<body> --------------
Contact Us       Consulting       Projects       Our Goals       About Us
home / Archive
Nature Blog Network

    Taiwan's Feng Chia University has succeeded in boosting the production of hydrogen from biomass to 15 liters per hour, one of the world's highest biohydrogen production rates, a researcher at the university said Friday. The research team managed to produce hydrogen and carbon dioxide (which can be captured and stored) from the fermentation of different strains of anaerobes in a sugar cane-based liquefied mixture. The highest yield was obtained by the Clostridium bacterium. Taiwan News - November 14, 2008.

Creative Commons License

Friday, November 14, 2008

Bioenergy projects win big environment, energy and development awards

Poor people in developing countries have very few options for gaining access to modern energy services, most notably electricity. Renewables like solar, wind and hydropower are way too expensive, intermittent and require outside expertise, whereas fossil fuel based power plants are non-renewable and often centralised to pass ruralites by. That leaves smart bioenergy systems. No wonder then that biomass power projects are winning some of the world's most coveted awards dealing with bringing clean energy to poor people in developing countries. Bioenergy reigned supreme at this year's Tech Awards, which saw 329 outstanding candidates and hundreds of nominations representing 68 countries. Each winner received $50,000.

Saving species and ecosystems with bioenergy

The winner of the 2008 Intel Environment Award is the Cheetah Conservation Fund in Namibia, which turns an invasive plant into a clean biomass fuel.

This biomass power project saves land and protects the cheetahs. It employs 15 people at a biomass processing plant that uses a high-pressure extrusion process to create an economically viable alternative to firewood, coal, and charcoal. The fund is working to recover 25 million acres of land in Namibia and to save endangered cheetahs.

We reported earlier on the large biomass resource in Namibia, consisting of invasive thorn acacia species which ruin local biodiversity and make agriculture impossible. This major environmental problem costs hundreds of millions a year to the country, and eradicating it would add billions. Turning the resource into bioenergy is now emerging as the smartest solution. Doing so not only solves an energy crisis, it also protects the environment, reduces emissions, and conserves land that is home to unique species, like the magnificent cheetah.

The Cheetah Conservation Fund's bioenergy project was lauded for its efforts to remove the thorn bushes from the savannas to help reverse an ecological disaster and replenish Namibia's vanishing ecosystems.

Power to the people: breaking poverty with bioenergy

Another smart bioenergy concept has been developed by Decentralised Energy Systems India (DESI), which won the prestigious 2008 Accenture Economic Development Award. DESI Power is helping more than 100 villages build small-scale power plants to areas that lack electricity and is creating jobs with the launch of micro-enterprises.

The DESI plants use biomass gasification to provide power that costs up to 20 times less than realistic alternatives like solar power. None of the poor villagers could ever afford solar energy, but the bio-electricity is within their reach. To electrify the villages, DESI's biomass gasification plants use the abundant agricultural waste streams generated by the farmers themselves. Waste products from the conversion are returned to the soil.

What's more, the projects are registered by the UNCCD as Clean Development Mechanism projects, which means they receive carbon credits. This money helps end poverty in the villages.

When electricity arrives, poor villages are entirely transformed. DESI's "magic" allows for the sudden revitalisation of rural communities: farmers succeed in pumping and selling irrigation water, small entrepreneurs make a business out of charging batteries for cell phones, making ice or creating village cinemas. Women get a break with electric mills making the backbreaking work of crushing farm products a thing of the past. More important services, like storing medicines in fridges or lighting up schools are made possible as well.

Winners in other categories were Build Change (Equality Award), a San Francisco-based nonprofit that designs and trains builders and homeowners how to build earthquake-resistant houses in developing countries, and Star Syringe (Innovation Health Award), which developed a syringe that reduces the spread of disease because it can only be used once [entry ends here].
:: :: :: :: :: :: :: :: :: ::

Article continues

France approves injection of biomethane into natural gas network

The EU's BiogasMax project reports that, in France, authorisation for injecting biomethane fuel into the natural gas distribution network has been the subject of an environmental and health risk assessment. The French Agency for Health and Safety in the Environment and Workplace (AFSSET) came to a favourable conclusion on the 29th October and has given the go-ahead for feeding the renewable gas into the French natural gas network. This means NGV cars will soon be driving on renewable gas. The injection of biomethane into gas pipelines, as well as a fiscal approach which favours green gas production, will allow the biomethane sector - considered the best pathway to valorize biogas - to make progress under much better conditions.

Although natural gas as a fuel is already considered to be safe, efficient and less polluting than petrol or diesel, French support for the field of biomethane fuel is fairly recent. However, initiatives have demonstrated many benefits of the upgraded biogas. In Lille (Metropolitan Urban Community, LMCU), the methanisation of urban organic waste has meant that the biomethane obtained has been used as a fuel in the city’s buses and domestic waste disposal vehicles. Furthermore, this approach has been legitimised environmentally by a study of the life cycle of biogas production pathways [*.pdf], commissioned in September 2007 by ADEME and GDF.

