Reducing energy costs by half is just one step towards self-sufficiency for Hopes Ash Farm in Herefordshire, where slurry is viewed as a valuable resource. British Dairying shares their journey.
“There’s so much value in slurry,” says Harry Davies of Hopes Ash Farm, located near Ross-on-Wye. “Looking to the future, we need to explore how to maximize its potential.”
After earning a BSc in Agriculture from Harper Adams University, including a dissertation on extracting nutrients from slurry, it’s no surprise that the enterprising 23-year-old is eager to implement innovative solutions.
The Davies family business, now in its fifth generation, centers around a 130-head dairy herd. They have diversified with beef, sheep, poultry, arable farming, and 100kW of solar panels. Harry, along with his father Rob and grandfather Bryan, is determined to push forward with sustainable practices. Their latest addition is an anaerobic digestion (AD) plant. Harry admits that setting up a biogas plant is complex, but the benefits are already evident.
“I knew it wouldn’t be simple,” he says. “But the rewards make all the effort worthwhile, even if the setup was challenging with issues like pipework and road closures.”
The primary challenge was transferring slurry across the road to the new AD plant. With robotically-milked cows bedded on recycled paper crumble, an automated scraper system, and a standard slurry pump, everything seemed efficient. However, Harry was focused on capturing slurry nutrients for the farm’s long-term health.
The existing pump couldn’t handle the pressure needed to move slurry over 200 meters to the new AD plant. The Davies family consulted Midland Slurry Systems (MSS), their long-time dealer, which recommended a long-shaft chopper pump from Landia.
“This would be the furthest we’ve ever asked a Landia pump to move slurry, but we were confident,” says Giles Russel, Director at MSS. “Landia pumps are durable and fully repairable. This was our biggest job of the year, ensuring all the pipework under the road was correctly installed for Hopes Ash Farm.”
The new six-inch pipework linked to the AD plant, transporting slurry from the 15kW Landia pump, which runs four times daily. The processed slurry is mixed in a 30m³ pit before being separated by a screw-press separator. The nutrient-rich solids are collected, and the liquid is stored in a 10,000-litre tank before being pumped back to the main slurry store.
“Everything is automated from the moment slurry leaves the cows,” says Harry. “Now, we’re fine-tuning the system for maximum efficiency. Weather can affect the process, particularly the slurry’s viscosity. We need it as liquid as possible, but thicker slurry has higher calorific value.”
The Landia pump runs for varying lengths depending on slurry thickness, but at 15kW, and with a 22kW AD plant, the goal is to minimize run-time.
“Some farmers pay 50p/kWh for electricity, but our AD plant reduces our cost to 30p/kWh,” Harry adds. “Plus, our solar panels make us nearly self-sufficient in renewable electricity.”
Their aim isn’t to export energy, limited by a 30kW grid restriction. “Politicians’ lack of foresight and under-investment affects us, as many farms try to adopt renewable solutions,” Harry notes.
“This includes our new separator, which adds value by placing most phosphorus in solids and nitrogen in liquids. Our soil needs organic matter to bind it together, preventing nutrient loss into waterways. We carefully balance organic manure applications to maintain soil health.”
Exporting solids sparks debates within the family, but it’s part of a well-considered nutrient plan. “Our AD plant was a smart addition to our business. Looking ahead, we need to harness its heat efficiently.”
Harry also acknowledges the learning curve with biogas suppliers. “Not all solutions fit every farm. MSS delivered what they promised, providing essential support for this investment. Reliable dealer support is crucial for creating a stable, sustainable future.”
