With a background in solar energy and procurement, and a passion for turning waste into something positive, brothers Maxwell and Billy Bagnall saw developing an AD plant as the next natural step for their business. However, as Maxwell openly admits, the reality was much tougher than either of them had anticipated. “When we took over the site in January 2014, we had just 12 months to get our plant up and running, because of the FIT deadline. We were never in any doubt that we could achieve it – in fact, we started commissioning just nine months later – but there were definitely issues along the way.”
“Our biggest hurdle was finance,” admits Maxwell. “We found that investors would say ‘yes’ right until it came to transferring the funds – at which point their answer changed to ‘no’. We dug in our heels and never gave up, constantly changing our plans until we got the answers we needed. In the end, the plant was financed by a combination of self-funding, asset funding, local development grant funding, and crowd funding.”
The plant’s location was perfect (next to a waste management site at the back of an industrial estate), and BioDynamic’s application sailed through planning, receiving zero objections. But other areas weren’t quite so straightforward. “As well as the issue with funding, the site had an active maggot farm, which had to be removed before we could start work. Then, once we became operational, we realised that our calculations for pasteurisation were incorrect – our pasteurisation system worked fine up to 500 kW, but as we ramped up our operations during the commissioning phase, we hit problems. We had no option but to re-engineer the plant and bring in additional tanks.”
One area which has caused the brothers no concerns, however, is the performance of their digester. They made a decision very early on to hand over the biological management of the plant to FM BioEnergy, who were recommended by another operator. Tim Elsome is Business Development Manager for FM BioEnergy and praises BioDynamic UK for securing expert help from the start. “Often, we are brought in to deal with the aftermath of a biological issue. It’s far better for an operator to avoid such issues in the first place, as the results of a digester failing can be catastrophic. BioDynamic used our start-up consultancy service, which successfully guided them through the tricky commissioning phase. We supplied a feeding plan, additives and analysed the plant’s performance twice a week to ensure it was brought up to full capacity in the shortest timeframe. We had one unexpected issue, which highlighted the fact that the pump was over-delivering and shock loading the system at times. We also identified an issue with the variable feedstock dry matter content. We advised them to change their pumps and invest in some basic lab equipment to ensure better process control.”
BioDynamic now has its own laboratory equipment and tests regularly in-house. “We consult and advise the company based on its in-house results, and also provide a bespoke mix of trace elements, which is reviewed every three months,” adds Tim. “This keeps the operation stable and robust, meaning BioDynamic is in a good position to consider any offers of feedstock that may arise.” Maxwell has a final word of advice for any would-be developers: “I now know this plant like the back of my hand and, despite the hurdles, it’s been a joy. But as a first-time operator, it’s important to know your limitations – to keep your plant running safely and efficiently, go to an expert. Our AD operation is now going from strength to strength, and we expect to be running at full capacity by the end of this year.”
Article courtesy of AD and Bioresources News (Issue 29, page 26)