Meg Cichon and Jennifer Runyon, RenewableEnergyWorld.com
December 11, 2012 | 2 Comments
Best Biomass Project: Nacogdoches Generating Facility, owned by Southern Co. in Nacogdoches County, Texas
The 100 MW Nacogdoches Generating Facility is a full-scale biomass plant in Nacogdoches County, Texas. The nation’s largest biomass plant supplies all of its power to Austin Energy in a 20-year PPA. The Austin City Council approved the $2.3 billion project in 2008, and the plant was commissioned in June 2012.
The entire facility utilizes just one boiler, making it the largest biomass bubbling fluidized bed (BFB) boiler unit in the world. The Nacogdoches biomass plant is also unique because it uses 100 percent non-merchantable wood fuel, which consists of forest residue from the surrounding areas, wood processing residues and clean municipal wood waste. Approximately 1 million tons of fuel will be required annually, which is to be procured within a 75-mile radius of the project site.
During construction, extreme drought put the water supply for the facility, the Angelina River, in jeopardy – the river became completely dry and was deemed unreliable to supply the facility. Developers constructed a 10-mile water line to a nearby lake that now provides ample water to supply plant operations.
Nacogdoches has made a significant impact in the surrounding towns. During construction, more than 100 vendor contracts for services and maintenance were established, as well as 25 fuel supply contracts. The facility allowed for more than 1,000 construction jobs, which was a boost for the local economy in the 200-resident town of Sacul. The facility is also set to employ 40 full-time workers. To train these employees, Southern Power and a fuel supplier sponsored a charity auction that contributed $21,000 to the Nacogdoches Technical Training Center. The facility will also contribute an estimated $58 million in new taxes over the next 20 years.
Best Bioenergy Project Runner-Up: Nocton Fen Farm, developed by Cummins Power Generation in the United Kingdom
Bardney, Lincolshire, United Kingdom is considered picturesque British countryside. So when developers proposed an anaerobic digester facility be built in the rolling hills of Bardney in 2010, there was some concern. But two years later, one would never know that the facility is already generating energy at first glance.
Funded in part by government grants, the 2 MW Nocton Fen Farm was built as part of an energy center in Bardney. An anaerobic digester, it generates heat and electricity with waste from local facilities including animal and crop waste from farms, brewery waste, and other mixed materials.
The digestion process uses these materials to produce biogas, which consists of mainly methane and carbon dioxide that is then converted to electricity and heat. Surplus electricity will be fed back into the National Grid, and leftover waste will be used locally as fertilizer. The facility also allows for landfill control in the community and boosts clean energy production that flows into the grid.
To appease the environmental and scenery concerns, the land where the facility lies was lowered, and the extracted soil was used to create bunding (similar to a wall) around the entire site, which minimizes the digester’s appearance on the local landscape. In order to achieve this, the ground level was reduced below sea level by approximately 5 meters through the removal of topsoil, subsoil and several meters of gravel and sand. This material was then used to provide a bund around the whole site, which was further landscaped to resemble the surrounding countryside.
The site was also constructed away from towns or villages and has absolute minimal affect on any local who live near the site, which is limited to about six houses in total – the nearest resident is more than 1 KM away.
Lead image: Envelope via Shutterstock