Exploring Biogas Opportunities in Agriculture

In this episode, we are talking to consultant, Philip Marr and Agrii‘s Crop Inputs Specialists John Charlton and Matt Richardson.

Today we are at the World Biogas Expo at the NEC in Birmingham, where a summary of results from the Brotherton iFarm forage trials and biogas plant were presented.

We will be looking into those findings asking where are the key opportunities both financial and agronomic for the farm business.

What is Anaerobic Digestion and an AD Plant?

Philip: Anaerobic digestion, often shortened to AD, is the process of producing methane, hydrogen, and CO₂. The methane is used for either gas-to-grid or to run combined heat and power (CHP) engines, generating electricity that feeds into the grid. That’s the basic principle of an AD plant.

Growing Interest in Biogas on Farms

John: It’s a developing industry. Rising gas prices and the volatility in commodity markets mean that farmers are looking at new options. An AD plant not only provides energy but also improves the rotation in arable systems and offers crop nutrition benefits.

Matt: Absolutely. In my area in Yorkshire, we’re seeing more farmers inquiring about AD plants. With the pressure of managing grass weeds and rising input costs, growing crops for energy production is becoming increasingly appealing.

Research at Brotherton: Finding the Best Crops for AD Plants

Philip: At Brotherton Farm, we’ve been running trials for 20 years. The two brothers at the farm approached me about eight years ago to explore options for powering an AD plant. We initially evaluated maize, hybrid rye, and beet as potential feedstocks.

However, we eventually ruled out beet due to logistical challenges. Rye and maize, on the other hand, have been effective, especially for weed control. By continuously growing rye, we’ve managed to completely eliminate resistant ryegrass from fields.

Biogas Benefits Beyond Energy Production

While we usually think of AD plants as a means of energy production, here we see additional benefits for weed management. How valuable is that,?

John: It’s essential. Effective grass weed control is fundamental to long-term crop production. As agrochemical options become limited, rotational control through crops like rye is increasingly valuable.

Why Maize and Hybrid Rye Are Ideal for AD Plants

Philip: When deciding which crops to use in an AD plant, we found that a 75% maize and 25% rye mix produced optimal methane levels. This balanced ratio helps maximize the energy output from the plant, with Brotherton’s AD plant consuming around 40 tonnes of material per day.

The Role of Crop Input Specialists in Optimizing AD Feedstocks

Philip: Selecting the right crop varieties is crucial. For hybrid rye, we need varieties that offer high forage yields. We also differentiate between forage-specific, dual-purpose, and grain-specific varieties to meet the specific needs of each AD plant.

John: We work closely with farmers on varietal selection, crop nutrition, and even storage best practices to ensure they’re getting the most from their AD feedstocks.

Brotherton: A Valuable Trial Site

Could you tell us more about the Brotherton trial site?

Matt: Brotherton is in West Yorkshire, near Knottingley. It’s a hub for testing different cropping strategies and understanding which varieties work best for biogas production. The site allows us to trial different forage varieties and generate data that helps other farmers integrate AD crops into their operations.

How Can Farmers Start Growing for AD Plants?

John: It doesn’t require massive adjustments. Farmers just need to approach these crops with a different mindset—thinking in terms of forage rather than grain production. With guidance, growing hybrid rye or maize for AD becomes quite straightforward.

Connecting Farmers to AD Plants

Philip: I actively track planning permissions for AD plants, helping farmers connect with local AD facilities. In areas like Scotland, where late harvests make it challenging to grow crops like oilseed rape, we’ve seen great success with hybrid rye as a forage crop. This helps farmers manage rotations and keep their fields productive.

Advice for Farmers Considering AD Crops

Matt: Farmers just need an open mindset. We have answers to their questions, and with the resources at Brotherton, they can feel confident about integrating AD crops into their operations.

John: Absolutely. Forage crops offer a stable, reliable income stream, which can be incredibly valuable for family farms.

Philip: Farmers can reach out to me directly, and I’ll happily walk them through the entire process. We’ve guided many through the setup of their AD plants and can connect them to potential investors if needed.

In Conclusion: Why AD Plants Are Worth Considering

Philip: The opportunity is there for everyone. My advice is simple: accept, adopt, and adapt. AD plants represent a stable income stream and a valuable addition to any farm business.