Colorado renewable natural gas-to-pipeline project lauded for environmental and economic benefits
DENVER – Carollo Engineers, Inc. (Carollo), South Platte Renew (SPR), and J.R. Filanc Construction Company (Filanc) have received the Water Environment Federation’s (WEF) prestigious 2020 Project Excellence Award for the $7.8-million SPR Gas Recovery Facility and Pipeline Injection Project. This annual distinction pays tribute to innovative projects and programs in the water sector. The 2020 project winners were honored during WEF’s virtual Technical Exhibition and Conference, WEFTEC Connect, on Oct. 7.
The award-winning project designed and constructed the first system in Colorado to convert raw biogas from a water resource recovery facility (WRRF) to renewable natural gas (RNG) and inject that product into a natural gas pipeline for downstream use as transportation fuel. The new gas recovery facility is anticipated not only to deliver vast environmental benefits to local communities but also to generate a valuable revenue stream for SPR.
“The Pipeline Injection Project is a unique approach in innovation that will benefit our environment, our customers, and our facility,” said SPR Director Pieter Van Ry. “We are beyond excited to share this pioneering accomplishment with our communities.”
SPR operates the third largest WRRF in Colorado, treating nearly 20 million gallons of wastewater a day from 300,000 residents in Littleton, Englewood, and 19 other connecting communities. The facility has a permitted capacity of 50 million gallons per day and generates approximately 500,000 cubic feet per day of biogas through anaerobic digestion.
In 2016, SPR hired Carollo to evaluate sustainable and cost-effective options to beneficially reuse the WRRF’s biogas, which was one of the focus areas of SPR’s 2014 Energy Improvement Program. Carollo recommended that SPR install a biogas-upgrading system that treats biogas and injects RNG directly into a nearby natural gas pipeline owned and operated by the Public Service Company of Colorado, a subsidiary of Xcel Energy. Carollo designed the upgrading system, which removes carbon dioxide, hydrogen sulfide, siloxanes, moisture, and volatile organic compounds from raw biogas.
“While the technology used to convert biogas to RNG is established, pipeline injection projects remain few and far between in the U.S.,” said Carollo project manager Becky Luna. “Project success required stakeholder buy-in and extensive coordination with Xcel Energy. We commend SPR for their vision and steadfast commitment to reducing greenhouse gas emissions.”
This project exemplifies the utility’s commitment to environmental stewardship. Since being commissioned in October 2019, the pipeline injection system has successfully met Xcel Energy’s stringent gas quality requirements, which has allowed SPR to offset the equivalent of 2,000 gallons of gasoline per day and more than 13.5 million petroleum-fueled passenger vehicle miles per year. This translates to a reduction of more than 5,000 metric tons in fossil-fuel-based carbon-dioxide emissions per year.
Beyond its environmental merits, pipeline injection also provides a relatively rapid return on investment, thanks to incentive credits from the U.S. Environmental Protection Agency’s Renewable Fuel Standard Program. Just in 2020, the gas recovery facility is projected to receive $1.5 million in revenue and has an overall project payback of five to seven years.
This innovative project was delivered with a construction manager/general contractor (CMGC) delivery model for the construction phase with Filanc serving as the CMGC contractor. SPR also hired carbon broker Bluesource to sell both the RNG (brown gas) and green credits (renewable identification numbers) associated with the injected gas.
“Like any pioneering project, there were some twists and turns to navigate, and we applaud SPR on their hard work and dedication,” said Luna. “Through their well-defined vision, dependable partnership, frequent communication, and attitude toward continual learning, they have set precedents and standards for others across the country to follow.”