According to preliminary results of a study carried out by the National Institute of Agricultural Technology (INTA) together with private consultants, the generation of biogas achieved an average reduction of 98.5% of greenhouse gases, compared to power generation as standard (from fossil fuels). The calculation of energy emissions was made based on the methodology of the European Renewable Energy Directive RED II.
The study, carried out by Jorge Hilbert, Jonatan Manosalva and Karen Poniemann from INTA’s Institute of Rural Engineering, together with private consultants Ariana Camardelli and Patricio Geretto, focused on an analysis of emissions in the production of bioelectricity and heat, from biogas, in the Bio 4 Bioelectric complex (BG1, BG2 and CGY), which form a complex with a total power of 6 megawatts.
The plants are integrated into the corn starch bioethanol BIO4 biorefinery, located in the province of Córdoba, and receive manure from a feedlot, added to waste from the dairy industry and recovered cooking oil. In addition, they inject electricity into the Argentine interconnected system, through a 20-year contract with CAMESSA.
“In order to strengthen the benefits of this technology, these types of studies are carried out evaluating the capacity to reduce greenhouse gas emissions that are achieved in comparison to the fossil alternative,” said Jorge Hilbert, a researcher at the Rural Engineering Institute and a benchmark for INTA on the subject.
Among the objectives of the biogas industry is the reduction of the consumption of fossil fuels, with the ultimate goal of mitigating global warming and, in addition, providing fertilizers and eventually also capturing carbon in the soil. “If the entire cycle is achieved, negative emissions could be achieved, that is, a fuel that captures carbon instead of emitting,” Hilbert said.
The total annual production of the complex reached 24,137,469 m3 of biogas, 57,202 MWh of electricity injected into the national grid and 26,316 MWh as thermal energy used in the biorefinery. A total of 320,000 m3 of digestate was produced and it is used in fertigation and part of it is reinjected in the biorefinery.
“An emission of between 1.04 and 1.14 gCO2/MJ was obtained,” indicated Hilbert, who explained that “if a comparison is made between the generation of energy in a standard way (from fossil gas) and the generation of energy from biogas, an average reduction of 98.5% was achieved, very close to the carbon-neutrality so sought after in today’s world.”
In this line, Hilbert assured that “if the production of thermal energy is compared, the reduction was more than 98%, very close to carbon neutrality.” In addition, “the emissions associated with the digestate, which consider transport, application and fertilization, reached 1.57 kgCO2eq/m3,” he pointed out.
“These results open up a huge panorama of development for all types of energy that are produced in biogas plants such as bioelectricity, biomethane and heat,” said the INTA specialist, who assured that “INTA will continue to work together with the company in order to further improve these results to achieve a biofuel and bioelectricity that have a negative emission.”