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Science for Brazil (Reino Unido)

Brazilian Biofuels ‘to cut global CO2 emissions by 5%’

Publicado em 23 novembro 2017

Brazil’s world-leading ethanol fuel industry has the potential to substitute almost 14% of global oil consumption, in the process reducing global emissions of carbon dioxide by as much as 5.6% by 2045, so breathing new life into the race to meet the climate change targets laid down in the Paris Climate Accords.

The forecast comes from an international study of the climate change implications of biofuels published on October 23 in the research journal Nature Climate Change. The study shows that fuel made with Brazilian sugarcane ethanol may offset 86% of CO2 emissions compared to oil use.

Crucially, the study addresses the “Food Vs. Fuel” dilemma besetting both biofuels and land-based solar power.

The potential under consideration does not involve Brazil’s ethanol production displacing any food crops from existing cultivated land, or extending agro-energy production into sensitive areas like the Amazon or the Pantanal wetlands. By contrast, solar energy advocates in Europe and the US, actively welcome the transformation of ever-larger areas of farmland into silicon solar panel ‘deserts.’

If the science proves correct, the Nature report’s conclusions provide an important strategic alternative for planners seeking to reconcile the long-term energy demands of the transport sector, with the planet’s future health. While transport consumes 27% of all global fossil fuels, the economics and technological status of battery power transportation means it will be decades before carmakers and users can fully dispense with liquid fuels for poorer countries as well as rich nations. In the interim, ethanol is the only viable substitute – and more heavily subsidised and less energy-efficient production of maize alcohol in the United States cannot deliver the volume needed.

By the year 2045, the report says, Brazil could be producing the equivalent of 12.7 million barrels of oil per day in biofuels. That’s equivalent to the output today of Saudi Arabia’s Aramco, the world’s largest oil producer. It also dwarfs Brazil’s own oil production of 3.2 million barrels/day in 2016.

On climate change, the report says, “the corresponding range of CO2 offsets is 0.55–2.0 Gigatons yr−1. This would displace 3.8–13.7% of crude oil consumption and 1.5–5.6% of net CO2 emission globally relative to data for 2014.” Such an achievement would help limit the rise in average  global temperatures to less than two degrees, as agreed by signatories to the Paris Climate Accords.

US scientists from the University of Illinois, Urbana (UIUC) joined Brazilian colleagues from the Universities of São Paulo and Campinas, plus European researchers, to model future energy demands, then matching these against Brazil’s agricultural potential.

These were plotted at the National Center for Supercomputing Applications using software developed at UIUC to simulate Brazil’s agricultural potential under different scenarios.

Researchers first modelled energy production potential making use only of productive farmland suitable for cane planting identified in a 2007 study by Brazil’s EMBRAPA government agency. Then they modelled potential also making use of new arable land not needed for food crops or animal feed (even taking into account future world growth of demand for food). A third scenario involved additional cane planting on areas of natural or semi-natural vegetation.

The analysis showed that sugarcane cultivation for ethanol production could expand to between 37.5 million and 116 million hectares under the three scenarios and that sugarcane ethanol could supply the equivalent of between 3.63 million and 12.77 million barrels of oil per day in 2045 given the projected climate change, while at the same time ensuring conservation of forests and areas reserved for food production. As a result, it would be possible to reduce oil consumption by 3.8%-13.7% and net global emissions of CO2 by 1.5%-5.6% by 2045 compared with data for 2014.

“Our findings show it’s possible to reconcile the two key goals to which Brazil committed as part of the Paris accord: conservation of natural environments, especially the Amazon, and increasing use of renewable energy,” said Marcos Buckeridge, a professor at IB-USP and one of the authors of the article.

The Brazilian component of the research behind the article was part of a project supported by FAPESP and by the National Institute of Science and Technology for Bioethanol (INCT Bioethanol). The participating researchers are affiliated with the University of Campinas’s Agricultural Engineering School (FEAGRI-UNICAMP) and the University of São Paulo’s Bioscience Institute (IB-USP) and Luiz de Queiroz College of Agriculture (ESALQ-USP).

“The study highlights Brazil’s courage in inventing sugarcane ethanol as a biofuel and implementing it as a nationwide solution,” Buckeridge told Brazilian reporters. “This potential expansion of sugarcane wouldn’t work without integration between the agricultural and industrial segments, and this in turn underscores the importance of concentrating strongly on the science and technology of sugarcane in the coming years. We must complete the job we began, which means second-generation ethanol.”

The report comes as a significant boost for Brazil’s decades-old ethanol industry, beginning with the Proalcoolprogramme starting up in the 1970s as an import substation tool. Since then the industry has undergone periods of crippling volatility – largely linked to ill-designed government fuel pricing policies seeking to ease the plight of indebted national oil company Petrobras, or to control Brazil’s periodic bouts of runaway price inflation.

Despite all the political and commercial mismanagement, scientists and planners have pushed forward the strategic goals of Brazil’s bioenergy industry. This now occupies centre stage in the energy-renewable ‘bioeconomy’ and its links to industrial innovation and sustainable development.

For instance, renewables  already account for 40% of the energy balance in the most advanced Scandinavian countries. In Brazil too, the share is 41%. The main renewable is sugarcane, which meets 17.2% of the demand (the rest is hydro). Almost 9% of the electricity generated in Brazil comes from biomass burning today.

Bioenergy has evolved as a multidisciplinary field of study for academics and researchers of all stripes – and from many nations. Their annual gathering is the Brazilian BioEnergy Science & Technology Conference (BBEST), This October it was  held in Campos de Jordão, near São Paulo.

The event was organized under the aegis of the Bioenergy Research Program (BIOEN), which is the channel for investment in research and innovation by FAPESP. São Paulo state, as the heart of Brazil’s sugarcane industry, is at the forefront of developments. The genome  sequencing of  sugar cane, genetic modification to enhance yield, and adaptation of ethanol fuel for aviation are all projects undertaken  with support from São Paulo state.