Decade-long experiment suggests limitations to carbon dioxide 'tree banking'

Scientists recently found that forests in mid- to upper-latitude regions are less effective carbon sinks than previously thought, while others have stressed that many commercial carbon offsetting schemes based on tree-planting campaigns are often not effective - much depends on the type of trees, local ecosystem characteristics and the location of the site (earlier post). The results of a 10 year experiment in the U.S. now suggest that there are indeed clear limitations to carbon dioxide 'tree banking'.

While a decade of bathing North Carolina pine tree stands with extra carbon dioxide did allow the trees to grow more tissue, only those pines receiving the most water and nutrients were able to store significant amounts of carbon that could offset the effects of global warming, scientists told a national meeting of the Ecological Society of America (ESA).

These results from the 10 year-long Free Air Carbon Enrichment (FACE) experiment in a Duke University forest suggest that proposals to bank extra CO2 from human activities in such trees may depend on the vagaries of the weather and large scale forest fertilization efforts.

If water availability decreases to plants at the same time that carbon dioxide increases, then we might not have a net gain in carbon sequestration. In order to actually have an effect on the atmospheric concentration of CO2, the results suggest a future need to fertilize vast areas. And the impact on water quality of fertilizing large areas will be intolerable to society. Water is already a scarce resource. - Ram Oren, FACE project director, professor of ecology, Duke's Nicholas School of the Environment and Earth Sciences.

In a presentation delivered on Tuesday, Aug. 7 by Heather McCarthy, Oren's former graduate student, eight scientists working at the FACE site reported on the daily administrations of 1 1/2 times today's CO2 levels and how it has changed carbon accumulations in plants growing there.

The Department of Energy-funded FACE site consists of four forest plots receiving extra CO2 from computer-controlled valves mounted on rings of towers, and four other matched plots receiving no extra gas.

Trees in the loblolly pine-dominated forest plots that were treated produced about 20 percent more biomass on average, the researchers found. But since the amounts of available water and nitrogen nutrients varied substantially from plot to plot, using averages could be misleading:
energy :: sustainability :: biomass :: bioenergy :: climate change :: carbon dioxide :: trees :: forests :: carbon cycle :: carbon sequestration :: carbon sink ::

"In some areas, the growth is maybe 5 or 10 percent more, and in other areas it's 40 percent more," Oren said. "So in sites that are poor in nutrients and water we see very little response. In sites that are rich in both we see a large response."

The researchers found that extra carbon dioxide had no effect on what foresters call "self thinning" -- the tendency of less-successful trees to die off as the most-successful grow bigger.

"We didn't find that elevated CO2 caused any deviation from this standard relationship," said McCarthy, now a postdoctoral fellow at the University of California, Irvine.

Also unchanged by the CO2 enrichment were the proportions of carbon atoms that found their way to various components of plant systems -- wood, leaves, roots and underlying soil. Only a few of those components will store carbon over time, noted Oren and McCarthy.

"Carbon that's in foliage is going to last a lot shorter time than carbon in the wood, because leaves quickly decay," McCarthy said. "So elevated CO2 could significantly increase the production of foliage but this would lead to only a very small increase in ecosystem carbon storage."

Other FACE researchers contributing to the ESA report were Kurt Johnsen of the U.S. Department of Agriculture's Forest Service, Adrien Finzi of Boston University, Seth Pritchard of the University of Charleston, Robert Jackson and Charles Cook of Duke and Kathleen Treseder of the University of California, Irvine.

Picture: At FACE, computer-controlled valves on rings of towers are administering carbon dioxide to stands of loblolly pines. Credit: Chris Hildreth, Duke University.

References:
Eurekalert: Experiment suggests limitations to carbon dioxide 'tree banking' - August 7, 2007.

Duke University FACE research site.

Brookhaven National Laboratory FACE site.

Oak Ridge National Laboratory FACE site.

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China's Dragon Power to raise US$2 billion for 100 biomass power plants

According to information obtained by the South China Morning Post, Dragon Power, a Beijing-based company that generates power from biomass, plans to raise as much as 15 billion yuan (€1.45/US$2bn) from an initial public offering in Hong Kong next year to build not less than 100 biomass power plants across the People's Republic.

China last month increased its targets for bio-power and biofuels (earlier post), and launched an ambitious bioenergy program based on forestry, which, amongst other benefits, helps fight desertification, will reduce coal consumption by 10% and is expected to bring large-scale employment opportunities to the country's vast rural population (previous post). Under the new vision, bioenergy will make up almost 25% of the nation's energy consumption by 2020. As China has become the world's largest emittor of greenhouse gases from fossil fuels (especially coal), development of the biomass sector is seen as a top priority to limit the country's contribution to climate change (an overview of China's biomass power plans and plants here, and here).

Dragon Power this year began generating energy at biomass power plants in Hebei and Shandong provinces, according to a June report in the mainland magazine New Economic Guidance (map), run by the information centre of China's State Council Development and Research Centre.