At the ‘Grenelle Environnement' held in October 2007 - France's large national summit on the future of the environment - the biogas club had submitted several ways of proceeding with the work for developing this field, which it says has "enormous ecological benefits". The club’s voice was heard: at a recent conference on this subject, Charles Thiébaut (from the Department of Risk Prevention at the Ministry of the Environment, Energy, Sustainable Development and Town and Country Planning) said that "the commitment had been made to favour methanisation by supporting it and modifying regulations" (National Technical Day conference, 07.10.08 – Succeeding with a methanisation project including household, agricultural and industrial waste, ADEME).

The city of Lille, France, runs 100 buses on biomethane, as part of the EU's BiogasMax project.
However, the development of the biogas fuel sector had to await the authorisation to inject its biomethane into the natural gas network, as even if the production of biogas is continuous, vehicle consumption can fluctuate. In order to be used as a fuel, biogas has to undergo processes known as 'purification' (drying, desulphurisation, decarbonisation) which makes biomethane very similar to NGV, natural gas for vehicles:
:: :: :: :: :: :: :: :: ::

In the first instance, therefore, authorisation for injection had to be subject to technical specifications. These having been established and published by GDF in December 2007 (see the GDF technical specifications[*.pdf]), there only remained the assessment of risks to public health and the environment. This risk assessment analysis was requested from the French Agency for Health and Safety in the Environment and Workplace (AFSSET) in September 2006. Its conclusions are now available and are "unequivocally favourable when biogas is produced from methanisation of waste or from storage of non-dangerous waste."

Very soon, therefore, the Centre for Organic Development (CVO) in Lille-Sequedin will receive authorisation from the Ministry in charge of energy and be able to put into operation the connection of its canalisation system of purified biogas with the French gas network. Having opened the way, it will be the local authorities who will subsequently issue further authorisations.

According to BiogasMax, administrative support is certainly necessary, but fiscal support would also be very beneficial, in the sense that economic profitability is absolutely necessary in order to develop the sector. At the ‘Grenelle Environnement' this topic was tackled, because it represents a question of "bringing support for the use of biogas as a fuel up to the same level as the production of electricity", (speech by Mr Thiébaut at the conference on 07.10.08).

It is noteworthy that in the Finance Law of 2008, NGV was exempted from the TIPP (tax on consumption of petrol products). If one accepts that biomethane fuel is identical to NGV but is also renewable, it should also be able to benefit from this fiscal rule. Putting forward the principle of 'green gas', following the example of 'green electricity' would prove to be a very strong factor for development of the sector. Moreover in Sweden, which is very advanced in the development of this field, the Swedish fiscal authority will begin examining support for biomethane from 2009 onwards.

France is the latest in a series of European countries to allow biomethane to be fed into the natural gas grid. Earlier, Austria, Switzerland and Germany undertook similar measures. According to some assessments, biogas can replace all the EU's natural gas imports from Russia, by 2030 (previous post). The U.S. too has recently begun investigating the option of opening the gas grid for biomethane (more here).

BiogasMax: Biomethane coming to the French natural gas network - November 2008.

The EU's BiogasMax project.

AFSSET: Biogaz : L'Afsset rend un avis favorable pour l'injection de certains types de biogaz dans le réseau de gaz naturel - October 29, 2008.

ADEME, GDF: Analyse du Cycle de Vie des modes de valorisation du biogaz de méthanisation en France Synthèse [*.pdf] - September 2007

GDF: Prescriptions techniques du distributeur Gaz de France prises en application du décret n° 2004-555 du 15 juin 2004 relatif aux prescriptions techniques applicables aux canalisations et raccordements des installations de transport, de distribution et de stockage de gaz [*.pdf] - December 2007.

Biopact: Report: biogas can replace all EU natural gas imports - January 04, 2008

Biopact: Germany considers opening natural gas network to biogas - major boost to sector - August 11, 2007

Biopact: E.ON creates company to feed biogas into the natural gas grid - February 10, 2007

Biopact: A first for the U.S.: company feeds biomethane into natural gas pipeline - January 22, 2008

Biopact: EU research project looks at feeding biogas into the main natural gas grid - April 08, 2007

Article continues

Thursday, November 13, 2008

GSI report: China's biofuel subsidies need rethink

A new report finds that China provided a total of RMB 780 million (€91/US$ 115 million, roughly €0.32/US$ 0.40 per litre) in biofuel subsidies in 2006. Total support is expected to reach approximately RMB 8 billion (€940 million/US$ 1.2 billion) by 2020, according to official sources (table, click to enlarge). This is likely to be a significant underestimate, as it does not include support to feedstocks, such as the RMB 3000 (€352/US$ 437) per hectare per year available from 2007 for farmers growing feedstock on marginal land.

