By Fernando Colautti
It does not imply generating energy by incinerating waste, as the controversial Innviron proposed for Capital and Villa María, in an adventure that ended in scandal years ago. Burning garbage is the method most questioned from an environmental perspective.
To produce biogas, organic waste is recycled and transformed into a resource. Thus, a large part of the garbage does not need to be buried occupying space, with the risk of contamination. And at the same time, the methane gas generated, instead of being released into the air, affecting the environment, is used as a source of energy. There is no incineration, but natural decomposition.
For now, it doesn't seem that simple or a brilliant deal. But it is an alternative and possible path that two towns in the south of Córdoba are encouraged to travel. The greatest experience advances in Huinca Renancó. Another, more limited and artisan, is tested in Coronel Baigorria.
In both, the energy they will generate in this way would be equivalent to that required by their public lighting services. In principle, they were imagined with that destination.
The Cooperativa Eléctrica de Huinca Renancó (CEHR), in partnership with the Federation of Federated Cooperatives (Fecofe), designed a plant that could process the organic waste generated by some 20 thousand inhabitants of this region. A few months ago, the Province set up a regional landfill that receives waste from eight towns in the General Roca department, in the south of Córdoba. The inorganics are already separated to be sold and the organic ones will go to the biodigesters to generate energy.
The biogas plant, started in 2013, was expected to be inaugurated at the end of 2014. Now, they are talking about the first months of 2016.
Juan Rivotta, manager of the local cooperative, pointed out that there are delays due to obstacles in the entry of imported equipment (the technology is Italian) and for economic reasons. Waste separating equipment recently arrived from Italy and the arrival of two generating groups from Costa Rica is awaited.
The project was born with the support of the Ministry of Agriculture of the Nation, which contributed 18 million pesos, already invested. "We will need about three million more, which we are managing with the Environment of the Nation," said Rivotta.
With 21 million, it will already be possible to open, although with two of the five expected generated. For the other three, it will require additional investment, at a later stage. "Once generating, you could look for credits," said Rivotta.
The final idea is to generate one megawatt per month with methane gas. With two engines, they will reach 40 percent.
To compare: Huinca Renancó consumes up to seven megawatts / month in winter. In other months, it is around five, so the plant would produce (with five generators) up to 20 percent of the total demand of the city, of 10,000 inhabitants. It would represent more than what all your street lighting needs.
Rivotta clarified that the energy from the biodigesters would not be used directly in the locality: the Wholesale Electricity Market will buy this contribution, for the national grid, through an agreement with Energía de la Nación. "It would be more complex and less profitable if it were used directly in the town," said the manager of the cooperative.
For the development of the project, the Montanaro-Ifes companies were contracted. The municipality endorses it and provides the land, while the regional delegation of Inta adds its advice.
The biodigesters will need a minimum of biomass that the garbage of the eight towns will not be able to contribute. For this reason, the addition of forage sorghum has already been defined, which the cooperative itself will plant in? A 70-hectare field, or which it will buy from producers in the area.
The process will leave a residue, which is not such either, because it is useful as a fertilizer. Its real market remains to be seen, but at least it will be useful for fertilizing the soils of the green spaces in the region.
Rivotta clarified at the outset: the main advantage is not the business of generating energy, but the environmental contribution by reducing waste, without impact.
“It is not a big business, at least with the current numbers. If it were not with subsidies, the project would be totally unviable for this cooperative and this town, due to the investment required ”, said the cooperative manager.
"Environmentally it is good, and incidentally it will be a source of resources, although the economic equation will have to be evaluated over time, according to the prices of the electricity market for alternative energies," he added.
Rivotta himself admitted that, due to the volume of waste available, biogas would be more efficient to process waste from large cities. "Bringing them here from other areas does not close, due to the high cost of freight," he said.