Renewable energy company Ameresco has begun commercial operations at a renewable natural gas (RNG) plant in Phoenix, Arizona.


Image: Ameresco opens renewable natural gas plant in Arizona. Photo: Courtesy of Emilian Robert Vicol/Pixabay.

Ameresco claims that the RNG plant at 91st Ave is one of the largest wastewater treatment biogas-to-RNG facilities of its kind in the US. The plant has a processing capacity of 3,250 standard cubic feet per minute (scfm) of raw digester gas produced at the wastewater treatment plant (WWTP).

The 91st Ave wastewater treatment plant is owned by Phoenix, Glendale, Mesa, Scottsdale and Tempe, which are member cities of the sub-regional operating group (SROG). The City of Phoenix operates the plant.

In February 2017, the company and the City of Phoenix broke ground on the multi-million-dollar wastewater treatment biogas utilization project and the project has become operational two years later.

Ameresco executive vice-president Mike Bakas said: “This project exemplifies innovation in action and is a model for municipalities across the globe. We commend the City of Phoenix and the SROG member cities for both their commitment to sustainability and their initiative to derive economic benefit from a previously undervalued asset: biogas from wastewater. We’re thrilled to be a long-term partner to the City of Phoenix and proud to help the region reduce its reliance on fossil fuels.”

Last month, Ameresco was selected by the City of Troutdale, Oregon,for a $2.2m turnkey project under an Energy Savings Performance Contract (ESPC). As part of the contract, the company will upgrade blowers, diffusers, UV system, distribution piping, and lighting throughout the 20-year-old wastewater treatment plant.

The city selected Ameresco using an energy savings performance contract (ESPC), which sets a maximum implementation cost for the project and is expected to bring energy savings.

For the contract, the company has been given the responsibility of designing, installing, commissioning and verification of the project. Improvement measures will include replacing the aeration basin blower, installing ultra-fine bubble diffusers, upgrading the UV disinfection system, installing new HVAC controls, and retrofitting lighting fixtures with LEDs.

Additionally, the new water distribution piping has been designed to reuse water from effluent well, reducing the plant’s need for potable water.