it is a crop of "relevance for a lot of developing countries," he says. The findings also explain the "life-cycle implications of this kind of biofuel," he adds.

However, the authors' calculations will remain meaningless without an understanding of their economic relevance, says Fritsch. "We have a lot of solar energy, for example, but it's very expensive so it does not mean much." The authors agree. "A general idea about the market dynamics is useful to understand the overall situation," they report in the paper.

Fritsch also points out the absence of any reference to greenhouse-gas emissions. "Net energy balance is for scientists," he says. The real economic implications of any biofuel source remain unknown without an estimate of its greenhouse-gas emissions, because that is where "most of the current debate" lies, Fritch adds. For many biofuels made from different crops, such GHG-emissions balances have been carried out. For corn ethanol, for example, some researchers have found that it does not reduce GHG-emissions very much (earlier post); sugarcane ethanol does so far better (earlier post). For other tropical crops, this aspect still needs to be investigated.

Cassava biotech research
Some of the world's leading scientists are working on improving cassava. Amongst them Norman Borlaugh, father of the Green Revolution, who is sequencing the crop's genome in order to breed varieties for energy. His work is part of the bioenergy research at the U.S. Department of Energy's Joint Genome Institute (earlier post).

Earlier, we also pointed to research being undertaken by researchers from the International Atomic Energy Agency, who are using the latest plant breeding techniques to make cassava an even more interesting energy crop. The tools: nuclear techniques to induce mutagenesis and obtain mutant varieties, and space-breeding, which is based on a similar process but then relying on radiation from space that affects and transforms seeds into interesting varieties.

More information:

Thu Lan Thi Nguyen, Shabbir H. Gheewala, and Savitri Garivait, "Full Chain Energy Analysis of Fuel Ethanol from Cassava in Thailand" [*abstract], Environ. Sci. Technol.; 2007; ASAP Web Release Date: 11-Apr-2007; and article: DOI: 10.1021/es0620641


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