By Mario Osava FOZ DO IGUAÇU, Brazil, Mar 18 2020 (IPS)
“It used to be complicated, I would have lunch with the flies,” recalls Pedro Colombari, laughing, on his 400-hectare farm where he fattens 5,000 pigs and raises 400 cattle outside of a small town in southern Brazil.
Biogas production keeps disease-carrying insects away by extracting the gases from animal waste through anaerobic biodigestion by bacteria. The settling ponds for the manure, which “produced 99 percent of the flies,” have disappeared, according to Colombari.
Using the biogas, the farmer generates electricity shared with neighbouring properties in a micro-grid set up in the municipality of São Miguel do Iguaçu, 42 km from Foz do Iguaçu on Brazil’s border with Argentina and Paraguay.
For fellow farmer Ademir Escher, the biggest benefit was the reduction of “70 to 80 percent of the stench” from the manure he uses to fertilise his hay crop.
Since last July, the waste from the 1,200 pigs he fattens on his three-hectare farm has been producing biogas for the mini power plant in Entre Rios, 133 km from Foz do Iguaçu.
Escher is one of 18 pig farmers who supply the fuel that produces the energy for almost all of the local government’s offices and services in the municipality of 4,600 inhabitants.
The mini power plant, with an installed capacity of 480 kilowatts, was created as part of programmes implemented by the Itaipu Binational Hydroelectric Power Plant, which promotes alternative energy sources in its area of influence as well as technological innovations, such as electric or biomethane powered vehicles, or purified biogas.
Itaipu, the second largest hydropower plant in the world, shared by Brazil and Paraguay, has an installed capacity of 14,000 megawatts.
That is equivalent to 29,166 mini power plants like the one in Entre Ríos.
But the binational giant, which accounts for about 11 percent of Brazil’s energy consumption and 88 percent of Paraguay’s, continues to promote biogas production, to generate both electricity and biomethane.
The use of livestock manure and organic waste to produce energy and biofertiliser reduces the sediment that runs into the rivers and pollutes the dam’s reservoir, explained General Luiz Felipe Carbonell, Itaipu’s coordination director.
All sediments affect water quality, which is “critical to power generation,” he said. But organic sediments are especially harmful, because they fuel the proliferation of aquatic fauna that damage the plant’s machinery and the dam, he said.