Subsidies provided at different points in the biofuel supply chain
Biofuels – At What Cost? Government support for ethanol and biodiesel in China [*.pdf], is the latest in a series of country studies on subsidies for biofuels by the Global Subsidies Initiative (GSI), a Geneva-based programme of the International Institute for Sustainable Development (IISD). (See previous posts on the GSI's reports on biofuel subsidies in the US, and EU support measures).

A domestic biofuels industry seemed an attractive option to Beijing as a means of improving energy supply for China’s soaring transport needs, reducing air pollution and building a “new socialist countryside” by creating alternative markets for grain and opportunities in China’s poor rural areas.

However, the government quickly recognised the inherent conflict between first generation biofuels and food production. It is now in the awkward position of seeking to discourage the use of staple crops for biofuels production, yet at the same time paying production subsidies predominantly to ethanol producers using maize and wheat as feedstocks. The construction of new maize-based ethanol plants has been halted. Policies have been developed to encourage the production of biofuels from non-grain feedstocks instead, grown on 35 to 75 million hectares of marginal land that might be suitable for these crops.

According to the report, the impacts of converting “marginal lands” to feedstock production will depend on local circumstances. Benefits could include higher farm incomes and rehabilitation of degraded land. However, in some areas yields might be too low to make growing of feedstock profitable, and government subsidies would be wasted on such land. Negative impacts could also arise if existing land users are displaced or natural ecosystems are disrupted. Subsidies for growing biofuel feedstocks on marginal land are higher than subsidies for setting aside such land for environmental purposes, encouraging cultivation of conservation areas:
:: :: :: :: :: :: :: :: :: ::

Even under the most optimistic scenarios for Chinese biofuel production, soaring private vehicle ownership means domestic production of biofuels would have a negligible effect in reducing China’s oil consumption or increasing energy security. The net benefits for pollution reduction also appear to be limited and the potential for negative unintended consequences is high, including for vulnerable rural communities. The report therefore recommends that the Chinese Government re-evaluates its biofuel policies, particularly to ensure that biofuels genuinely do not compete with food or undermine the government’s social or environmental objectives.

More generally, China should hasten the liberalization of transport fuel prices. China’s current price caps undermine the government’s energy-efficiency goals. If improving energy security and reducing urban pollution are genuine priorities, then allowing domestic fuel prices to rise to those established in international markets would be the most effective step that China could take to curb demand, particularly if such action is accompanied by policies to improve vehicle efficiency and slow growth in car ownership.


Global Subsidies Initiative: "Biofuels – At What Cost? Government support for ethanol and biodiesel in China" - November 2009.

Biopact: Subsidies for uncompetitive U.S. biofuels cost taxpayers billions - report - October 26, 2006

Biopact: IISD report challenges EU biofuel subsidies, calls for end to tariff - October 04, 2007

Article continues

Wednesday, November 12, 2008

Renewables hit by financial crisis: banks pull out of offshore wind company C-Power

The green energy sector is being hit by the financial crisis in a dramatic way. Banks no longer have the capacity nor the will to fund projects that often require large investments and serious risks. An example comes from Belgium, where C-Power, the company planning to build the first large-scale farshore wind power farm, cannot implement its project due to a lack of cash. It asks the government for a bailout.

C-Power plans to build a 300MW wind farm on the Thornton Bank in the North Sea, some 27 to 30km offshore. The plant would gradually become a crucial nexus that weaves other future wind farms in North-Western Europe together. The first farm consists of 30 giant wind turbines, 6 of which are under construction. These first 6 turbines were financed by Dexia Bank, one of the banks that ran into difficulties and were bailed out by the Belgian government.

C-Power does not find the money to build the other 24 turbines. In total, the company needs around €850 million for the entire project, of which €152m was found before the credit crisis broke out. Today, no bank is willing to put up the remainder. Borrowing more than half a billion euros is not a small operation, especially in a landscape of bailed-out banks that are still fragile. According to Filip Martens, C-Power's CEO, the project will collapse if the money cannot be found by april of next year.

The wind power company is therefor asking for a large package of government assistance - a question that is dividing the country. C-Power suggests tapping the SynATOM Fund, a multi-billion euro government fund created to finance the future the phase-out of Belgium's nuclear power plants and to store radioactive waste. SynATOM contains €5.2 billion, and is based on a tax paid by all electricity consumers in the country. Belgians have been paying this tax for years, with the specific aim to build up cash to finance the nuclear phase out. The fund was not intended to subsidize or provide loans to private companies.

