New Sustainable Energy Project at Wilmington's Wastewater Treatment Plant Will Save City Millions of Dollars in Energy and Disposal Costs, Create Over 100 New Jobs, and Provide a More Sustainable Method of Managing Biosolids

Posted on  06/10/2012 8:30 pm

After months of study and public presentations of the plan, Wilmington Mayor James M. Baker and Public Works Commissioner Kash Srinivasan say the City should move forward with the second phase of a groundbreaking, sustainable energy initiative that further illustrates the City’s commitment to finding sustainable solutions to environmental challenges while at the same time creating new jobs and saving over $1 million per year in energy costs.

The new phase of Wilmington’s Sustainable Energy Initiative is the construction of the Renewable Energy Biosolids Facility—an energy plant that will convert renewable fuel into electricity and heat at the City’s Hay Road Wastewater Treatment Plant (WTP). The energy plant is the second phase of the City’s $50.5 million Sustainable Energy Initiative. When completed, the Renewable Energy Biosolids Facility will consist of two parts, which include:

  • Capturing the methane gas generated by digesters at the plant and combining it with methane gas produced by the adjacent Cherry Island Landfill to provide a renewable, self-perpetuating fuel source for a cogeneration system that will power the plant instead of relying upon more costly electricity purchased from a power utility.
  • Employing thermal drying technology using the excess heat from electricity generation to greatly reduce the volume of biosolids or sludge produced by the plant (biosolids are the naturally occurring byproduct of treating wastewater).

The City’s sustainable energy initiative is being implemented under the State’s Energy Performance Contracting Act, an innovative performance-based procurement method and financial mechanism whereby energy and operational savings that result from the installation of new building systems pay for the cost of the project through a Guaranteed Energy Performance Contract.

First presented to City Council and the public in late 2011, and first reported by the News Journal in January of 2012 following the issuance of a City news release and another public presentation to City Council by the Department of Public Works, the Renewable Energy Biosolids Facility was discussed most recently with members of City Council in briefing sessions in April and May. The project will receive another public examination on June 18 at a City Council Finance Committee hearing and on June 19 at a meeting of the City Planning Commission. Mayor Baker said he is hopeful that City Council could take a final vote on the project at either its June 21 or July 5 meeting.

The City’s Wastewater Treatment Plant on Hay Road is a major source of greenhouse gas emissions due to continuous methane flaring (the burning of the methane gas that is a naturally occurring byproduct of the wastewater treatment process), the use of “grid” electricity, and the off-site hauling of biosolids to out-of-state facilities for use or disposal. This new project phase is projected to reduce greenhouse gas emissions by 15,700 metric tons per year, the equivalent of greenhouse gas emissions from 3,078 cars or 36,512 barrels of oil. Combined with Phase I of the Sustainable Energy Initiative, the new energy plant will help the City reduce its greenhouse gas footprint by 35%.

Mayor Baker and Commissioner Srinivasan said the current practices at the plant expose the City to financial risks associated with rising future electricity and biosolids disposal costs. They said the thermal drying process will reduce the amount of biosolids produced from 140 to 35 tons per day; in addition, the product created by the drying process will be a marketable end product suitable for use as fertilizer or fuel. They further noted that reducing biosolids to a more manageable and marketable product greatly reduces environmental impacts and regulatory risks.

When the Renewable Energy Biosolids Facility is completed by early 2014, Wilmington will join several other major cities in the mid-Atlantic region that have switched from the land application of biosolids to thermal drying, including Philadelphia, Washington, D.C., and Baltimore. This phase of Wilmington’s Sustainable Energy Initiative will enable the Hay Road Plant to operate on “green” energy at a projected average annual net cost savings of $800,000.

The Renewable Energy Biosolids Facility will be built by local contractors and union labor. Over 100 construction and five permanent jobs will be created. Prime subcontracts will have a minimum 15% minority business enterprise requirement.

The City will finance the estimated $36 million project through the sale of municipal bonds. Under the City’s Guaranteed Energy Performance Contract, annual savings to the City are guaranteed to exceed public financing and other project-related costs.

“The green improvements at the Hay Road Plant represent another significant step towards building a more sustainable future for Wilmington residents,” said Mayor Baker. “New Castle County residents, who send waste to the City’s plant and help to subsidize its operation, will also see a savings from this project. When combined with work we’ve already completed among other city-owned properties, Wilmington continues to achieve many financial and environmental benefits. This project will produce dividends for the citizens of Wilmington and New Castle County for many years to come.”

The Renewable Energy Biosolids Facility at the Hay Road WTP represents just a portion of the City’s overall green energy program. The $14.5 million Phase I of the Sustainable Energy initiative included construction of a booster pumping station at the Porter Plant to decrease operating costs; installing arrays of photovoltaic cells at the Porter Filtration Plant and the Turner Municipal Complex; the conversion of all City traffic lights to high-efficiency light-emitting diodes (LEDs); and the installation of energy efficient lighting and HVAC equipment in City-owned properties. To date the project has generated over $1 million in energy cost savings and $590,000 in rebates and renewable energy credit revenue.

When completed, Phase I and Phase II will replace over 50% of the City’s grid electricity consumption with renewable electric generation, as well as easily surpass the 20% greenhouse gas reduction goal adopted by the city under the Climate Protection Agreement.

When combined, both phases of the project will produce an annual average cost savings of about $1.5 million over the term of the 20-year project.

Wilmington’s Greening Initiatives

The City of Wilmington has demonstrated its commitment to the environment by introducing the state’s first single-stream, curbside recycling program. The city was also among the first cities in the United States to join as a Founding Reporter of The Climate Registry, a nonprofit organization established to measure and publicly report greenhouse gas emissions in a common, accurate, and transparent manner that is consistent across industry sectors and borders. Mayor Baker issued an executive order in August of 2008 outlining steps the City government is taking to lessen the impact of global warming on Wilmington and help preserve a respectable quality of life for City residents.

One of the primary goals of Wilmington’s new sustainability initiative is to achieve a meaningful reduction in its energy footprint and reduce greenhouse gas emissions. While City actions alone are too small to impact global greenhouse gas emissions trends, the City is part of coalitions across the country that collectively can make a difference.

Honeywell, Wilmington’s Energy Services Company

Honeywell is a global leader in energy services, working with organizations to conserve energy, optimize building operations and leverage renewable energy. Since the 1980s, Honeywell has completed more than 5,000 energy-efficiency projects in facilities across the globe. It also helped 5 million homeowners decrease their energy use through its work with utilities. Overall, more than 50 percent of Honeywell’s portfolio is dedicated to technologies and services that reduce energy use and emissions. The company estimates the U.S. could reduce energy consumption 15 to 20 percent by immediately and comprehensively adopting its existing technologies.