February 23, 2012

Brazil Co-ops Use Sugarcane Residue to Generate Electricity

One of the advantages of using sugarcane to produce sugar and ethanol is that the left over residue called bagaco can be used to produce electricity not only to run the sugar/ethanol mill itself, but also to sell back into the grid. Using sugarcane residue to generate electricity is a common practice in the sugar/ethanol mills of Brazil. In the state of Parana, 2% of the electricity generated in the state comes from the burning of sugarcane residue. In most of the cases, the electricity is cogenerated in association with the mill and not by a stand along generating facility.

The Cocamar Cooperative in Maringa, Parana decided to build a stand along electrical generator that uses primarily sugarcane residue. The plant, which opened in 2009, cost R$ 35 million to build and it has been generating a profit of R$ 5 million per year, which means it will pay for itself in seven years. The facility can generate 13 megawatts per hour which would be enough electricity to power a town of 70,000 inhabitants.

The principal customer of the facility is the cooperative itself and its various nearby industrial facilities. The cooperative estimates that it saved approximately R$ 13 million in 2011 by generating its own electricity instead of purchasing it from a third party. The cooperative monitors the cost of its own electricity compared to electricity from an outside source on a monthly basis and thus far since their facility opened, their own electricity has been cheaper than the electricity they could had purchased on the open market.

The Cocamar generating facility receives 700 tons of sugarcane residues per day. Using sugarcane residue offers a lot of advantages including: an inexpensive raw material, it is easy to transport and store, it's efficient in making electricity, and it's a renewable source of energy thus reducing greenhouse gas emissions. During the intra-harvest period when sugarcane is not being harvested (December-March), the plant can burn residues from eucalyptus processing, or crop residues from rice, soybeans or corn.

With the success of the Cocamar facility, various other cooperatives in the state are in the process of building pilot facilities that can use their own crop residues to generate electricity. Various educational organizations in the state have even joined together to create a MBA program in Bioenergy.