Ameresco Inc., a private renewable energy company, and the Philadelphia Water Department (PWD) announced an agreement to design, build and maintain an innovative wastewater biogas-to-energy facility expected to reduce PWD energy costs by over $12 million over the course of the 16-year contract.

The Northeast Water Pollution Control Plant (NEWPCP) Biogas Project will generate electricity and thermal energy for use on-site, fueled mainly by biogas from the NEWPCP digesters. The $47.5 million construction project is designed to generate 5.6 MW of power.

A natural byproduct of sewage treatment, biogas can be refined and utilized as a fuel for generators or equipment. Currently, half of the biogas generated from the wastewater treatment process is used to heat processes at the NEWPCP, while the other half is being flared, consuming energy and increasing local emissions. Ameresco says the biogas project will now be used as a ready source of renewable energy, which will not only save money, but also provide a secure source of green energy for NEWPCP.

The public-private partnership between the City of Philadelphia and Ameresco qualifies the project to obtain a grant made possible through the American Recovery and Reinvestment Act. Bank of America Merrill Lynch, through its Energy Services business unit, has agreed to provide the financing for this project.

Ameresco will manage engineering, procurement, construction, and maintenance on the project over the course of the contract. The project is expected to reduce carbon emissions by nearly 22,000 tons per year, which equates to the removal of 4,833 cars off the road or the planting of 5,390 acres of pine forest, according to Ameresco.

Ameresco partnered with the San Antonio Water System (SAWS) to open the Dos Rios Water Recycling Center in September 2010, the first sewage facility in the United States to refine biogas for the grid. Ameresco also developed another waste-to-energy solution for the Dallas Water Authority where both electricity and heat are utilized on site.