The task of loading lorries with feedstock for an AD plant falls squarely at the feet of two industrial high-reach handlers for one Hampshire grower. Geoff Ashcroft went to find out more.
For Apsley Farms, the challenges of growing enough maize and rye to keep its 6.5MW AD plant producing energy is one that sees the farm growing crops within a 30-mile radius of its base at the 404 hectare Faulkners Down House farm, near Andover, Hants.
The plant consumes about 110,000 tonnes of feedstock each year for power generation, which is extracted from about 1,820ha of maize and 1,820ha of rye. Most of the feedstock is clamped using temporary storage that can be sited on field headlands close to where the crops are harvested.
This gives the flexibility to haul feedstock back to Apsley Farms as required, as operations manager Edward du Val explains. “We use AgBags to clamp forage where we harvest, to simplify logistics and storage,” he says. “This lets us put around 3,500 tonnes into bags in a 12-hour shift, using two foragers and just six tractors and trailers.”
This short-haul approach keeps tractors and trailers off local roads, reducing the impact on the local community, and affords the flexibility to haul crop back to base using walking-floor articulated lorries, only when it is needed.
“When we started to look into ways of bringing crop back to the plant, lorries quickly became the only viable solution,” says Mr du Val. “With 27 tonne payloads, we can move a lot of material quickly and economically – you just would not entertain doing this with tractors and trailers.”
At peak times, the farm’s four walking-floor articulated lorries move 16-20 loads/day. And to make the most of transport efficiency, these lorries rarely run empty – each trip to collect forage sees a load of solid digestate taken out ready for spreading.
“All we had to do was work out an efficient process for loading the lorries,” he says.
The farm started to load its lorries using a telehandler, and with a 21 tonne excavator on the farm, it too was put to use, sitting on top of an AgBag to see how suitable it could be for loading lorries.
“Everything we tried was slow, cumbersome and unnecessarily complicated,” he says. “We would have needed at least a JCB 435S with a toe-tip bucket to fill trailers quickly.
“But there was too much driving about to load a lorry, and that created ruts and mess. So I took to the internet, and sought inspiration from how other markets approached materials handling,” he says.
“I really liked the German market’s approach to using wheeled excavators,” he says. “They tow trailers to and from job sites, and it got me thinking about how we could work smarter.”
It was a process that eventually led him to construction machinery firm Liebherr, which had a pair of LH30M materials handlers in its yard that had recently come back off hire. These high-reach machines are more often seen in scrap yards, waste transfer sites and recycling centres than they are on farm, but the productivity potential appealed to Mr du Val.
“These are like wheeled excavators on steroids,” he says. “They use a long-reach boom for lifting, rather than digging, and with an elevating cab to create a better view of the work area, I could see how beneficial these could be for loading lorries.”
A deal was done and the then two-year old, low-houred machines arrived at Apsley Farms just three years ago. The standard industrial twin-wheels were replaced by ag-spec flotation tyres, and the end of the lifting arm was equipped with a five cubic metre capacity clam-shell bucket.
Now with over 4,000 hours on their clocks, Mr du Val is struggling to see a better way of rehandling forage into bulk transport. “The performance is superb. We can load 27 tonnes of maize in just seven minutes,” he says. “That is faster than most farms can load a grain lorry. Perhaps the only drawback is having to move them using a low-loader.”
The LH30M boasts a 14m reach, and with a hydraulically elevating cab, is able to put the operator’s line of sight anywhere up to a working height of 5.4m, which simplifies loading of high-sided vehicles.
“We have so much operating flexibility,” he says. “When we open up an AgBag, the machine can move onto the plastic sheet that is the base of the bag; as the feedstock is moved, the operator can use the clam shell to pull the sheet up from behind, cleaning up as it moves forward.
“What it has done is made us think about AgBag locations,” he says. “There is enough reach to rehandle silage from two bags sat side-by-side. We can also reach over a hedge too, as long as there’s a track or road on the other side for lorry access – you could not do that with a telehandler or wheeled loader.
“And these Liebherr machines have an auto engine stop-start, like most modern cars,” he says. “After three minutes of idling, the engine will stop – and that also saves us a lot of fuel.”
Operator Andy Spreadbury (pictured above) has plenty of praise for the LH30M materials handler. “It was a little scary at first, but you soon get used to the high seating position, which makes loading lorries easy,” he says.
“There is plenty of power and the hydraulics are smooth and powerful too,” he says. “The engine only runs at 1,700rpm, so it is quite a calm environment.”
Having spent time on excavators in the past, Mr Spreadbury says the joystick controls were easy enough to grasp.
“Using a clam shell bucket mounted on a 360 degree rotating headstock, it is just so different to using a bucket,” he says. “Though you can be quite precise with the controls.”
I can also use the clam shell like a finger-and-thumb to pick up the top sheets for folding, and to make it easy to clean-up behind me.”
He says that the handler also has a built-in dynamic weighing system, which lets him total the payload as the clam shell swings over the walking floor trailers. “The lorries have on-board weighing too, but it gives me an idea when handling wetter or dense forage crops,” he says. “I need around 25-26 buckets of rye to fill a lorry, but only 16-17 of maize.”
He prefers to load facing downhill, as it helps to spot the edge of the clam shell bucket on the ground, without danger of nipping the sheet. “You soon work out the best ways to position and work the machine, and use the elevating cab to your advantage,” he says.
“And I only move forward after every lorry load, which minimizes any driving around. I simply lift the outriggers, drive forward, then put the outriggers down,” he adds. “There are times when we sit the outriggers on plastic grids to help spread the weight on softer ground, but when you do not run around loading, you do not make any mess.”