However, there are many people in favor of supporting C-Power with cash from SynATOM. The reasons are that the nuclear phase out is only planned for the medium term, so the fund can still be rebuilt after the worst of the credit crunch is over. Meanwhile, investing in renewables is an action that can't wait - tackling climate change and energy insecurity requires initiatives today. What is more, C-Power is asking for a loan, which it will repay with interest, - not for a subsidy. Finally, two other energy companies, active in the fossil fuel sector, have been given access to money from SynATOM in the past, so there is no reason why the government shouldn't support a green energy company:
:: :: :: :: :: :: :: :: ::

The C-Power case shows that investments in the renewables sector are still seen as high-risk, and are not given priority by the financial institutions. This despite the fact that all studies and projections indicate that green projects make very good business sense and are guaranteed strong returns over the medium term - even when taking into account the credit crunch and a recession.

Declining oil, gas and coal prices may play a role in the reluctance of banks to step into renewables today. But here too the price collapse is only a temporary phenomenon. Most recently, the IEA, the West's energy watchdog, issued a strong warning that fossil fuel based energy prices will soon begin to rise again to levels seen before the credit crisis.

Picture: In limbo: the giant concrete foundations that will be placed on the sea-bed and on which the wind turbines would be build. Credit: C-Power.


De Standaard: Geen geld meer voor windpark [No more cash for wind farm] - November 12, 2008.

De Redactie: Banken geven geen geld meer voor wind park [Banks refuse to give money for wind farm] - November 12, 2008.

Article continues

Tuesday, November 11, 2008

The man who captures CO2 - interview with SINTEF's Karl Anders Hoff

CO2 capture and storage is one of the leading points on the world agenda this year. Unless we can find a technology that can capture this problematic greenhouse gas and put it away safely, we are going to be in serious trouble. Only a few days ago, leading climate scientists told us we need to reduce atmospheric CO2 levels to 350ppm, down from the current 384ppm. This is a tremendous challenge. Capturing CO2 from coal plants is a key step to achieve this goal.

Interestingly, if carbon capture and storage (CCS) technologies are developed successfully, they can also be applied to biomass power plants, which would then yield carbon-negative energy - that is, energy which actively removes CO2 from the atmosphere. According to the Bellona Foundation, one of Europe's leading environmental think tanks, carbon-negative bioenergy is the single biggest 'wedge' in scenarios aimed at drastically reducing carbon emissions. This type of 'negative emissions' energy can reduce more CO2 than all other renewables combined. This is so because traditional renewables are 'carbon-neutral' at best, never carbon-negative (previous post). In short, CCS, often associated with the coal industry, can actually become our greatest tool in tackling the climate crisis if we apply it to biomass power plants.

Karl Anders Hoff, who works at SINTEF (Scandinavia's largest research organisation) is one of the key scientists driving this debate on CCS technologies. Carbon capture has been his exclusive field of study ever since the nineties, when he was working on his MSc thesis at the Norwegian University of Science and Technology (NTNU).

Now Anders Hoff is project manager for SOLVit, an eight year-long research and development programme on CCS financed by Gasnova and the Norwegian industrial company Aker Clean Carbon, which is also coordinating the programme. With a total budget of NOK 317 million (€36/US$46m), the project is one of the biggest in the world of its type.

Note that Aker Clean Carbon is already seeing the potential of coupling CCS to bioenergy. It has already developed a "Just Catch Bio" technology (previous post) that yields carbon-negative energy (picture, click to enlarge).

Hoff and his colleagues at SINTEF are developing chemical scrubbing processes for capturing carbon dioxide, the greenhouse gas that is spewed out by factories and as flue gases from coal and gas-fired power stations. It is estimated that the 4000 largest such plants in the world are responsible for 40 percent of global anthropogenic CO2 emissions to the atmosphere. The aim of SOLVit is to lower the costs of CO2 capture and storage.

In this interview, Hoff explains the challenges ahead for CCS and the progress being made under SOLVit.

You aren’t starting completely from scratch, are you?
Hoff: No, SOLVit is a result of a number of our previous CO2 projects. These have shown us which direction we ought to be going in, and that it is necessary to work in several fields and on many levels.

As a result, several of the scientists in my department are now working on CO2. At the moment, there are 17 of us in a special team, and since this project is due to continue for eight years, there will probably be more in the future.

So it is still too expensive to capture CO2 today?
Hoff: Yes, the process requires too much energy. A power station that is generating electricity loses about 15 – 20 percent of its output by capturing CO2 . which is sufficient to make it unprofitable. A CO2 capture plant also needs a high level of investment. These costs mean that CO2 capture is not being implemented, and this is what we have to do something about.

What is the solution?
Hoff: The key lies in the chemicals used. These have to be capable of binding CO2, but not so strongly that the gas cannot be released later on. Compounds called amines are used today, but we are looking for other chemicals that have more suitable characteristics:
:: :: :: :: :: :: :: :: ::

How does this happen?
Hoff: We are talking about cold flue gases from a gas-fired power station, that need to be “scrubbed” of CO2. The flue gases flow through a pipe or column, into which chemicals are sprayed at the top so that they can diffuse through the gas and bind to the CO2. The CO2-rich liquid gathers at the bottom of the pipe, after which it needs to be boiled in order to separate out 99.9% pure CO2, while the chemical mix is recycled in order to capture more CO2. Processes of this sort are widely used today to scrub industrial flue gases, but never on the scale that would be needed for a plant that deals with the CO2 from a coal- or gas-fired power plant.

