Confidential Client
Southeast USA
Power & Energy, Renewables
Renewable Natural Gas Development from Agricultural Waste and Landfill Gas
Overview
As industries continue seeking sustainable alternatives to traditional energy sources, renewable natural gas (RNG) has emerged as an important solution for reducing greenhouse gas emissions while creating value from previously underutilized waste streams. One renewable energy developer and its subsidiary are advancing multiple projects focused on converting agricultural waste and landfill gas into renewable natural gas and other marketable byproducts. These projects support the growing demand for lower-carbon energy solutions while helping agricultural producers, landfills, and communities reduce environmental impacts associated with waste management.
The development program includes a multi-year portfolio of facilities designed to process animal and agricultural waste using proprietary conversion technology, as well as the continued expansion of landfill biogas-to-RNG facilities. Collectively, these projects help transform organic waste materials into renewable energy resources that can be injected into existing natural gas infrastructure while supporting broader sustainability and carbon reduction goals.
Nexus Engineering Group was engaged to provide technical and project development expertise to support project planning, scope development, and early-stage engineering activities. The primary objective was to help advance multiple renewable natural gas projects by defining project requirements, evaluating technical solutions, developing conceptual designs, and establishing the execution framework necessary to move these projects toward implementation.
Challenge
Developing renewable natural gas facilities that utilize agricultural waste and landfill gas presents several unique technical, operational, and logistical challenges. Unlike traditional energy projects, these facilities must manage complex feedstock collection, handling, processing, and gas treatment requirements while maintaining the reliability needed for commercial-scale operation.
Feedstock Collection and Processing
One of the primary challenges involved developing systems capable of collecting, transporting, and preparing large volumes of agricultural waste for processing. Organic waste streams often contain significant moisture content and varying material characteristics, requiring specialized handling, dewatering, and conditioning systems before entering the conversion process. The projects also required careful consideration of solids and liquids separation, intermediate storage, and material transport systems to ensure safe and efficient operations.
Gas Quality and Pipeline Integration
Both agricultural waste and landfill gas applications required robust gas cleanup strategies capable of producing renewable natural gas that meets stringent pipeline quality requirements. Designing systems to remove impurities and consistently deliver gas suitable for injection into existing natural gas infrastructure added significant complexity to project development and facility planning efforts.
Multi-Site Development and Early-Stage Planning
The projects encompassed multiple facilities at varying stages of development, requiring coordinated planning across different technologies, locations, and project stakeholders. Establishing clear equipment requirements, execution strategies, utility infrastructure needs, and cost expectations during the early phases of development was critical to supporting future engineering and execution efforts. Additionally, power infrastructure requirements, including substation planning and grid integration considerations, needed to be evaluated alongside process and facility design activities.
Solution
Nexus addressed these challenges through a collaborative project development approach that combined engineering expertise, project controls knowledge, and practical execution planning. By working closely with the client's development teams, Nexus helped establish the technical foundation necessary to advance these renewable natural gas projects toward implementation.
The team provided comprehensive system analysis and process modeling to evaluate facility performance and support design decision-making. Nexus developed conceptual process flow diagrams (PFDs) and site layouts that defined facility configurations, identified infrastructure requirements, and established project execution strategies. These early-stage engineering efforts enabled stakeholders to assess technical feasibility, evaluate alternatives, and align project objectives before advancing into subsequent development phases.
In addition to process and facility planning, Nexus supported power infrastructure assessments, including substation planning, while providing execution planning, scheduling, and estimating services to establish realistic project expectations. The team also contributed basis of design development, instrumentation planning, and scope definition activities that supported informed decision-making and helped reduce project risk as development progressed.
Outcome
Through technical rigor, flexibility, and a collaborative delivery approach, Nexus helped position these renewable energy projects for long-term success. Following the successful completion and operation of a pilot facility, the process was replicated and scaled for full commercial deployment, increasing production capacity approximately sixfold. Leveraging proven technologies, operational data, and lessons learned from the pilot plant helped validate key process assumptions, optimize facility design, and reduce risk as the projects advanced toward implementation.
While the original development plan for one of the major RNG projects focused on producing renewable natural gas (RNG), continued evaluation of operating conditions and gas composition revealed that the gas stream was better suited for power generation rather than pipeline-quality RNG production. As a result, the project evolved into a biogas-to-energy solution, utilizing the gas as a fuel source for electrical power generation. This flexibility allowed the development team to maximize the value of the resource while maintaining the project's sustainability objectives and creating a viable long-term renewable energy solution.
By supporting the conversion of agricultural waste and landfill gas into valuable renewable energy resources, the projects contribute to sustainable energy development while creating environmental and economic benefits for the communities they serve. The successful pilot program established the technical foundation for future expansion efforts and demonstrated the viability of scaling the technology for larger commercial applications.
Services Provided
- Conceptual Engineering & Design Input
- Process System Modeling
- Initial System Analysis
- Conceptual Process Flow Diagram (PFD) Development
- Site Layout Development
- Basis of Design Support
- Power System Analysis
- Substation Planning
- Instrumentation Planning
- EPC Project Scheduling
- Cost Estimating
- Project Development Support
- Review of EPC Deliverables
Project Director
Marty Ellman - Market Segment Leader & Senior Project Director
About Nexus Engineering Group
Nexus Engineering Group is a full-service, independent engineering, procurement, and construction management (EPCm) firm headquartered in Cleveland, Ohio, with offices in Toledo, Ohio; Columbus, Ohio; Midland, Michigan; and Oak Brook, Illinois. Founded in 2005, Nexus partners closely with clients to support project goals from concept through startup, delivering practical, reliable solutions across the refining, petroleum midstream, chemical, manufacturing, power & energy, and renewables markets.
Nexus integrates engineering, procurement, and construction management services to help clients plan and execute complex projects with confidence. Through close collaboration and a client-first approach, Nexus supports informed decision-making, manages project risk, and delivers practical solutions that enhance safety, reliability, and long-term project value.
