July/August 2020

40 n RENEWABLE ENERGY July/August 2020 www.drivesncontrols.com Yacht-inspired turbine blade could deliver cheaper energy A novel lightweight composite wind turbine blade, wrapped in a high- tech textile shell, has been developed by a spinoff from a UK yacht-sail developer. It is up to a third lighter than standard fibreglass blade designs, can be made longer to generate more energy and could, ultimately, make offshore wind – already one of the cheapest energy sources – even easier and cheaper to harness. The blade can change its shape to control loads. According to Dr Sabrina Malpede, chief executive of the developer, Edinburgh- based ACT Blade: “It is 32% lighter than conventional blades, enabling it to be 10% longer and directly contributing to the production of 9% more energy.” She believes that the blade’s lower manufacturing costs could disrupt the market. “The ACT Blade is not only the lightest but also the most modular blade,” says Malpede. “That means we use components that can be manufactured in parallel, using smaller and therefore cheaper tooling, reducing costs by 60%. It also requires less space – its factory will be 47% smaller than those of conventional blades – and less energy, which makes the manufacturing process less expensive compared with those of conventional blades.” ACT Blade, founded in 2015, developed its blade in response to an innovation challenge launched by the Offshore Renewable Energy (ORE) Catapult, aimed at improving the performance of wind turbine blades and generating “cleaner, greener power in ever deeper waters”. Dr Malpede, who made her name designing sails for fast yachts, responded with a game-changing idea: take the light, durable structure of yacht sails and adapt the technology to improve the performance of offshore wind turbine blades. A 13m-long prototype blade was completed in February this year and was tested at ORE Catapult’s National Renewable Energy Centre in Blyth in April. The results showed that the blade could withstand extreme loads and every type of direction and twist, going beyond those likely to be experienced in operation. The prototype blade, produced under an Innovate UK-funded project, was manufactured and tested in collaboration with a consortium of research partners including the University of Sheffield’s Advanced Manufacturing Research Centre (AMRC), the Lightweight Manufacturing Research Centre (a sister centre to the University of Strathclyde’s Advanced Forming Research Centre), as well as the ORE Catapult. John Halfpenny, who led the AMRC team that worked with colleagues from the High Value Manufacturing (HVM) Catapult at the Lightweight Manufacturing Centre, predicts that the new blade“could be a major disruptor in the renewable energy sector”. As turbine blades are made longer to generate more energy, they become heavy and expensive to produce, install and maintain, he points out. The ACT Blade manufacturing process is less energy- intensive than for conventional blades, offering significant cost, sustainability and environmental advantages. “The ACT Blade is lighter, lower cost, has increased efficiency and will be easier to recycle,” Halfpenny explains. “This is a real game-changer for offshore renewable energy with considerable benefits to be gained – not only by new wind farm developers but for existing wind farm operators – to improve performance, reduce costs and cut carbon emissions in the manufacturing process.” To validate the new blade design, the AMRC performed FEA (finite element analysis) that helped to locate potential problems in the design, including areas of tension and weak spots, before producing CAD data to optimise the structural design of the prototype. The AMR team also designed patterns, moulds and fixtures to manufacture the blade. With the help of several UK engineering research organisations, a UK start-up has developed a “game-changing”wind turbine blade, based on yacht sail technology, that is extremely light and produces more energy than conventional designs. ACT Blade CEO Dr Sabrina Malpede has adapted her expertise in designing sails for yachts Photo: Wattie Cheung