Skip to Main Content

Clean Water Services’ new cogeneration system turns waste to watts

Renewable energy generated from wastewater, food grease and solar meets 60 percent of local water resource recovery plant’s needs

Tigard, Ore. — May 4, 2016 — Clean Water Services, with Energy Trust of Oregon and the Oregon Department of Energy, dedicated today a new cogeneration system that converts wastewater and food grease into clean, renewable energy. With this innovative system, Clean Water Services Durham Treatment Facility is the third water resource recovery plant in Oregon co-digesting fats, oils and grease.

The new system triples Clean Water Services’ renewable energy generation, creating 60 percent of the electricity needed to run the water resource recovery facility when coupled with its existing 403-kilowatt solar electric system. The systems are expected to generate 12,800 megawatt hours of electricity per year — enough energy to avoid producing 6,000 tons of carbon dioxide annually. Renewable electricity and heat produced will be used onsite, reducing operating costs for Clean Water Services by nearly $800,000 annually, ensuring value for its ratepayers. Generating clean, renewable energy from biogas reduces greenhouse gas emissions and helps Oregon meet its carbon reduction goals.

“Clean Water Services is turning a liability into an asset by harnessing energy that was literally going down the drain and using it to generate clean power. That’s smart leadership and a cost-effective investment,” said Betsy Kauffman, renewable energy sector lead, Energy Trust.

Since 1993, Durham has operated a 500-kilowatt cogeneration system using biogas from treatment of the communities’ wastewater to help offset its own energy usage. By replacing this smaller engine with two new engines, Durham now has a 1.7-megawatt cogeneration system fueled by biogas produced from the anaerobic digestion of municipal wastewater solids as well as fats, oils and grease (FOG) from Washington County restaurants and other businesses. FOG, also known as “brown grease,” is pumped out of restaurant grease traps and interceptors at regular intervals.

“By adding fats, oils and grease to the plant’s digesters, we are converting unwanted waste to clean energy and keeping it out of pipes and landfills,” said Clean Water Services and Washington County Chair, Andy Duyck. “With Energy Trust’s help, we’re cutting operating costs and paving the way for wastewater treatment plants everywhere to invest in innovative renewable energy generation.”

This is the latest project where Clean Water Services and Energy Trust have teamed up to invest in projects that save and generate energy. Since 2004, Clean Water Services has worked with Energy Trust on more than 100 energy-saving improvements throughout its service area — from large-scale capital improvements to new energy-efficient lighting, pumps, drives and

operations and maintenance improvements. This has resulted in more than 9 million kilowatt hours of electricity saved per year for Clean Water Services, and lower utility bills and operating costs translates to saving for ratepayers.

The Durham Treatment Facility cleans wastewater for nearly 250,000 residents of Beaverton, Tigard, Sherwood, Tualatin, Durham, King City, and portions of Clackamas and Multnomah counties.

The $16.8 million project was funded by Clean Water Services. The agency received $3 million in cash incentives from Energy Trust and $2.8 million in tax credits from the Oregon Department of Energy.

MEDIA NOTE: Project background materials, images and video (including aerial drone and helicopter footage) from the Durham Advanced Wastewater Treatment Facility will be made available for media use here or by request. Contact Sarah Wilkinson at or 202-431-8308.

CLEAN WATER SERVICES: Everything we do at Clean Water Services aims to protect public health while enhancing the natural environment. Combining science and nature, we clean water and return it to the Tualatin River, so it can be used again. More than 560,000 customers enjoy clean water and healthy rivers and streams as a result of our innovative water management solutions, drainage management, water-quality and stream-enhancement projects, habitat protection and more. For more information, visit

ENERGY TRUST: Energy Trust of Oregon is an independent nonprofit organization dedicated to helping utility customers benefit from saving energy and generating renewable power. Our services, cash incentives and energy solutions have helped participating customers of Portland General Electric, Pacific Power, NW Natural and Cascade Natural Gas save $2.3 billion on energy bills. Our work helps keep energy costs as low as possible, creates jobs and builds a sustainable energy future. Learn more at or call 1-866-368-7878.

Category: Renewable Energy