BHS Partners with Napa Recycling and City of Napa for Renewable Natural Gas Facility

March 31, 2026

Print This Article Share it With Friends

(Zero Waste Energy) The project includes a Zero Waste Energy dry anaerobic digestion system. -- In a unique Public-Private Partnership, BHS (Bulk Handling Systems) is partnering with Napa Recycling and Waste Services (Napa Recycling) and the City of Napa in the development and operation of an industry-leading dry anaerobic digestion and renewable natural gas (AD-RNG) facility at the existing Napa Recycling and Composting Facility.

“We are excited to be partnering with the City of Napa, and Napa Recycling on this important carbon reducing project,” said Eric Herbert, President of Zero Waste Energy and BHS.

The AD-RNG facility features Zero Waste Energy’s SMARTFERM® Plug Flow system which is specially designed to recover the energy content from Napa Recycling’s existing organic waste stream in the form of biogas. The facility will provide the City of Napa with the ability to produce renewable natural gas (RNG) while also significantly reducing greenhouse gas emissions.

“This project virtually eliminates methane emissions from organic waste being disposed of from the service area,” said Herbert. “Additionally, we will also replace the fossil fuel derived gas used by the trucking fleet with renewable natural gas generated from organic waste converted onsite. A truly circular solution.”

The AD-RNG facility is estimated to generate up to 500,000 diesel gallon equivalents of CNG annually; enough to power approximately 50 heavy-duty waste collection trucks or similar high mileage vehicles per year. The renewable natural gas (RNG) generated will be used to fuel Napa Recycling’s fleet of waste collection trucks. The facility can also utilize its RNG to generate electricity for the fleet should local regulations require refuse and recycling fleets to transition to electric-only vehicles.

Frequently Asked Questions

What happens to the composting program at the Napa Recycling and Composting Facility?
The composting program at the Napa Recycling and Composting Facility will continue. Instead of being sorted and processed straight to composting, a portion of the organic waste will feed the new anaerobic digestion system. The remaining solids will be diverted to the existing composting system.

Who is Zero Waste Energy?
Zero Waste Energy (ZWE) is the organics technology division of BHS. Specializing in systems engineering and development in anaerobic digestion and compost, ZWE has over 15 years in the industry. Developed by ZWE and utilized by BHS, anaerobic digestion technology is widely used to meet sustainability and organic waste reduction goals.

What is SMARTFERM®?
SMARTFERM® is an advanced, dry anaerobic digestion technology designed to transform organic waste into renewable biogas, high-grade compost, and electricity. It provides a closed-loop solution for the waste industry, converting waste into renewable natural gas (RNG) to power collection vehicles while reducing landfill usage.

Where can I learn more about the Napa Renewable Resources project?

City of Napa Solid Waste & Recycling Division: https://www.cityofnapa.org/488/Solid-Waste-Recycling-Division
Napa Recycling & Waste Services: http://naparecycling.com/
Zero Waste Energy website: https://zerowasteenergy.com/our-projects/city-napa-napa-recycling-waste-services

Related resources and references

Rep. Mike Thompson applauds Napa Renewable Natural Gas project powered by Inflation Reduction Act tax credits
The Press Democrat coverage on the February 3 Napa City Council Meeting
CalRecycle grant award
February 3 Napa City Council meeting
The Business of Trash, Q&A with Kevin Miller, City of Napa

For more information about this topic please contact BHS marketing department at 541-868-1313 or marketing@bhsequip.com.

Zero Waste Energy (ZWE) is a global project developer utilizing patented anaerobic digestion (AD) technology and resource recovery processes to solve pressing problems in the waste industry throughout North America. Founded in 2009 by parent company Bulk Handling Sysmtems (BHS), ZWE designs, builds, and operates integrated solid waste facilities that efficiently optimize waste diversion and generate renewable energy in an environmentally sound manner. Collectively, ZWE’s management team has over 100 years of experience in solid waste, recycling, composting and biogas recovery. READ MORE

Related articles

REP. MIKE THOMPSON APPLAUDS NAPA RENEWABLE NATURAL GAS PROJECT POWERED BY INFLATION REDUCTION ACT TAX CREDITS (Office of Congressman Mike Thompson (D-CA 4th))
Napa’s Next Phase: Anaerobic Digestion Joins a Mature Composting System (BioCycle Magazine)

Excerpt from Office of Congressman Mike Thompson (D-CA 4th): Congressman Mike Thompson (CA-04) applauded the City of Napa’s new anaerobic digestion system, a transformative clean energy project that will convert organic waste into renewable natural gas to power the city’s garbage and recycling trucks. The project is utilizing federal clean energy tax incentives secured by Congressman Thompson under the Inflation Reduction Act, including the 30% Investment Tax Credit (ITC) and an additional 10% Domestic Content Bonus Credit.

“This is a major win for Napa and for our climate,” said Thompson. “Instead of sending food scraps and organic waste to landfills where they produce harmful methane emissions, this system will capture that gas and turn it into clean, renewable fuel to power our city’s fleet. I'm proud to see the Inflation Reduction Act’s clean energy tax credits I secured are helping communities like Napa take real action on climate change while creating local jobs and strengthening American manufacturing.”

