Manuel, Porcar, project coordinator

Aras de Los Olmos will be the first Spanish municipality to be supplied solely with renewable energy, thanks to the upcoming construction of a biogas plant with optimized bacteria. The initiative is part of the MICRO4BIOGAS project, financed with European funds and coordinated by the University of Valencia.

The Valencian town of Aras de los Olmos, where 380 inhabitants reside, will be the protagonist of a pioneering trial in the production of renewable energy, thanks to the construction of a 925.15 m³ biogas plant with bacteria optimized for the biodigestion of waste.

The construction of the plant is co-financed by the Ministry for the Ecological Transition and the Demographic Challenge and by the General Directorate of the Ecological Transition of the Generalitat Valenciana. The scientific strategy will be implemented by MICRO4BIOGAS, a research project led by the University of Valencia and endowed with 5.7 million euros from the European Commission.

The European consortium brings together experts in microbiology and biotechnology from 14 institutions in 6 countries, including the Aras de los Olmos City Council, and is coordinated by biologist Manuel Porcar from the Institute of Integrative Systems Biology (I²SysBio), a mixed center of the Universitat de València and the CSIC, in the Scientific Park of the academic institution.

Aras de los Olmos will be the first town in Spain to be self-sufficient only with renewable energy. The new biogas plant, whose construction is projected for the 2021-2022 period, is the final element in the town's 100% renewable self-consumption plan. This plan is based, above all, on photovoltaic and wind energy, but includes hydraulic and biogas/biomass as necessary complements to guarantee supply in periods without sun or wind.

"This part of the project also allows solving the problem that livestock farmers have with the management of slurry, to comply with the regulations of the European Commission," says the mayor of Aras de los Olmos, Rafael Giménez. «In turn, after completing the biogas production process, the waste can be reused as agroecological fertilizer and the water left over from the process will be used for irrigation. For all these reasons, this project can be considered a benchmark for the circular economy. »

Decomposer microbes

The research staff of the MICRO4BIOGAS project will work for four years to optimize the biogas production process. This product is a combination of methane with small amounts of carbon dioxide and traces of other gases, which is produced thanks to the anaerobic decomposition of organic matter, carried out by bacteria.

Biogas is burned, like biomass, to generate electricity or heat without adding fossil fuels to the carbon cycle. Furthermore, the organic matter that is decomposed to produce it can come from different sources, such as manure or food waste. In Aras de los Olmos, it will be mainly livestock waste.

Although all the stages of biodigestion are known, currently this process is a kind of 'black box' for science, since the complicated interactions of biochemical reactions that generate the gas have not been studied in detail. Scientists will thoroughly analyze the reactions to design bacterial communities—composed of natural microbes and microbes optimized with synthetic biology techniques—that ferment organic matter very efficiently. The objective is to improve the quality and production rate of gas.

 “Aras de los Olmos is an extraordinary example, both for being an initiative with a social and environmental basis and for being a privileged test bed for a project that aims, on the one hand, to optimize the production of biogas, and on the other hand also to democratize it, making it accessible to everyone,” says Manuel Porcar, responsible for the project.