Reduce, Reuse, Refuel

The vast majority of capital projects undertaken at WRRFs are driven by aging infrastructure, capacity limitations, and permit compliance. Because RNG-to-pipeline projects are focused on resource recovery, garnering buy-ins from stakeholders and local governments may take some time, diligent negotiations, and finesse.

The pipeline injection project constructed three primary assets to make up the gas recovery facility:

The pipeline injection project would not have succeeded on time and under budget had it not been for open, honest, and persistent communication between all parties involved. This was never more critical than during the startup and commissioning phase when each project element was verified, tested, and integrated into a single system. During this critical time, every team member attended daily...

For the gas-conditioning system, the project team set out to develop a facility that not only generates RNG but also communicates with a regenerative thermal oxidizer (RTO) — two separate systems, each with distinct abilities and constraints, integrated into one.

In addition to being the first pipeline injection system at a WRRF in Colorado, this project was also Xcel’s first RNG-to-pipeline endeavor. As such, everything from deciding on reasonable gas quality requirements to establishing contingencies, insurance, payment, and testing requirements had to be negotiated and finalized before Xcel could begin their design work.

While the pipeline injection system’s ribbon-cutting ceremony was cause for much celebration, SPR’s work was far from complete. For several months after startup, SPR continued to work with the equipment manufacturers, in coordination with the design engineer and contractor, to adjust instrumentation set points and refine communication pathways between system components.

Because biogas-to-RNG projects can sell RIN credits and produce a revenue stream, their payback periods are typically less than 10 years, after which WRRFs can use their significant return on investment to plan future capital improvements projects they might not have otherwise been able to fund. The pipeline injection project’s payback period is projected at five to seven years, with...

With so few installations across the country, RNG-to-pipeline projects are trailblazing efforts that set precedents and standards for others to follow. While any progressive project will have its share of pushback and obstacles, success will always be found in solid and well-defined visions, dependable partnerships, frequent communication, and selective decision-making.