All the Right Parts
This summer, CPS Energy marked the third anniversary of an innovative partnership that is fueling San Antonio’s public bus fleet with renewable natural gas.
By working together with local partners to source, deliver and supply RNG, the utility is helping reduce emissions, extend the life of its natural gas system and provide a model that other utilities can learn from. “This first-of-its-kind RNG project for CPS Energy highlights our strategy to think globally and act locally to bring innovative solutions to our community,” said Rudy D. Garza, president and CEO, CPS Energy.
In 2021, CPS Energy partnered with VIA Metropolitan Transit (San Antonio’s public transportation provider), EDL and Republic Services, to begin supplying RNG for use in VIA’s compressed natural gas buses. Waste gas captured from the local Republic Services landfill is processed, cleaned by EDL, then injected as RNG into CPS Energy’s natural gas distribution system. That gas is then delivered to VIA’s fueling stations, where it is used to keep buses rolling across the city.
VIA operates nearly 450 CNG buses fueled by natural gas, and RNG offers a way to lower emissions without requiring significant infrastructure changes. In 2024, this partnership provided more than half of VIA’s fuel. “We are converting the community’s waste into a lower-carbon fuel source that reduces greenhouse gas emissions and brings us closer to our goal of beneficially reusing 50% more of our biogas by 2030,” said Republic Services General Manager Bill Rich.
While every city has its own unique needs, the model demonstrates how natural gas utilities can play a pivotal role in advancing cleaner transportation without sacrificing reliability—and that RNG can be integrated into existing gas infrastructure and transit systems in a practical, cost-effective way.
“RNG is playing a key role in generating clean, home-grown energy for San Antonio,” said Anthony Falbo, EDL North America CEO. “We’re proud to see the success of partnerships like this, where EDL works closely with our customers to achieve reliability and sustainability goals, while making a positive impact on local community and residents.”
Other utilities considering a similar partnership can look to the following lessons CPS Energy learned from the first three years:
- Leverage existing infrastructure. VIA already operated a CNG fleet, and CPS Energy already had the pipeline infrastructure in place. By using what was already built, the transition to RNG was cost-effective and efficient.
- Start local. RNG sourced from nearby landfills reduces transportation costs and highlights the circular economy benefits of using waste streams to create clean fuel.
- Engage early with partners. CPS Energy, VIA, EDL and Republic Services invested time up front to align on priorities, including emissions goals, cost considerations and fuel supply reliability. This early collaboration built trust and streamlined the launch.
As the partnership celebrates three years of success, the organizations are exploring opportunities to expand RNG use and further enhance San Antonio’s sustainability strategy. With transportation accounting for a significant share of greenhouse gas emissions, the project underscores how natural gas utilities like CPS Energy can lead in advancing low-carbon solutions that make an immediate impact—providing practical, scalable, and sustainable solutions that benefit communities today and tomorrow.