Have you identified good new chemicals?
Hoff: We are on the way there, and we have ideas for chemicals that will reduce energy requirements by 50 percent. The challenge lies in “having our cake and eating it”; i.e. finding chemicals that can react rapidly with CO2 while also needing little energy to release the CO2 from them afterwards. Perhaps what we need is a liquid that captures CO2 and then separates into two different phases, or one that turns the gas into a solid.

A brand-new test plant should help you there?
Hoff: Yes, as part of the programme, we are building a large laboratory at Tiller in Trondheim at a cost of NOK 42 million. SINTEF is putting in 25 percent of the cost of the lab from its own funds. This will be a unique pilot-scale facility, with a 33 metre-high tower and a 25 metre-high scrubbing column, the sort of height that would be needed in an industrial scrubber. This will give us useful results. We can check whether the chemicals that we use are broken down in the long run, and whether they are hazardous waste.

What does your timetable for the future look like?
Hoff: SOLVit will work on both short and long-term solutions, and the project is divided into three phases. Within the next few years, first-generation capture plants will be built in Norway, the UK and Germany. In Norway and the UK the state will support the construction of these plants, and potential suppliers are already tendering for the job in Norway. We already have a new chemical ready, which is due to be tested while we are developing other new contenders. We will also start work on longer-term solutions for second and third-generation plants.

SINTEF: SOLVit - Major research programme for CO2-capture.

SINTEF: Materials and Chemistry, Dept. of Process Technology.

NTNU-SINTEF: Gas Technology Center.

Carbon capture & storage association.

IPCC: Special Report on Carbon Dioxide Capture and Storage.

IEA: CO2 Capture and Storage.

Aker Clean Carbon.

Oscar Fr. Graff, "Aker Clean Carbon: CO2 capture technology and activities" [*.pdf], Chief Technical Officer, Aker Clean Carbon, - August 25, 2008

Biopact: Scientists suggest carbon dioxide levels already in danger zone - urge investments in carbon-negative energy, biochar - November 10, 2008

Biopact: Carbon-negative bioenergy making headway, at last - June 06, 2008

Biopact: Carbon-negative bioenergy recognized as Norwegian CO2 actors join forces to develop carbon capture technologies - October 24, 2007

Article continues

Monday, November 10, 2008

Scientists suggest carbon dioxide levels already in danger zone - urge investments in carbon-negative energy, biochar

If climate disasters are to be averted, atmospheric carbon dioxide (CO2) must be reduced below the levels that already exist today, according to a study published [*.pdf, open access] in Open Atmospheric Science Journal by a group of 10 scientists from the United States, the United Kingdom and France. Reducing atmospheric CO2 levels is only possible by means of carbon sequestration and the production of carbon-negative bioenergy. In practise, the scientists urge us to end coal emissions and at the same time launch bioenergy with carbon sequestration systems, tree planting campaigns, anti-deforestation efforts and biochar initiatives. Ordinary renewables like wind and solar can help, but they do not suffice because they are merely 'carbon-neutral' and are incapable of actively withdrawing CO2 from the atmosphere.

The authors, who include two Yale scientists and NASA's Dr James Hansen, assert that to maintain a planet similar to that on which civilization developed, an optimum CO2 level would be less than 350 ppm — a dramatic change from most previous studies, which suggested a danger level for CO2 is likely to be 450 ppm or higher. Atmospheric CO2 is currently 385 parts per million (ppm) and is increasing by about 2 ppm each year from the burning of fossil fuels (coal, oil, and gas) and from the burning of forests.
This work and other recent publications suggest that we have reached CO2 levels that compromise the stability of the polar ice sheets. How fast ice sheets and sea level will respond are still poorly understood, but given the potential size of the disaster, I think it's best not to learn this lesson firsthand. - Mark Pagani, Yale professor of geology and geophysics
The statement is based on improved data on the Earth's climate history and ongoing observations of change, especially in the polar regions. The authors use evidence of how the Earth responded to past changes of CO2 along with more recent patterns of climate changes to show that atmospheric CO2 has already entered a danger zone.

According to the study, coal is the largest source of atmospheric CO2 and the one that would be most practical to eliminate. Oil resources already may be about half depleted, depending upon the magnitude of undiscovered reserves, and it is still not practical to capture CO2 emerging from vehicle tailpipes, the way it can be with coal-burning facilities, note the scientists. Coal, on the other hand, has larger reserves, and the authors conclude that "the only realistic way to sharply curtail CO2 emissions is phase out coal use except where CO2 is captured and sequestered."

