In Brazil, increasing the production of natural gas and limiting future bioenergy production by half could preserve as much as 12.6 MHa of forests
Although it has been demonstrated the advantages of bioenergy over fossil fuels for GHG emissions reduction, the issue of the indirect land use changes (ILUC) still remains. ILUC is an unintended consequence of bioenergy production. It occurs when farmers decide to switch land from food or animal production to energy crops. As the demand for food remains, these food crops face the need to move to new lands, mostly on the forests frontier, causing the release of high quantities of carbon to the atmosphere. Increasing the production of natural gas (NG) and limiting future bioenergy production could save forest areas in Brazil (especially in the Cerrado and Amazon regions). This is one of the conclusions of a study done by Professor Ivan Garcia-Kerdan, of the Sustainable Gas Institute (SGI) and Department of Chemical Engineering of the Imperial College London, in conjunction with several colleagues. The results were presented during the III Sustainable Gas Research Innovation (SGRI) conference, in September 25 and 26, in São Paulo. “Brazil is one of the world’s biggest producers of bioenergy and it has large amounts of petroleum and natural gas reserves. We study the dynamics of the energy and agricultural sector and the competition between bioenergy and natural gas resources in the country, along with the consequences involved,” he explained. Garcia-Kerdan says that most of the current energy system models (ESM) neglect the implications of the technological transitions operating in agriculture when accounting for greenhouse gas (GHG) emissions, worldwide.
“On a global scale, the share of direct energy consumption of the agricultural sector is 3% to 5%. The emission rates of greenhouse gases directly connected to the sector are also low: 1% to 2% of the world’s total. However, if you take into consideration the demand for agrochemicals and the changes in land use arising from the expansion of bioenergy crops, as well as the increasing need for food production, agriculture is indirectly responsible for as much as 30% of the global GHG emissions,” Kerdan stated.
He and other researchers of the Imperial College have developed a tool called the Agriculture and Land Use Sector Simulation Module (Ag&LU-SM). It is integrated with the ModUlar energy systems Simulation Environment (MUSE), which was also created by the Sustainable Gas Institute (SGI) at Imperial College team. Using Brazil as a case study, they worked with two hypothetical scenarios: the first explores a ten-fold expansion in the production of bioenergy by 2050, which means a 6% annual growth rate. The second scenario explores the expansion of natural gas production and a 50% reduction of the bioenergy production (that is, an annual growth rate of 3%).“The results of the simulations show that the development of balanced markets for bioenergy and natural gas could help limit the expansion of energy crops, thus preserving up to 12.6 million hectares of forest lands by 2050, bringing significant benefits in terms of emissions due to the capacity of forests to act as carbon sinks; nevertheless, we have to be very careful with expanding the natural gas infrastructure, as the carbon benefits from preserving forest lands could be easily off-set by the release of methane throughout the NG supply chain” Garcia-Kerdan explained.
The scientist also states that Brazil’s domestic natural gas market it is expected to grow at an average annual rate of 1.9%, from 2015 to 2030, and 0.7%, from 2030 to 2050. From a regional standpoint, the model shows that the Southeast region will continue to be the biggest consumer of NG up to 2050, arriving at 506 picojoules/year (1 joule is equal to 1011 PJ). However, it is the Northern region that will experience the greatest total percentage increase (155%), followed by the Midwest (70%), Northeast (69%), South (66%), and Southeast (42%).
In terms of land use, the results show that the Midwest region, and more specifically the Cerrado biome, should experience the greatest dynamics regarding changes in land use and an increase in new bioenergy crops (mostly sugarcane). Nevertheless, the Southeast will continue to be the Nation’s biggest producer of sugarcane and bioelectricity.