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climate change

Technology versus global warming

Brazil takes the lead with ethanol, biodiesel and direct planting

EDUARDO CESAREthanol: 325 refineries produce 17 billion liters, 35% of the world totalEDUARDO CESAR

The three reports by the Inter-governmental Panel on Climate Change (IPCC), published in March, April and May and the largest environmental X-ray taken so far left no doubts that the increase in the planet’s temperature has to be attributed to the actions of man and that the impact of global warming on ecosystems, the economy and societies may cost humanity dear. But they also pointed out the path to be taken: the world can reduce greenhouse gas emissions, mainly carbon dioxide (CO2), by taking mitigating measures, among which are the use of renewable energy, rationalization of the use of transport, improvements in agricultural management and reductions in vegetation clearance. Action, however, must be taken immediately.

“This is an excellent moment to change consumption patterns in order to meet the demands for sustainability and to change our vision on the use of the planet’s natural resources”, says Paulo Artaxo, seeing an opportunity, above all for Brazil, in something that might be interpreted as a crisis. According to Artaxo, the country has “enormous strategic advantages” in relation to all of the IPCC’s recommendations.

The list of “strategic advantages” begins with ethanol and includes biodiesel, direct planting technology and the production of electricity from renewable sources. Brazil has been developing ethanol technology for the last 30 years, has more than 6 million hectares of sugarcane and produces 17.7 billion liters of ethanol a year, around 35% of the world’s total, in its 325 sugar-alcohol refineries. Productivity varies between 6,000 and 8,000 liters of ethanol per hectare. Nearly 90 new refineries are currently being installed and almost 200 are at the study stage, half of them with foreign participation, which should extend the planted area by more than 1 million hectares and increase the supply of this fuel to 27.8 billion liters by 2010.

Brazil and the United States, with a production of 18.5 billion liters of ethanol from corn, account for 70% of the global ethanol market. The Brazilian market already has good expansion prospects. Domestic consumption is growing with flex-fuel automobiles – which are expected to increase by 50% by 2010, as calculated by the Sugarcane Industry Union (Unica) – and with the compulsory Brazilian alcohol/gasoline mixture rules. The international market is still in its infancy and volatile, as Marcos Jank, president of the Institute for Trade and International Negotiations (Icone) usually describes it. There are growth prospects for Brazilian alcohol exports, which last year totaled 3.5 billion liters, to the Japanese and Asian markets, for example. The possibility of trade with the United States comes up against the protectionist tariff of US$ 0.14 per liter and that country’s willingness to dig deep into its pockets in order to supply its domestic market: US$ 1.9 billion is being invested in corn ethanol research. According to the experts, Brazil should place its bets on exporting its ethanol production technology to countries in Africa, Asia and Latin America that produce cane, but use little technology, and have energy shortages.

But to do so it is necessary to rise to some of the challenges. According to data from Única, over the last 20 years sugarcane producers have invested US$ 40 million a year in plantation productivity, which is growing at an average of 4% a year. In the Ribeirão Preto region, for example, it is already 90 tons per hectare. “But cane has the potential to produce  180 to 200 tons a hectare”, says the president of the Brazilian Agriculture and Livestock Research Company (Embrapa) , Silvio Crestana.

Ethanol from cellulose
The production of sugar and fuel alcohol only makes use of one third of the biomass from sugarcane. The chief challenge is also to convert the cellulose that is in the bagasse and straw discarded during the harvest into alcohol, by means of enzymatic hydrolysis. The research is currently being carried out as part of the Bioethanol Project, which is coordinated by the Energy Planning Inter-disciplinary Nucleus (Nipe), at  the State University of Campinas – Unicamp (see Pesquisa FAPESP 133). The new technology is expected to bring about a surge in productivity without extending the sugarcane plantation areas.

It is also necessary to solve the issue of inputs and other products in order to reduce cane production costs. “We’re importers of phosphorous, potassium and even nitrogen, all of which depend on multilateral and bilateral agreements”, Crestana recalls. He notes that important advances in agrobiology have already been achieved in the case of nitrogen. “We’ve already managed to supply up to 30% of the needs of grasses, such as sugarcane, biologically”, says Embrapa’s president. There are also investigations under way into how to obtain the product from potassium and phosphorous bearing rocks. “The problem is how to do this in an economically viable way”, says Pedro Leite da Silva Dias, a climate change expert from the Institute of Advanced Studies (IEA) at the University of São Paulo (USP).

EDUARDO CESARBiodiesel: 23 refineries produce 964 million litersEDUARDO CESAR

Sugarcane management is also a problem, points out Reynaldo Victória, from the Center for Nuclear Energy in Agriculture,  the Luiz de Queiroz School of Agriculture (Esalq), at the University of São Paulo (USP). Cane is harvested after the plant has been burned, but if it were to be cut without  burning the refuse would be incorporated into the soil and transformed into organic raw material. In this case the balance of CO2 captured during the process of transforming sugarcane into alcohol produces even better results. “Trials conducted in refineries have already shown results that are 40 tons per hectare better over an average term of ten years”, says Victória. The challenge in this case is to develop the technology to harvest the cane in its unburned state: mechanical harvesters only operate on land that has a slope of up to 12º and manual cutting would be impossible, unless the workers used special equipment. “This would make harvesting much more expensive”, observes Victória.