In their model, with coal emissions phased out between 2010 and 2030, atmospheric CO2 would peak at 400-425 ppm and then slowly decline. The authors maintain that the peak CO2 level reached would depend on the accuracy of oil and gas reserve estimates and whether the most difficult to extract oil and gas is left in the ground.

The authors suggest that reforestation of degraded land and improved agricultural practices that retain soil carbon - especially biochar systems - could lower atmospheric CO2 by as much as 50 ppm. They also dismiss the notion of "geo-engineering" solutions, noting that the price of artificially removing 50 ppm of CO2 from the air would be about $20 trillion. Instead, the scientists suggest the following actions:
Desire to reduce airborne CO2 raises the question of whether CO2 could be drawn from the air artificially. There are no large-scale technologies for CO2 air capture now, but with strong research and development support and industrial scale pilot projects sustained over decades it may be possible to achieve costs ~$200/tC or perhaps less. At $200/tC, the cost of removing 50 ppm of CO2 is ~$20 trillion.

Improved agricultural and forestry practices offer a more natural way to draw down CO2. Deforestation contributed a net emission of 60±30 ppm over the past few hundred years, of which ~20 ppm CO2 remains in the air today.

Reforestation could absorb a substantial fraction of the 60±30 ppm net deforestation emission.

Carbon sequestration in soil also has significant potential. Biochar, produced in pyrolysis of residues from crops, forestry, and animal wastes, can be used to restore soil fertility while storing carbon for centuries to millennia. Biochar helps soil retain nutrients and fertilizers, reducing emissions of GHGs such as N2O. Replacing slash-and-burn agriculture with slash-and-char and use of agricultural and forestry wastes for biochar production could provide a CO2 drawdown of ~8 ppm or more in half a century.

[In the Supplementary Material Section] we define a forest/ soil drawdown scenario that reaches 50 ppm by 2150. This scenario returns CO2 below 350 ppm late this century, after about 100 years above that level.

More rapid drawdown could be provided by CO2 capture at power plants fueled by gas and biofuels [that is: carbon-negative bioenergy]. Low-input high-diversity biofuels grown on degraded or marginal lands, with associated biochar production, could accelerate CO2 drawdown, but the nature of a biofuel approach must be carefully designed.

A rising price on carbon emissions and payment for carbon sequestration is surely needed to make drawdown of airborne CO2 a reality. A 50 ppm drawdown via agricultural and forestry practices seems plausible. But if most of the CO2 in coal is put into the air, no such “natural” drawdown of CO2 to 350 ppm is feasible. Indeed, if the world continues on a business-as-usual path for even another decade without initiating phase-out of unconstrained coal use, prospects for avoiding a dangerously large, extended overshoot of the 350 ppm level will be dim.
:: :: :: :: :: :: :: :: :: ::

While they note the task of moving toward an era beyond fossil fuels is Herculean, the authors conclude that it is feasible when compared with the efforts that went into World War II and that "the greatest danger is continued ignorance and denial, which could make tragic consequences unavoidable."

There is a bright side to this conclusion. Following a path that leads to a lower CO2 amount, we can alleviate a number of problems that had begun to seem inevitable, such as increased storm intensities, expanded desertification, loss of coral reefs, and loss of mountain glaciers that supply fresh water to hundreds of millions of people. - James Hansen, lead author, Columbia University

In addition to Hansen and Pagani, authors of the paper are Robert Berner from Yale University; Makiko Sato and Pushker Kharecha from the NASA/Goddard Institute for Space Studies and Columbia University Earth Institute; David Beerling from the University of Sheffield, UK; Valerie Masson-Delmotte from CEA-CNRS-Universite de Versaille, France Maureen Raymo from Boston University; Dana Royer from Wesleyan University and James C. Zachos from the University of California at Santa Cruz.

Graph: Atmospheric CO2 if coal emissions are phased out linearly between 2010 and 2030, calculated using a version of the Bern carbon cycle model. Credit: Hansen, et al/Open Atmospheric Science Journal.

James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Robert Berner, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos, "Target Atmospheric CO2: Where Should Humanity Aim?", Open Atmospheric Science Journal, Volume 2, 217-231 (2008), doi: 10.2174/1874282300802010217 [alternative link to the paper].

Dr James E. Hansen

Mark Pagani, Yale University: Geology and geophysics

Robert Berner

Article continues

Scientists find key genes to convert annual crops into perennials

Scientists from the Flanders Institute of Biotechnology (VIB), a world leading crop science institute, have discovered that only 2 genes make the difference between herbaceous plants and trees. They tested their knowledge and discovered that annual crops can easily be converted into perennials. They succeeded in tweaking a typical annual plant - thale cress - in such a way that it generated wood formation, and became a shrub-like perennial. The findings, published in Nature Genetics, may help create a more sustainable future for world agriculture.