The alternative power producer started a 50-50 joint venture called National Bio Energy in 2005 with Shenzhen State Power Scientech Development, a subsidiary of the State Grid Corporation, the nation's largest power transmission company. In april of this year, the companies surpassed a symbolic mark when they produced more than 100 million kWh of carbon-neutral electricity. Further, the joint-venture recently started cooperating with bioenergy companies in Sweden to build integrated green power plants there.

Now Dragon Power and National Bio Energy plan to open more than 100 biofuel power plants across the mainland by 2010, generating more than 200 megawatts of capacity, according to the report which cited Jiang Dalong, the president of Dragon Power and a vice-president of National Bio Energy.

The government has so far approved the construction of 29 electricity generation plants driven by biomass, said another executive cited in the report:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: electricity :: climate change :: coal :: China ::

US Citibank invested US$150 million in Dragon Power earlier this year, a source said. Citibank declined to comment.

Dragon Power has a distribution contract with State Grid, which made the company attractive to foreign investors, the source said.

State Grid is the country's largest electricity distributor and operates in 26 provinces. China Southern Power Grid distributes energy in five provinces.

The mainland's power grids are required to buy all available power generated from alternative sources from September 1, the State Electricity Regulatory Commission said on its website this month.

The government plans to have 16 per cent of total electricity supply generated by renewable sources by 2020, at a cost of US$198 billion in investment. Coal generates 78 per cent of all mainland-produced electricity.

Beijing in June stopped approving new corn-based fuel ethanol plants amid fears rising grain prices would boost inflation. Ethanol is most commonly used as a car fuel.

Dragon Power uses straw and wood chips to make the fuel used in its power plants, it says on its website.

China Agri-Industries Holdings, which raised HK$3.2 billion in its listing on the Hong Kong stock market in March, had planned to build four corn-based fuel ethanol plants with an annual capacity of 900,000 tonnes. It said it was now switching to sweet potatoes as a biofuel source.

Non-food crops such as sweet potatoes and wood are not affected by the new rule. The four plants are due to begin producing energy this year.

Shares of China Agri, a subsidiary of state-owned Cofco, have risen 27 per cent since listing in March.

Gushan Group, a mainland producer of biodiesel, had planned to raise up to US$200 million from a share sale in Hong Kong last year. That plan was dropped because of uncertainties after new mainland regulations made it more difficult to incorporate assets overseas, although a source said the firm was considering reviving the deal. Biodiesel is a clean-burning fuel produced from animal fats and vegetable oils.

References:
South China Morning Post: Dragon Power plans IPO to raise US$2b for biofuel plants [subscription req'd] - August 7, 2007.

Biopact: China announces 'Agricultural Biofuel Industry Plan': new crops, higher targets - July 04, 2007

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Expert: biofuels will help fight hunger

It has become a bit of a nuisance to read commonplaces about biofuels, such as the idea that they push up food prices or that they are not energy efficient. A more in-depth look at these important issues reveals a far more complex reality. But despite scientists' efforts to bring more nuance into the debate, some myths persist.

One of those is the food versus fuel debate. Biofuels may temporarily increase food prices but this doesn't imply people will starve. On the contrary, higher agricultural prices reduce poverty, boost incomes and thus strengthen the food security of the vast majority of the world's poor, who live in rural areas. Moreover, the question is not whether biofuels make food more expensive, the real thing to ask is: what would happen if we were only to rely on ever more costly oil? The answer is very straightforward: everything would become more expensive, not only food. For the poorest countries the effects are more poverty, hunger and underdevelopment, while the rest of the world may suffer the potentially catastrophic effects of climate change. Biofuels help counter both these dark prospects. Recently, African scientists even went so far as to conclude that biofuels may be key to achieving the UN's ambitious 'Millennium Development Goals' (previous post).

Antonio José Ferreira Simões, director of the Department of Energy of the Ministry of Foreign Affairs of Brazil - a country with vast experience on the social and economic effects of green fuels - writes an interesting essay in the International Herald Tribune, in which he explains why he thinks biofuels will help fight hunger. In an argumentation that resembles our own, Simões takes a broad perspective on the matter:

The first decades of the 20th Century heralded the automobile era. At the time, it was said that it would not be safe to trade the reliability of a horse for the uncertainty of an automobile. After all, the horse was always available and ran on alfalfa, clearly an abundant raw material. It was then too risky to trust gasoline, some argued, since it could become scarce in a few years.

Today, as we are again facing the challenges of changing our energy matrix, it is important to clearly establish what is reality and what is myth regarding biofuels.

The reality is that if we maintain the current rate of oil consumption without major reductions in carbon emissions, we will surely be heading in the direction of unprecedented climate change and natural disasters. It is also a fact that if oil demand continues to increase, prices will skyrocket, terribly affecting poor countries. The International Energy Agency itself admits that increasing demand and irregular supply will impose additional pressure on prices, which in turn will also be affected by higher extraction costs of new reserves (deep waters, heavy and extra-heavy oil). Additionally, the increase in oil prices will have serious consequences on the price of food products. More expensive fertilizers will become less accessible to farmers in poor countries. Sharp increases in transportation costs will reduce the access to food for millions. Therefore, higher oil prices will surely mean less food consumption.

