That wind turbines often contain many hundreds of liters of oil isn't a fact that many talk about. In part because this aspect doesn't exactly emanate green signal value, though it plays a quite modest role in practice. And partly because it's just boring; not least of all when the oil, used to lubricate hydraulic components and transmission, becomes so dirty that it needs changing, with everything that entails of work hours and downtime.
But Danish subsupplier Hydratech Industries thinks it has found a solution. Alongside Britain's Delta-Xero, which makes oil filters for the somewhat larger gas, oil and nuclear turbines, the hydraulics company has developed a filtering system that can filter particles of a size down to 0.1 micron.