A key step in the evolution of farming consisted of domesticating and breeding wild seed crops, by trial and error. The greatest transformation happened thousands of years ago, when man successfully converted perennial seed crops (like Zea diploperennis, perennial maize) into annual crops that yield more grain (Zea mays, modern corn). Out of this transformation came grain-based food systems and diets, that still persist today and which form the basis of modern agro-industry. Agrobusiness has generated a system almost entirely based on monocultures of these annuals.

This agroindustrial model of production is now up for revision, as it requires a large amount of environmentally damaging inputs (pesticides, herbicides, fertilizers). Annual crops mine soils and contribute only weakly to the maintenance of ecosystem services. This is why ecologically responsible agronomists are taking a look back at perennials, which stabilize soils, sequester carbon, manage water more efficiently and are less prone to diseases, pests and climatic stresses.

Bioenergy researchers as well are fascinated by perennials. A small number of leading scientists even thinks it might be possible in the future to design ultimate crops that perform a multitude of desirable functions simultaneously. These futuristic crops would yield grains for human consumption, a large amount of above-ground biomass that can be harvested for energy, and a below-ground biomass that remains active and automatically regrows the plant after harvest. The crops would simultaneously provide food, fiber and fuel, while restoring ecosystems and without relying on expensive and polluting inputs.

Thus, the future of agriculture may be one that goes back to its earliest stages: a return to perennials. The Flemish scientists now made a breakthrough that could make this transition possible:
:: :: :: :: :: :: :: :: :: ::

Annual crops grow, blossom and die within one year. Perennials overwinter and grow again the following year. The life strategy of many annuals consists of rapid growth following germination and rapid transition to flower and seed formation, thus preventing the loss of energy needed to create permanent structures. They germinate quickly after the winter so that they come out before other plants, thus eliminating the need to compete for food and light. The trick is basically to make as many seeds as possible in as short a time as possible.

Perennials have more evolved life strategies for surviving in poor conditions. They compose perennial structures such as overwintering buds, bulbs or tubers. These structures contain groups with cells that are not yet specialised, but which can later be converted when required into new organs such as stalks and leaves.

Annual crops consume all the non-specialised cells in developing their flowers. Thus the appearance of the flower signals means the end of the plant. But fortunately they have left seeds that sense – after winter – that the moment has come to start up. Plants are able to register the lengthening of the days. With the advent of longer days in the spring, a signal is sent from the leaves to the growth tops to activate a limited number of blooming-induction genes.

Deactivating two genes
The VIB scientists, in particular Siegbert Melzer, who works in Tom Beeckman's research group, have studied two such flower-inducing genes. They have deactivated them in thale cress (Arabidopsis thaliana), a typical annual. The VIB researchers found that mutant plants can no longer induce flowering, but they can continue to grow vegetatively or come into flower much later. Melzer had found that modified crops did not use up their store of non-specialised cells, enabling perennial growth. They can therefore continue to grow for a very long time.

As with real perennials these plants show secondary growth with wood formation creating shrub-like Arabidopsis plants.

Researchers have been fascinated for a long time by the evolution of herbaceous to woody structures. This research clearly shows only two genes are in fact necessary in this process. This has probably been going on throughout the evolution of plants. Furthermore it is not inconceivable this happened independently on multiple occasions, the researchers say.

Picture: ordinary annual Arabidopsis thaliana plant to the left; to the right, wood formation in modified, 'perennial' Arabidopsis. Credit: VIB, Nature Genetics.

Melzer S, Lens F, Gennen J, Vanneste S, Rohde A, Beeckman T. "Flowering time genes modulate meristem determinacy and lead to growth form and longevity in Arabidopsis", Nature Genetics, 09 November 2008; | doi:10.1038/ng.253

Article continues

Sunday, November 09, 2008

Integro Earthfuels plans first torrefaction plant in the U.S.

In a fascinating development, Integro Earthfuels is planning to build its first of ten commercial torrefaction plants in the US. Torrefaction of biomass is one of the most promising bioenergy technologies, because it transforms bulky biomass into a high-quality product that can be readily co-fired with coal, without the need to change anything to a coal plant. Torrefied biomass allows us to 'take over' dirty coal plants, and convert them to entirely green power facilities, without the need to build new infrastructures or dedicated power plants.

More than half of all the electricity produced in the US comes from coal fired utilities. Coal is therefor the number one target for CO2 reduction and the primary industrial cause of global warming. Closing down coal plants is a radical step, but 'sneaking' green energy into them might be a smarter, more transitional process.

Co-firing biomass with coal is being practised widely in Europe, but the technique presents logistical, processing and combustion challenges that limit the fraction of biomass that can be co-fired to around 10-15%. Costs are also relatively high, even though at current coal prices, co-firing raw biomass has become competitive. Building entirely new, dedicated biomass co-generation facilities is an option, but it is more expensive still.

