The air smells sweeter in Chile – or at least in the small town of Pichidegua – because MTU Onsite Energy in cooperation with the distributor Detroit Chile has built a modular CHP plant there. It produces electricity for the local residents. It's a landmark in the long, thin South American country that seems predestined for localized energy generation because of its unique geography. One pleasant side-effect of the CHP plant is that the pig slurry no longer smells to high heaven because it is fermented into biogas.
We are on our way south from the capital Santiago. After three hours, we reach Pichidegua, a small town in central Chile with a population of around 18,000. Near here, there are seven pig farms run by the company MaxAgro. On a narrow country road we are looking for the entrance to one of them, Las Pampas, but drive past the gate several times before we spot it. Nothing indicates that thousands of animals are kept here, only a few meters away behind a maize field – no smell, no flies …
That is surprising to say the least, because in 2012 protests by local people living close to a pig-rearing and slaughtering plant in northern Chile with 450,000 animals made big headlines. The parent company Agrosuper S.A. – one of the country's biggest meat producers with an annual turnover of U.S. $ 1.1billion and around 15,000 employees – eventually had to close down the plant. The reason? Because the local population protested vociferously against the foul smell of the pigs and the swarms of flies. The Chilean government labeled the processes a "sanitary disaster."
Chile's first biogas plant
MaxAgro rears 130,000 pigs in its plants, which have also had their share of headlines over the past year – though in their case not because of protesting locals. The company is the first business in Chile to install a biogas plant and now generates energy from pig slurry. “We wanted to find an eco-friendly and profitable solution for the production of pork,” recounts CEO Cristián Kühlenthal. “We installed digesters to limit the smell problem as long ago as 2008, but we only used the waste as fertilizer. A biogas plant from MTU Onsite Energy that we can use to generate energy from the gas produced is something entirely new for us,” explains Kühlenthal, adding, “Without environmentally friendly solutions, no business is viable in the long run nowadays.”
Annual energy output 6,400 MWh
As a pig-farming operation, MaxAgro got together with Genera Austral, a Chilean biogas plant operator, to develop a business model. They installed an MTU Onsite Energy CHP plant not only at the MaxAgro facility in Pichidegua but also in Santa Irene. They are both equipped with a Series 400 engine and produce 400 kW of electrical energy and 462 kW of heat. “The two plants together generate a total of 6,400 MWh of electricity a year that we feed into the national power grid,” relates Kühlenthal. The thermal energy recovered from the engine coolant and the exhaust is used to heat the pig pens in the winter. “The electricity we produce from the two plants is enough to supply around 2,500 families in the area,” Cristián Kühlenthal elucidates.
Maintenance by remote control
The system is looked after by Detroit Chile, the MTU Onsite Energy distributor in Chile. “We can monitor the technical parameters of the plant around the clock with a remote control system and so we can respond immediately if there are any irregularities,” explains Cristobal Orcos of Detroit Chile, emphasizing that his engineers have been specially trained for the job at MTU Onsite Energy in Augsburg.
Electricity from biomass
The principle of the plant is identical with that of numerous other biogas plants already installed in Europe – solid and liquid waste (slurry) from the pig pens is pumped into a digester housed underneath a dome-shaped roof. “We have nicknamed the dome the ‘concrete cow’ because inside it the process is the same as in a ruminant’s stomach,” jokes Matías Errázuriz, CEO of Genera Austral and operator of the plant. “It is hermetically sealed and all that comes out at the end of the process is the almost odorless residue that runs off into a tank and is used as organic fertilizer for the surrounding fields.”
The digester is seven meters deep with an area of 40 square meters and holds roughly 6,000 cubic meters of biomass. The biomass is mixed and fermented to produce biogas with a methanol content of between 50% and 60%. Before the gas is pumped to the engine, it is passed via underground pipes through an active carbon filter that reduces the sulfur content.
20% renewable energy by 2025
The opening of the new biogas plant in Las Pampas in November last year was attended by Chilean Environment Minister, María Ignacia Benítez, and Energy Minister, Jorge Bunster. Bunster underlined the massive potential of biogas as an energy source that could reach “up to 10,000 gigawatt-hours a year and source as much as 42% of its fuel from livestock farming.” Environment Minister Benítez,drew attention to the growing importance of sustainable energy generation and emphasized that the project developed by Genera Austral for MaxAgro was an “important part of meeting the targets of the 20/25 Act.” That legislation requires that the proportion of renewable energies within the overall energy mix must reach 20% by 2025.
“Our door is open to anyone”
At the official opening, Cristián Kühlenthal encouraged other businesses in the industry not only to invest in recycling their organic waste but also to take the extra step into energy generation. “Our door is open to anyone who would like to be convinced of the efficiency and sustainability of our projects on site,” says the MaxAgro CEO, who is also planning to convert the rest of his company’s pig farms in the same way. One of the most important factors for him is the reaction of the people living in the surrounding area. “As a busines we obviously want to make money, but at the same time we want to use technologies that meet the highest international standards – such as those in Germany – and to do so in cooperation with the people who live nearby. That requires a lot of work convincing people and breaking down prejudices,” Kühlenthal observes.
Localized energy production as opportunity
Stretching around 4,300 kilometers from north to south but having an average width of only about 200 kilometers, Chile is one of the most unusually shaped countries in the world. If placed elsewhere on the map, it would reach from Greenland to Morocco. That particular geography predestines the country to invest in the development of localized energy generation. In the past, Chile attempted to supply its growing energy needs from conventional thermal power plants and gigantic north-south cable lines. But some years ago the Chilean government had a rethink. The country is dependent on imported energy, the price of which is continually rising. In addition, the power grid is overloaded and the supply is unreliable. Localized solutions are an opportunity to solve the problem.
“The market is massive”
Over the next two years, Cristobal Orcos at Detroit Chile is expecting to see more MTU Onsite Energy biogas plants built in this part of South America. Genera Austral CEO, Matías Errázuriz, is also optimistic: “In Chile there is a massive market for generating energy from biogas – not only in the agricultural industry but also on landfill sites, in forestry and salmon farming, in the food industry and in the wholesale grocery trade.” But integrating new technologies in a country takes time. “When you think that there are roughly 7,800 biogas plants in Germany that produce a combined total of 3,400 MWh of electricity, there is still enormous potential in Chile because we have far more farms than the Germans,” he muses. Genera Austral has already drawn up an investment plan for building more plants of this type in the coming years. After all, doing so solves two problems at once: electricity and heat are produced locally by a clean process. And the waste from pigs, hens and cattle does not arouse the anger of local residents.