One of the most common myths is that biofuels will necessarily compete with food production. Nowadays, the largest food producers are the developed countries that strongly subsidize their agriculture. In developing countries, with few exceptions, large scale food production does not occur: They simply cannot compete with rich countries' agricultural subsidies. It is more cost-effective to import products offered as food aid from developed countries, or sold at subsidized prices, than to produce locally.

Production of biofuels in developing countries would change this picture. Large extensions of unutilized arable land in the Southern Hemisphere would be employed for highly profitable biofuel-oriented crops, restructuring the agricultural sector. Millions of jobs would be generated, thus increasing income, exports and food purchasing power of the poorest. Furthermore, production of biofuels in the South would help avoid redirecting the use of food-producing land in the North for this purpose:
energy :: sustainability :: ethanol :: biodiesel :: biomass :: bioenergy :: biofuels :: food security :: energy security :: poverty alleviation :: developing world :: Africa ::

In Brazil, biofuels production has grown alongside with increasing food crops. It is lack of income that fuels hunger, not the use of biofuels. Experience has proven that biofuels production generates income, increasing food consumption. The Brazilian ethanol industry generates one million direct jobs and up to six million indirect jobs. Biodiesel benefits 224 thousand low-income families.

Another myth is that the production of biofuels threatens the Amazon rain forest. It should be noted that between 2004 and 2006, a period of strong growth in the Brazilian biofuels production, the Amazon rain forest deforestation rate was reduced by 52 percent. Also, large sugar cane plantations are located at least 1,000 kilometers away from the Amazon region, where it is not possible to efficiently grow sugar cane, due to the high humidity, which prevents saccharose from forming.

Biofuels also could contribute to reduce carbon emissions through the use of degraded lands. In the case of Brazil, we use less than 10 percent of all arable land for sugar cane cultivation. There are, however, 150 million hectares of degraded pasture land that the Brazilian Government is working to recover. This land will receive a vegetal cover from sugar cane, thus contributing to reduce carbon emissions.

In order to ensure that the development of biofuels production takes place while contributing to the improvement of social and environmental conditions, as announced by President Luiz Inácio Lula da Silva, Brazil will organize a national technical, social and environmental certification system. This will allow us to constantly verify the sustainability of our production.

Nowadays, world energy resources are concentrated in 20 countries. Biofuels will allow a true democratization of the international market, as over 100 countries will be producing energy for the world. There is no doubt about the fact that this is a great change, maybe as revolutionary as the one that began in the early 20th Century. After all, the transition from animal traction to petroleum was antipodal to environmental sustainability. Today, we can correct this and, at the same time, contribute to the generation of employment and wealth in the countries of the South - much to the benefit of the global community.

Picture: castor oil farmer in Brazil's arid Nordeste region, where the new biodiesel program currently benefits 60,000 poor rural families. The energy agriculture program boosts both the income and food security of the households. Courtesy: German Agency for Technical Cooperation.

References:
International Herald Tribune: Biofuels will help fight hunger - August 6, 2007.

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Renewable energy jobs calculator

The International Energy Agency's bioenergy program has released a handy tool that calculates the numbers of jobs created by a typical renewable energy project. The 'new jobs calculator' can be found at the Bioenergy Task 29 website, which looks at the socio-economics of biofuels and bioenergy (earlier post), and which contains an educational section. The data and methodology for the calculator are based on work by the Sustainable Energy Ireland initiative. Earlier we compiled our own estimation of 'jobs per joule' generated in different energy sectors, with more details on particular biofuels.

Number of jobs generated for a typical 5MW project initiated in 2007 with an investment worth €2 million, taking 48 months to build and install, with a life-time of 15 years and operating 3600 hours per year. Source: New Jobs Calculator, IEA Bioenergy Task 29

The argument that renewable energy projects often result in a substantial number of jobs for the local economy is important, because it counters the idea that such projects are 'too expensive'. If one goes beyond purely commercial perspectives and one looks at the many indirect socio-economic benefits of renewables projects (their contribution to mitigating climate change, jobs generated, energy diversification and security, etc), then a strong case in their favor can be made and, if necessary, they deserve state support.

Task 32's interactive renewable energy calculator allows the user to give input on the scale of the investment, the construction and installation period, the amount of megawatts installed, the life-time of the plant, the year of installation, ect... These inputs are then used to estimate the equivalent of full time jobs generated in construction and installation as well as in operation and maintenance.

It seems like the ratio of jobs generated in different sectors (solar, wind, hydro, bio) remains fairly constant across parameters: liquid biofuel projects and the production of fuel from dedicated energy crops result in the largest number of jobs (as can be seen in Brazil, where the biofuel sector has generated more employment than any other economic sector over the past few years in the state of São Paulo - more here). Bioenergy made from residues involves no construction and installation phase (the residues can be harvested as such) and thus result in fewer employment opportunities. Other renewables and bioenergy from gasification, combustion and biogas production are somewhere in the middle [entry ends here].
energy :: sustainability :: employment :: biomass :: biofuels :: solar :: wind :: hydro :: energy crops :: bioenergy :: renewables ::

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