Intellectual property (IP) is a double-edged sword in every industry. The marketplace rewards companies with the best innovations. In aggregate, these technology advances accelerate competitiveness and improve the offerings to the marketplace. However, companies pay princely sums and engage small armies of attorneys and experts to vigorously pursue and defend IP advantages over their peers. These battles churn out winners and losers on a regular basis and can often stifle the broader progress of an industry.
The wind power industry has had its fair share of IP battles. One of the latest fights is over so-called de-rated operation. Late July saw a U.K. court rule in favor of Siemens over ENERCON. ENERCON has been defending its IP over its Storm Control solution, which is its name for de-rated operation.
De-rated operation is the ability of a wind turbine to operate below its maximum capacity during times of high wind speed. Traditionally, when a wind turbine reaches its threshold for maximum wind speed (around 25 meters per second), it will enter a cut-out shutdown mode to protect the turbine from damaging high winds.
The traditional process takes the electricity production offline, which can destabilize the broader power grid. As the commercial-scale deployment of wind turbines increases, this becomes a larger concern. To address this concern, de-rating allows a turbine to remain online, using a range of control methods from pitch control of blades to generator torque control to operate a wind turbine at below its maximum capacity.
For example, instead of a 2 MW wind turbine shutting off once it encounters its threshold cut-off wind speed parameters, it can reduce its output to 50% capacity, or 1 MW. This ensures that the wind plant remains operational, balancing the electrical grid, and that kilowatt-hours continue to be produced instead of lost due to a full shutdown. There are also economic inefficiencies associated with stopping and restarting wind turbines that can be avoided by running at reduced load. This approach can also be used to continue the operation and revenue generation of a wind turbine that is experiencing high operating temperatures within the turbine drivetrain. De-rating can allow power production to continue while temperatures are reduced to acceptable levels without entirely shutting the turbine down.
ENERCON said that Siemens’ High Wind Ride Through (HWRT) infringed on ENERCON’s Storm Control system. Judge Justice Biress of the London High Court ruled the challenge invalid in favor of Siemens. Some of the technical aspects of prior art, or known technology, that bolstered Siemens’ case are well-cited at Windpower Monthly. In short, the judge accepted submitted evidence that previous technology existed–and was even obvious for de-rated operation, ramping generation down as wind speeds went up.
Making an Appeal
ENERCON says it is considering its options for appeal. In the meantime, the U.K. decision may sway how the issue is interpreted by the European Patent Office (EPO), which would have reverberations across the European market. Should the U.K. ruling stand, and the EPO meet a similar conclusion, this ruling will produce a broader benefit to the wind industry, allowing de-rated approaches from Siemens and other vendors.
ENERCON is among the most highly respected wind turbine companies, with solid performance and reputation, and it has always been on the leading edge of innovation and should be lauded for it. But if this case means more efficient and cost-effective wind technology is available for most or all wind turbine vendors, then wind plant owners, electricity consumers, and anyone with a vested interest in more clean generation are winners.