Harnessing Methane for Greener Operations

Tapping into a renewable natural gas project for the first time, Interstates recently worked with Englewood, CO-based Gevo to build a central biogas purification site and connect it to three different dairies in Northwest Iowa. Interstates provided Gevo with power distribution, PLC design and construction, programming, instrumentation, and heat trace work.

Renewable Natural Gas is a Growing Industry
Sustainably managing fertilizers to harness renewable energy is a hot industry. This plant, known as RNG, will capture the methane released from dairy manure and refine it to be used as renewable natural gas, reducing the greenhouse gas footprint at these dairies while producing low-carbon fuels. The methane will be transported via the Northern Natural Gas pipeline.

Staci Bogue-Buchholz with Gevo says, “This is one of several projects in the region that are converting manure to methane. For the farmer, this project provides another revenue stream and addresses environmental issues by capturing greenhouse gases. It will also help control odor and provide feedback to the farmer to help control water usage.”

Automation Centralizes Control
Each dairy now has an in-ground digester to capture methane from cow manure, which is then transported to the RNG facility for refinement. The cycle involves many types of equipment and vendors, which required intense coordination. According to Robert Phillips, Automation Manager at Interstates, “Part of our job was to pull back data from each vendor control system and display this data onto the main plant control system.” This advanced controls automation means Gevo can now check levels and tweak processes from a centralized dashboard. Interstates also hard-wired permissives between the vendor control systems and the main plant. “This makes sure that the facilities can still operate even if communication is lost between two control systems,” says Phillips.

Integrated Approach Adds Value
The project faced challenges related to material and equipment delays, but it helped to have several Interstates teams working as one. “One of the very nice things about this project was the continued teamwork throughout the many challenges, supply chain schedule changes, and the whole project,” says Bogue-Buchholz.

Phillips noticed that using an integrated approach with electrical, instrumentation, engineering, and controls allowed for quicker problem-solving to keep Gevo’s project progressing. “We were able to identify barriers and offer solutions to drive the project forward,” he says.

Having a dedicated start-up coordinator also added value. According to Jim Haack, Senior Project Manager at Interstates, “This kind of biogas project was new to most of the contractors, so we brought on Dallas Hoffman, our start-up coordinator, to handle checkout and commissioning. His coordination efforts helped our superintendent keep track of vendors and develop a checkout plan.” Providing a start-up expert helped Gevo conquer any issues with commissioning and eased the transition to a fully operational plant.

Interstates’ flexibility and depth of expertise allowed us to support the client through equipment delays and contractor departures. Gevo’s Bogue-Buchholz says, “Interstates was able to engage substantial resources with little notice to cover the diverse electrical and control system needs required for the simultaneous build at four sites. They provided valuable feedback for the final design and provided engineering services as needed to ensure the successful final product.” Upon completion, the Gevo Northwest Iowa RNG project will produce approximately 355,000 MMBtu of renewable natural gas per year.