Lenze works with SEaB energy to turn waste into power

Drives, controllers and IIoT connectivity from Lenze are future-proofing an innovative energy from waste solution developed by SEaB Energy.

The challenges around energy have never been more acute, with governments and energy users across the globe facing two fundamental challenges: moving towards sustainable energy sources, and ensuring reliable supply. One company that sees its products as part of the solution is SEaB Energy, whose compact anaerobic digestion systems are attracting global attention.

At the heart of these innovative, sustainable energy generation systems are drives, controllers and IIoT connectivity products from Lenze, delivering flexible control whilst providing a future-proofed solution that will enable SEaB Energy to evolve its products.

Based in London, SEaB Energy was founded in 2009 by Nick and Sandra Sassow, with the goal of developing and commercialising anaerobic digestion technology to generate power from organic waste. They saw that turning this waste into energy at the point where it is generated had the potential not only to reduce on-site energy costs, but also reduce the cost of waste disposal and reduce the levels of organic waste going to landfill.

2018 saw the company launch its key products: Muckbuster for turning slurry and similar farm waste into energy, water and rich organic fertiliser, and Flexibuster to do the same with a broader range of organic food chain waste. Both were designed from the outset to be modular, containerised solutions that could be scaled up as required – ideally suited to small and medium scale sites that produce between 500kg and 6000kg of organic waste per day.

“They provide a logical and sustainable way of capturing the energy that remains in waste,” says marketing manager Bianca Sassow. “Instead of paying for this waste to be taken away and processed somewhere else, Muckbuster and Flexibuster enable companies to turn that waste into free energy and heat on-site.”

Plug and play solution

A patented process extracts energy from the waste stream in the form of biogas, which is then used to fuel a CHP engine to provide electricity and heat. Highly modular, the energy-from-waste products are built into standard shipping container units, and are delivered ready to be integrated into on-site facilities in a ‘plug-and-play’ manner. Installation lead time is just a couple of months, and once installed at sites the systems can start generating energy immediately.

Head of engineering Graeme Allen says: “The flexibility of the system is a key selling point. There are separate modules for different pre- and post-processing functions, and we can scale up the system quickly and easily with additional containers according to the amount of waste being produced at the site.”

Designed deliberately to be viable for smaller scale operations, from food production facilities and farms to the likes of hotels and hospitals, Muckbuster and Flexibuster typically achieve payback within two years.

In the process, some 4 tonnes of organic waste can generate around 40kW in electricity and the same again in heat. But the biggest benefit for many businesses comes from eliminating waste disposal costs.

There is more, too. As a byproduct, the same system can also produce some 1.4 tonnes of liquid fertiliser, as well as water. “The most common sources of fertiliser are mining and fossil fuels, both of which have huge environmental impact,” says Bianca. “Ours is a sustainable source of fertiliser with less pollution. At the same time, in urban areas where the is a big demand for water, the energy required to transport water to those areas can be enormous. We generate grey water at source, which can be used for the likes of irrigation, street cleaning, etc. It really is the epitome of the circular economy.”

Open platform

As part of its EU Horizon 2020 funded project, SEaB Energy adopted Lenze inverters to control the various pumps and monitor the valves throughout the process. “They enabled us to build, test and commission the Muckbuster and Flexibuster systems in modules in our own factory, and then deliver them to site as fully working products,” says Graeme.

Ongoing development of the Muckbuster and Flexibuster brought SEaB Energy to the point where it needed to completely overhaul the control system. “We wanted to move to an open platform with future-proofed communications, ensuring we would be able to support the widest range of on-site integration requirements,” Graeme explains. “Naturally we spoke to Lenze, but of course we also spoke to other automation vendors. In terms of meeting our specification and recognising what we were trying to achieve, the Lenze solution really stood out.”

Lenze business development manager Angelo Lafratta comments: “While we have many customers in the energy sector, this was still quite an unusual application for us. But we’re always striving to reach out to new customers, to understand their challenges and to open up a discussion around ideas that will deliver optimised solutions. And SEaB’s vision for their control system ticked all of our boxes.”

The solution proposed by Lenze was built around i550 series panel mounted inverters on the extraction fan, discharge pump, dosing pump and hopper, plus i550 Protec decentralised drive on the buffer tank. Lenze applications manager Mark Turner says: “These required less panel space, so saving associated panel costs, but they also gave SEaB Energy easier set-up and faster commissioning, as well as simpler maintenance. In addition, the highly efficient IE2 inverters will future-proof SEaB against incoming energy legislation.”

The inverters are controlled by a Lenze C520 PLC which provides the brains of the machine, connecting to Lenze IO 1000 series I/O modules to bring in the various inputs and control the outputs of the anaerobic digestion process. “The backbone of the connectivity, though, is OPC UA,” says Mark. “This is standard feature of the C520 that brings the required openness to the platform.”

IoT gateway

Lenze also integrated an X540 IoT gateway into the system, providing remote access to the machine and connection to the Cloud, with SEaB Energy currently developing a Cloud-based monitoring and control system.

“The previous system was very much a closed ecosystem, but the new technology gives us more opportunity to innovate,” says Graeme. “We position ourselves as a cutting-edge company, and the Lenze technology aligns perfectly with that vision. The use of OPC UA makes the Muckbuster and Flexibuster even easier to integrate, and future-proofs us for any future developments.”

Indeed, along with Cloud integration, the company is already forging ahead with new innovations enabled by the Lenze technology, embracing Industry 4.0 and exploring possibilities with machine learning, edge processing, vision technology and more. “Our goal is to develop more with digitalisation, to offer more in the way of asset management and fault management – to offer our customers even greater capability to reliably generate energy from waste,” says Graeme. “Lenze is helping us along that journey.”