Since its inception in 1987, POET has been creating practical solutions to big problems at the intersection of energy and agriculture. Now the company has risen to that challenge once again, but in a new way, handling the engineering, procurement, and construction of a waste-to-energy system serving a cluster of dairy farms near Estelline, South Dakota.
Energy production has become an increasingly widespread part of waste management in recent years. This is especially true in industries with large amounts of organic waste, which serves as a renewable raw material. This includes agriculture, food processing, and wastewater treatment, where biowaste can be converted into biogas, biofuels, or other renewable energy sources through advanced waste-to-energy technologies.
;void('');)
Dairy farms deal with more than their fair share of biowaste in the form of manure. It’s typical for manure to be washed into holding ponds called “lagoons,” where it remains until later being used to fertilize pastures. In this environment, the manure begins to break down and release methane into the atmosphere. This is significant because methane traps heat much more effectively than carbon, leading experts to believe that methane emissions may be responsible for a quarter or more of the global temperature changes being measured today.
Enter digesters — enclosed systems that use microbes to break down manure and capture the resultant methane instead of releasing it. After manure is digested, nutrient-rich digestate can be used as fertilizer (a higher-quality fertilizer that improves soil health, according to some dairy farmers), while the captured methane can be purified and turned into renewable natural gas, or RNG.
By increasing the supply of RNG, projects like this help reduce reliance on fossil natural gas, which remains a major contributor to carbon emissions. RNG can be used in its place, providing a cleaner alternative for heating, electricity generation, and other uses of energy. As more industries and utilities transition to renewable energy sources, RNG helps with the decarbonization of sectors that have historically depended on fossil fuels.
“This project represents wins for everyone involved,” said Brandon McLellan, POET Director of Project Management. “Methane is prevented from getting to the atmosphere, which benefits everybody, and the farms have new income streams and more efficient operations. Then there are the buyers and end users of the natural gas, who now have a more sustainable energy source.”
;void('');)
The point about income streams is an important one. Requiring large investments and long-term commitments, these kinds of projects have to come with bankable results. For dairy farmers, those results can take many forms, including substantial federal tax credits, participation in carbon offset markets, the direct sale of RNG, and more. In addition, of course, they’re getting a practical, straightforward, and environmentally sound system for managing millions of pounds of waste.
“It was also a great project for us as a team,” added McLellan. “Value-add agriculture is what we’re passionate about at POET, and it’s nice to take that passion and our unique expertise in the area and apply those to new designs and customers.”
When asked if the uniqueness of the project presented any challenges for POET’s engineering team, Senior Process Engineer Jim Geraets had this to say:
“The biggest learning curve for us wasn’t on the technical side. It was more about incorporating new processes, especially for procurement, logistics, and communication, to account for the needs and wishes of different owner groups and other stakeholders.”
Working with new vendors and design criteria, Geraets pointed out, required additional effort from POET to ensure all specifications were met and construction could be undertaken as efficiently as possible. This included extensive communication with overseas suppliers and modifying certain parts and equipment to meet the National Electrical Code.
;void('');)
Safety standards and protocols get special attention in a waste-to-RNG project, where flammable gases are handled under pressure, corrosive sulfur compounds can lead to equipment failure or dangerous working conditions, and reliable containment is crucial. POET’s engineers proved more than capable and were able to draw on the company’s long history of creating operationally resilient systems and managing complex risks in design.
“All in all, it went very smoothly,” said Geraets. “We’re a small, nimble team, and that helps us diagnose and solve problems quickly. As always, we learned some things along the way, and we’re definitely prepared to take on similar projects going forward.”
The project was described as “substantially complete” at the beginning of 2025 and, at full capacity, is expected to produce enough RNG to power around 14,000 residential homes annually. In the grand scheme of renewable energy supply, it represents a small step. But for dairies looking to grow their bottom line and simultaneously manage their environmental impact, investing in a waste-to-energy scheme can be a huge leap forward.
More broadly speaking, each viable project in the waste-to-energy landscape further spreads awareness and demonstrates the potential benefits, which can extend to whole communities in the form of reduced emissions and cleaner air quality. For POET, the work done is proof positive of a continued focus on merging sustainable innovation with agricultural processes. In the long run, that simply means working together to create a better world for everyone.
