The United Nations’ Clean Development Mechanism (CDM) agency has approved an application by Brazil utility CPFL Energia to sell carbon emissions credits from the repowering of six small hydroelectric projects.
The Executive Board of the U.N. Framework Convention on Climate Change issued a registration August 22 for six projects in Brazil’s Sao Paulo State that annually will offset 31,190 metric tons of carbon emissions that otherwise would be produced by fossil fuel-fired power plants.
All the repowering projects create additional capacity and generation by replacement of original equipment installed between 1910 and 1930, when generation efficiency was about 65 percent. Installation of new turbine-generators results in efficiencies exceeding 80 percent with no changes in water use.
ï¿½All repowering projects were limited to tapping additional power without any modifications to the sites other than basically replacing old turbo-generators by more efficient ones, reinforcing foundations, and, in some cases, by increasing the capacity of the water adduction channels,ï¿½ project documents said.
Work has been completed on three of the projects and still is to be carried out on the other three. When complete, the total capacity will increase to 35.6 MW from 25.6 MW and generation will increase by 866 GWh annually.
Projects, new capacities, rivers, and capacity increases are:
o 5.04-MW Esmeril, Esmeril River, 3.3 MW;
o 10.8-MW Dourados, Sapucai River, 4.4 MW;
o 8.05-MW Sao Joaquim, Sapucai Mirim River, 2.5 MW;
o 4.8-MW Gaviao Peixoto, Jacare-Guacu River, 700 kW;
o 2.71-MW Chibarro, Chibarro River, 400 kW; and
o 4.2-MW Capao Preto, Conxim, Negros, Itauna, and Quilombos rivers, -1.3 MW.
Although Capao Preto will experience a decrease in installed capacity, the junction of its penstocks will be revised to reduce head losses.
CPFL Energia applied for the carbon reductions credits with C-Trade Comercializadora de Carbono Ltda., a consulting company that identifies, certifies, and negotiates carbon credits.