Honeywell announced a $35-million renewable energy project for the city of Wilmington, Del., which will feature a first-of-its-kind facility that converts two sources of biogas into power and heat for the city’s wastewater treatment plant.
The project is part of a city-wide initiative to decrease energy costs and greenhouse gas emissions, a program that has also included Honeywell-led solar installations and energy-efficient building improvements. Combined, the upgrades will help the city trim its carbon footprint by approximately 35% and meet nearly 50% of its electricity needs with renewable energy.
The efforts are also helping produce and sustain local jobs. Honeywell plans to use Wilmington-area contractors and union labor to support the latest work, providing more than 100 jobs during construction and creating up to five permanent positions.
The centerpiece of the new project is the construction of a Renewable Energy Biosolids Facility to harvest and harness naturally occurring biogas, supplying a renewable resource to not only generate electricity for the Hay Road Wastewater Treatment Plant, but provide thermal drying to greatly reduce the volume of sewage sludge the city pays to remove.
The biosolids facility will capture methane produced by anaerobic digesters at the Hay Road plant, a potential energy source that is currently flared off. The gas will mix with additional methane from the nearby Cherry Island Landfill, which is operated by the Delaware Solid Waste Authority. And the blend will be purified at the facility and used to power reciprocating engines that can generate up to 4 megawatts of electricity, enough energy to provide up to 90% of the treatment plant’s power.
The biosolids, or sewage sludge, that come out of the digesters will also be dehydrated by heat recovered from the engines. This thermal drying process is expected to reduce the amount of sludge the city needs to truck away by approximately 75%—from 140 to 35 tons per day—greatly reducing material-handling costs.
The biosolids facility is also projected to trim greenhouse gas emissions by 15,700 metric tons annually. According to figures from the U.S. Environmental Protection Agency, the decrease is equivalent to removing more than 3,000 cars from the road.
Construction of the Renewable Energy Biosolids Facility is expected to begin in spring of 2013 and the building will be commissioned in summer of 2014. Honeywell is collaborating with engineering firm CH2M HILL to design the project. The company will also provide operations and maintenance support for the facility through an annual service agreement.
This is the second phase of the city’s sustainable energy initiative, building on previous work performed by Honeywell that includes the installation of photovoltaic solar arrays at the Wilmington water filtration plant and municipal complex, conversion of all traffic lights to high-efficiency light-emitting diodes, and the installation of ultra-efficient lighting, heating and air-conditioning equipment in city-owned properties. To date, the project has generated more than
$1 million in energy cost savings, and $590,000 in rebates and renewable energy credit revenue.