Raw biomass for co-firing has several disadvantages: the fuel is bulky and can therefor only be transported economically over medium distances; it cannot be stored together with coal, but needs new, dedicated infrastructures; the biomass also needs to be crushed or processed in separate facilities to make it ready for co-firing; and finally, given its different combustion properties, it may make the co-firing step itself difficult and require modifications to boilers.

By first torrefying biomass, all these challenges can be overcome in a single stroke (previous post). Torrefied biomass:
  • has a much higher energy density than raw biomass
  • it allows for a dramatic increase in the distance over which the biomass can be transported to the plant (some studies show distances can be squared)
  • because torrefied biomass is hydrophobic, it can be stored in the open, for long times, in the same infrastructures as those used for coal
  • it requires less energy to crush, grind or pulverise torrefied biomass than it takes to crush coal, and the same tools can be used
  • given its excellent combustion properties, the fuel can be readily co-fired with coal
In short, torrefaction is a process that turns raw, bulky, moist biomass into a kind of 'green coal'. Torrefaction is a technology first developed in the coffee processing industry. It boils down to 'roasting' the biomass at temperatures ranging from 200 to 300 °C, in a low oxygen or no-oxygen atmosphere (figure 1, click to enlarge).

The conversion process

Woody biomass - the main feedstock - consists of hemicellulose, cellulose, lignins and extractants (chemicals absorbed during the growing cycle through air and dirt, generally less than 3%) (figure 2, click to enlarge). During torrefaction the molecular structure of the wood is altered, enhancing some of the wood’s physical properties. Torrefaction liberates water and releases volatile organic compounds (VOC) through the devolitization of primarily the hemicelluloses and extractants. The lignins are loosened and have limited devolitization while the cellulose is nearly unimpacted at these temperatures. As the hemicellulose, which binds the cellulose, is burned away, the wood is unbound making it more brittle. This increases the grindability of torrefied wood and makes its handling properties more like coal. This unbinding also releases the last of the water not stored at the cell level, leaving the wood hydrophobic. During the torrefaction process most of the energy value of the wood is preserved with the product losing 20-30% of its mass while retaining 90% of its energy. The calorific value of the wood increases to 9,500-11,500 Btu per pound.

So far, there is only one commercial torrefaction plant operating in the world, located in the Netherlands. It supplies torrefied biomass pellets to large coal-fired power plants, who get a green credit for each ton of biomass they burn. Integro Earthfuels is now planning to open a similar plant in Roxboro County, North Carolina. The $12 million plant will have an initial capacity to produce up to 84,000 tons of torrefied biomass annually:
:: :: :: :: :: :: :: ::

Currently, Integro is finalizing off-take agreements with local utilities and Universities with their own heat and power plants to provide them with a majority of the supply beginning in 2009. Integro will build 10 additional facilities over the next 6 years to meet the demand from coal-fired electricity producers.

Integro lists the following benefits of torrefied biomass for the coal-fired electrical utility:
  1. Each ton of torrefied wood burned in the facility reduces their carbon output by up to 2.4 tons, earning them an estimated $72 in carbon credits.
  2. Torrefied wood can be handled just like coal. It can be placed on the coal pile and processed alongside the coal. It has been tested to 10% and will likely go to 30% mix with coal.
  3. It does not take on water so it can be left uncovered like coal.
  4. It has lower levels of NOx and SOx than coal—primary pollutant emissions by EPA—lowering emissions and associated costs
  5. During the torrefying process, most volatiles are burned off, eliminating the concerns over slagging in the boiler.
  6. Because torrefied wood is handled identically to coal, little or no CapEx is required of the utility.
Integro’s torrefied biomass solution overcomes the limitations previously attributed to biomass co-firing through its unique treatment process. It produces a high-grade, smokeless fuel suitable for co-firing in coal powered electric plants.

CCS no match
Integro's ambition to build 10 plants is not unrealistic. Torrefaction holds a tremendous potential precisely because the fuel it generates can be used directly by existing coal plants and requires little, if any, capital investment on the part of utilities.

Coal plants need to clean up their act, and their only option is to make massive investments into untested carbon capture and sequestration (CCS) technologies.

Switching to torrefied biomass offers a much more competitive option, requiring none of these investments. According to Integro, the fuel can already be delivered below the cost of coal when carbon credits are factored in. This will allow coal-fired utilities to meet their clean energy obligations without a significant increase in the cost of electricity to consumers.


Roxboro Courrier: Commission must authorize special use permit before ‘green coal’ plant can be built - November 8, 2008.

Integro Earthfuels: co-firing torrefied biomass with coal.

Biopact: Dutch partners agree to build commercial scale biomass torrefaction plant - November 12, 2007

Biopact: Torrefaction gives biomass a 20% energy boost, makes logistics far more efficient - July 25, 2008

Biopact: Study: solid biofuels 570% more efficient than corn ethanol in reducing GHG emissions - September 10, 2008

Article continues