“This project has been over 15 years in the making and will further reduce our reliance on fossil fuels,” said Napa City Councilmember Beth Painter. “It is a model for how a small city like Napa can take big steps to address climate change. Congressman Thompson’s tax credits made this project possible. I could not be more proud of all who have contributed to this project.”

"We are excited to be partnering with the City of Napa, and Napa Recycling on this important carbon reducing project,” said Zero Waste Energy President Eric Herbert. “Not only will this project eliminate methane emissions from organic waste being disposed of currently from the service area, we will also be replacing the fossil fuel derived gas used by the trucking fleet with Renewable Natural Gas (RNG) generated from organic waste converted onsite. A truly circular solution. We appreciate the support that the ITC provides to this project. As an American manufacturing company, we are able to realize the full value of available credits offered through that program. Job creation, cleaner communities, and decarbonization is the result."

The $30 million project will be constructed at the Napa Materials Diversion Facility, operated by Napa Recycling & Waste Services, and is expected to be operational by mid-2027.

Once complete, the system will:

Process between 32,000 and 44,000 tons of organic waste annually
Generate approximately 350,000 diesel gallon equivalents of renewable natural gas each year — enough to fuel 36 waste collection trucks
Reduce greenhouse gas emissions equivalent to removing approximately 21,000 passenger vehicles from the road over 10 years

In addition to producing renewable natural gas, the system will generate compost and liquid fertilizer as byproducts, further advancing Napa’s sustainability goals and helping the city meet state climate requirements. READ MORE

Excerpt from BioCycle Magazine: A defining feature of Napa’s approach is how it routes different organic materials through the system based on their energy potential. Rather than treating all incoming organics the same, the facility is designed to separate streams and direct them to the most appropriate processing pathway. Residential organics, which are largely composed of yard trimmings and soiled paper, are sent primarily to composting due to their relatively low methane potential. Commercial food waste, by contrast, is prioritized for anaerobic digestion (AD).

“What you’re looking for is the high methane fraction,” said Kevin Miller, Materials Diversion Administrator for the City of Napa. “Commercial routes can be 50% to 70% food waste, sometimes even higher, and that’s where the gas is.”

The AD system is initially designed to process approximately 44,000 tons per year with a mix of one-third food waste and two-thirds green waste. Over time, Napa plans to shift that ratio toward a higher proportion of food waste to increase biogas production and overall system efficiency.

Regional factors also influence feedstock composition. Napa’s location in a major wine-producing region introduces materials such as grape pomace and winery byproducts, which are well suited for AD due to their high energy content. Even destructed bottled wine is expected to be incorporated into the system as a supplemental feedstock.

Integrating Digestion and Composting

The AD system is not designed to replace composting, but to contribute to it. This integration is particularly important in California, where landfill diversion requirements limit disposal options for organic residuals. Digestate must be further processed, and composting provides the pathway to produce a usable end product while maintaining compliance with state regulations.

“In practice, you can have CASP without anaerobic digestion, but you can’t have anaerobic digestion without CASP,” Miller said, referring to the facility’s covered aerated static pile system. For Napa, that meant building out composting infrastructure first before layering in AD.

A Long Development Arc

While the technology integration is forward-looking, the path to implementation has been long. Napa first evaluated AD as part of a broader infrastructure plan more than 16 years ago.At the time, composting upgrades were considered essential, while AD was viewed as an opportunity that would depend on economics. That distinction shaped the project’s timeline.

...

A $3 million grant awarded in 2014 ultimately had to be returned when the City could not meet construction timelines before the funding expired. The composting system was not completed until 2020, delaying the feasibility of digestion.

The project only became viable once multiple financing mechanisms aligned. A $10 million CalRecycle grant, combined with federal investment tax credits secured by the private partners, ultimately closed the economic gap and made the project feasible.

Economics, Operations, and Stability

From the City’s perspective, the value of the system spans multiple dimensions, including emissions reduction, cost savings, and energy production. The project is designed not only as a climate solution, but also as an operational and financial asset that supports long-term system stability.

In the near term, one of the most significant benefits comes from reducing the volume of material that must be transported offsite. The digestion process results in approximately 18% mass reduction, effectively increasing onsite capacity and avoiding disposal costs. That translates to roughly 6,000 additional tons of processing capacity per year and an estimated $270,000 in annual savings.

Longer term, the system provides energy price stability by allowing the City to produce its own renewable fuel. That control insulates the City from fluctuations in global fuel markets while aligning with local climate action goals.”We’re going to own the RNG station,” Miller said.

Operationally, the system also improves fleet efficiency. Vehicles can be fueled overnight through a slow-fill system, eliminating the need for mid-route fueling and reducing downtime.

Structuring the Partnership

...

Planning for Future Flexibility

While the system is designed around RNG, Napa is already considering how it may evolve. The facility includes the ability to use biogas for electricity generation if regulatory conditions shift, particularly as California continues to push toward electrification of vehicle fleets. The design reflects a broader strategy of building flexibility into long-lived infrastructure. READ MORE