Coal, Emissions, Gas

City of Fort Worth, TXU turn waste into watts at wastewater treatment plant

FORT WORTH, Texas, March 20, 2002 — The City of Fort Worth’s Village Creek Wastewater Treatment Plant uses a combination of technologies to conserve electricity, generate power, reduce costs and use fuel and heat efficiently.

The city burns methane gas produced during an organic treatment process in two new combustion turbines to provide about half the electricity needed to operate the plant around the clock.

The City of Fort Worth and the Texas Water Development Board (TWDB) collaborated to finance and install the turbines. The entire project is expected to save the city an average of about $1 million a year over a 20-year period. TWDB provided a $9 million low-interest loan to finance the majority of the $10 million cost of purchasing the turbines and renovating the building that houses them.

TXU Energy Services, a subsidiary of global energy services company, TXU (NYSE:TXU), operates and maintains the twin 5.2-megawatt generators. TXU Energy Services will also seek additional biogas sources, decide the most cost effective way to operate the turbines and broker any surplus power back to the grid. Natural gas is another fuel source option for the turbines.

The cleaner burning turbine generators replace older, less-efficient internal combustion engines that had been in operation for 40 years and supplied about 30 percent of the plant’s electricity. The combustion turbines are located in an existing building at the wastewater treatment plant.

“This project makes sense for the city from both an environmental and business stand point.

Environmentally, the project allows us to have a positive impact on air quality in the region, which we all know is a prime concern. Plus, the city can use the air credits from this project as a future economic development tool. On the business side, the contract saves the city money. The water department would have had to hire additional employees and consultants if it had not privatized this part of its operation. Also, methane is a free fuel source for us, so it is wise to continue capturing and using it,” said Mike Groomer, Assistant City Manager. “These are the types of partnership initiatives government and private industry need to continue pursuing.”

Village Creek is one of the few wastewater treatment plants in the nation able to interconnect with a transmission system and sell power generated by combustion turbines back to the local electric service provider. Eventually, when power demand at the plant is at its lowest, the turbines may produce enough electricity to sell back into the electrical grid.

A heat recovery system captures high-temperature exhaust from the turbines to ensure a constant temperature (95-100 degrees F) for the waste treatment process. It will also be used to heat the plant’s administration building during the winter.

“Given TXU’s experience with distributed generation projects, we are uniquely qualified to manage on-site generation systems like the one at Village Creek,” said Dan Reiff, vice president, commercial and industrial, TXU Energy Services, a competitive subsidiary of TXU. “We’re pleased that we could partner with the City of Fort Worth to operate and maintain an efficient, environmentally clean energy source. The Village Creek project is representative of the many innovations that will emerge when the Texas electric market opens on Jan.1, 2002.”

TXU, which guarantees the turbines will operate 96 percent of the time, monitors the units from a remote control center in Dallas to ensure maximum performance. The City of Fort Worth’s contract with TXU is for 20 years with annual renewal required.

Village Creek Wastewater treatment plant, the city’s sole sewage treatment facility, is permitted to treat an average of 166-million gallons per day. All products of the wastewater process are reused. The water is released into the Trinity River and flows downstream, where it becomes a drinking water source for Huntsville, Houston and other communities. The methane is captured and converted into electricity and the biosolids are dewatered and applied to allowable agricultural land as fertilizer. The city contracts with Agronomic Management Group to operate the biosolids land application process.

TXU is a multinational provider of electric and natural gas services, merchant trading, energy marketing, telecommunications and other energy-related services. TXU is one of the largest energy services companies in the world with more than $25 billion in revenue and $43 billion in assets. TXU delivers or sells energy to 11 million customers primarily in the US, Europe and Australia. More information about TXU may be obtained from the TXU web site at