Electricity and Control April 2024

ENERGY MANAGEMENT + THE INDUSTRIAL ENVIRONMENT

Energy optimisation in the timber sector

Large timber and paper companies have led the way in generating their own power using steam turbines.Today, the timber sector generates its own power using its own by-products – and can create a new income stream from the biomass it produces. Dennis Williams, Commercial Director at operations and maintenance service provider on steam systems and boilers, Associated Energy Services, reports on some of the work it has done to help companies optimise their energy plant performance.

Ensuring plant reliability and safety The timber industry contributes up to five per cent of South Africa’s gross domestic product and involves a complex value chain. AES (Associated Energy Services) has worked with sawmills and related downstream businesses for many years. “One can be sure that somewhere in the value chain, thermal energy is required to condition or soften wood chips – or to dry them,” Williams says. Companies oper ating in the sector therefore need to ensure their energy plants are efficient, reliable and resilient in the face of rising input costs and broader economic pressures. Working with tissue manufacturers, a kraft paper pro ducer and a large board manufacturer, AES has helped improve boiler efficiency, steam quality and boiler reliabil ity, and in cleaning up and reducing emissions through its operations and maintenance (O&M) services, including en ergy plant upgrades and project management. Safety and asset care are always priorities. As many plants in the timber sector are old, Williams emphasises that pressure vessel safety is crucial. AES’s ISO 45001 cer tification (managing occupational health & safety risks) – including the management and legal compliance of boilers – is therefore particularly important. Similarly, the compa ny’s ISO 9001 (quality management systems), ISO 14001 (environmental management systems) and ISO 45001 cer tifications in energy plant operations and maintenance set AES apart from competitors. This is key in the timber sector, as the company is often responsible for the operation and maintenance of clients’ energy plants on sites in remote lo cations. It also offers clients on-site training and management for boiler and energy plant staff. On some sites this entails bridging language differences and providing literacy train ing where needed. “In this way, we have been privileged to make a real difference for the staff participating – unlock ing further career path growth – and an improved quality of life,” Williams highlights. Extended services Over the past decade, AES has witnessed significant re alignment within the timber value chain. “We are now en gaging with companies looking to invest in new plant and equipment, providing them with systems that support more

The timber value chain usually originates in remote locations.

efficient use of energy and water and economies of scale – currently key operational and economic considerations.” AES also works with clients to plan how best to use and manage the volumes of biomass they generate. “We look for solutions that enable the company to use as little of this resource as possible, so they can on-sell the rest. Getting the right balance is key,” he says. Related to this, AES is assisting clients in other sectors to source greener fuels– such as timber biomass – where those clients are wanting to offset the use of fossil fuels by using biomass to fire their boilers. However, there are challenges. High fuel costs mean transport of biomass from rural sawmills is expensive. Dis tances travelled could also unintentionally increase users’ carbon footprint as they seek to improve sustainability. So, the calculations need to be done. “Furthermore, as timber biomass has a low calorific val ue, the actual fuel content per mass is low and bulky: load ed onto a 30-tonne vehicle, it might yield only 11 tonnes of fuel. If loaded with coal, there will be 25 to 26 tonnes of ma terial with a far higher calorific value – potentially double – depending on how much moisture is in the wood biomass,” Williams explains. Another challenge is the cost of biomass – a central de ciding factor for new plant investment: “It comes down to economics. The originator wants to sell it for the best pos sible price. So, while the burning of biomass is preferable

APRIL 2024 Electricity + Control

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