Biomass (open-loop and closed-loop)

Using biomass, together with fossil fuels, in our existing fleet is one of the quickest and most efficient ways to reduce carbon intensity. Using renewable biomass, such as chipped wood, to produce electricity helps reduce the net carbon footprint of power production.

NRG recently launched a pilot project at the Big Cajun II plant in New Roads, Louisiana to evaluate local conditions for growing dedicated energy crops near the site (closed-loop biomass). NRG has created a test farm on 20 acres of land at the plant site, which will be managed by a local farmer. Harvested into bales like hay, energy grasses are dried and shredded before being fed into the combustion chamber. Since the carbon emitted from the grasses was previously absorbed from the atmosphere during the growing season, combusting the above-ground biomass is nearly carbon neutral. When the extensive root systems of perennial grasses are considered, power from biomass may even be considered carbon negative.

NRG is developing open-loop biomass at our Montville plant in Uncasville , Connecticut . The project will convert an 82 MW peaking unit that currently uses heavy fuel oil and natural gas to a 40 MW green wood fueled unit. Organic plant matter such as forestry residues, tree trimmings and clean, recycled wood are obtained from multiple suppliers within a 100-mile radius of the Montville Station. The project is due online in mid-2011. NRG also is exploring other opportunities to use biomass throughout its fleet of generating stations.