Another problem with burning – a practice also used in Brazil for clearing the soil – is that it produces gases that are the precursors of ozone and which, in contact with light, accumulate this greenhouse gas in the troposphere, adds Silva Dias.

Carbon capture
One of the IPCC recommendations for the reduction of global warming is to adopt direct planting, which thanks to the elimination of plowing, does not turn over the soil, thereby maintaining the accumulated straw  and consequently the carbon is retained in the vegetable matter. “This is a technique used in high latitudes and that Brazilian agriculture has adapted”, observes Silva Dias.

Brazil has 24 million hectares that have been cultivated in the form of direct planting; This represents 30% of the country’s total crop area in. It is the second largest cultivated area using this technology after the United States, with its 26 million hectares. “Direct planting was adopted to reduce soil erosion”, explains Carlos Eduardo Pellegrino Cerri, from Esalq’s Soil Department. It is now known that it “captures” the carbon in the soil. Studies have shown that half a ton of CO2 per hectare is incorporated into the soil every year as a result of direct planting. “If we multiply this by the planted area of 24 million hectares, the result is 12 million tons of carbon a year”, Cerri calculates.

In a tropical country this practice would result in a monumental storing of this greenhouse gas. The major challenge science must face is to reduce the storage of nitrous oxide in the soil as well because it is one of the greenhouse gases and one with an enormous potential for global warming; it is to be found in nitrogen-based fertilizer waste, which is also incorporated into the soil. Research has revealed that this negative effect can be lessened by splitting the application of fertilizers.

“The carbon captured in the soil could be transformed into a source of revenue for the producer if it were sold as part of the clean development mechanism (CDM)”, suggests Cerri. CDM is a tool created by the Kyoto Protocol that allows the developed countries, which have emission reduction targets to meet by 2012, to acquire the carbon credits generated by projects for reducing greenhouse gas emissions in developing countries. Worldwide, more than 50 countries are developing CDM projects. Today Brazil ranks third, with 210 projects, behind China, with 299, and India, with 557. Carbon captured in the soil is not accredited for this market. “This will depend on government negotiations to be ratified as from 2012, in the period known as post-Kyoto.”

The fuel of the future
Since 1975 Brazil has also been researching biodiesel. There are 23 biodiesel processing plants functioning, with capacity for producing 964 million liters. The fuel is used as an** additive 2% mixture in all the diesel oil sold in Brazil; this will become mandatory as from 2008.

But there is still a long road to travel in developing this technology, since almost all the biodiesel produced in Brazil is made from methanol, which strictly speaking is not considered renewable (see Pesquisa FAPESP 134).

“We have to make the transition to bio-fuel. This is technology that we have not fully mastered”, points out Silva Dias. With productivity of between 1,500 and 3,000 liters per hectare, biodiesel is much less efficient than ethanol, with between 6,000 and 8,000 per hectare, and lower than in countries such as Indonesia, which produces fuel from red palm oil (dende) with surprising results: 5,000 liters per hectare.

We need to make “great strides in both the research and the technology”, he recommends, and among other things investigate the performance of palm trees planted over large areas in order to analyze their real contribution to reducing greenhouse gases.

Renewable inputs
In terms of renewable inputs for producing electricity, Brazil is also in an advantageous position. Artaxo remembers that Brazil has excellent prospects to explore the generation of solar and wind power. “This is priceless”, he emphasizes.

In the opinion of José Goldemberg, from USP’s Electrical Energy Institute, Brazil’s chief alternative continues to be hydroelectric power. “The energy potential used in the country is a mere 30%”, he says. He recognizes that the major hydroelectric sources are currently concentrated in the North of Brazil. Such is the case of two hydroelectric power stations on the Madeira River, Santo Antônio and Jirau, construction of which is awaiting authorization from the Brazilian Institute of Renewable Natural Resources (Ibama). However, in Goldemberg’s opinion, the country should invest in constructing small hydroelectric power stations, with capacity of up to 1,000 MW, which are today restricted to the Alternative Energy Sources Incentive Program (Proinfa). “We’ve got the technology to do this”, he stresses.

Proinfa, however, is dragging its feet and its results leave a lot to be desired. The program was set up in 2002 with the aim of supporting investments in wind sources, small hydroelectric power stations and biomass. The target was to reach installed capacity of 3,300 MW, but results have not exceeded 860 MW. Wind generators account for 208.3 MW and the small hydroelectric power stations, 186.4 MW. The country already has the technology, but the major challenge, according to Artaxo, is to give this production some scale. “The government doesn’t have the finances or the logistics to implement this new energy market. Its task must be to encourage investments and leave the business up to private initiative.”