Greater New Haven Water Pollution Control Authority

GNHWPCA To Use New Energy System

Electricity costs are on the rise throughout the Greater New Haven region. This is no surprise to any home owner or apartment dweller as they’ve opened their electric bill in the past six months. A lack of adequate transmission facilities coupled with supply de-regulation throughout the state has caused rates to skyrocket with no end in sight.

In an effort to minimize future rate increases, the Authority issued a Request for Proposals for the beneficial use of thermal energy from the exhaust gases currently discharged by the sludge burning incinerator at the East Shore Treatment Facility.

Vendors were required to use the thermal energy produced on site and propose either a reduction in plant operation costs or a new revenue source for the Authority, or a combination of both to reclaim the maximum value for thermal energy. The value could be realized through the potential generation of electric power, cost reductions for natural gas, incentive payments for environmental benefits, or the use of any additional thermal capacity.

In 2007, the Authority entered into an agreement with the Dresser Rand Company to pursue the opportunity to design, construct, and maintain a multiple hearth energy recovery system. The Dresser Rand proposal consists of a waste heat boiler system which will capture the exhaust gases from the sludge burning incinerator and create high pressure steam which will turn a turbine generator to produce electricity. All of the power produced is used internally at the plant. In addition to reducing our operating costs, this would allow for the East Shore Treatment Facility to be more self sustaining in the event of a major power loss from the connecting grid.

It is estimated that 4.4 million kilowatt hours of electricity will be produced per year at an initial capital cost of $5.5 million. The project will receive a one- time capital grant from the State of Connecticut, as well as revenues from the sale of renewable energy credits. We will also realize a $1.8 million savings in transportation costs for natural gas used in the sludge burning incinerator. Over the next 25 years, this project will achieve a net positive cash flow of more than $24 million, and help to reduce our dependence on electricity.