Denmark [Renewable Energy World Magazine] The world’s largest independent rotor blade manufacturer, LM Glasfiber of Denmark, and two Danish partners are developing a laser-based wind sensing system integrated into a wind turbine’s blades and spinner. They have claimed success for the system in predicting wind direction, gusts and turbulence.
The three-year research project began in 2009 with financial support from the Danish National Advanced Technology Foundation. The R&D is conducted as a joint venture with sustainable energy research organization Risø DTU and sensor specialist NKT Photonics. Among the main project objectives are that the laser-based solution will significantly improve wind turbine load control during operation, improving overall turbine reliability by acting as an efficiency enhancement and operational lifetime-boosting measure.
LM Glasfiber has been working for years on multiple projects aimed at improving rotor blade efficiency as a means to raise wind turbine energy yield. A key objective is developing ‘intelligent’ blades that continuously measure the approaching wind and either adapt to these prevailing wind conditions or supply data to the wind turbine control system, says Lars Fuglsang, LM Glasfiber research director. Integrating Lidar technology into the blades themselves is an extension of LM Glasfiber’s previous blade monitoring technology, he adds.
The partners look to have made rapid progress for their new product development, which has been named ‘wind Lidar’.
Risø DTU claimed during the first half of January 2010 that it had completed the world’s first successful test on a wind turbine with a laser-based anemometer built into the spinner in order to increase electricity generation.
Fuglsang adds, ‘Whereas current blade monitoring technologies measure loads on the blades, integrating Lidars into the blade enables us to measure the exact wind conditions to which these blades are exposed. And instead of realizing afterwards what the force upon a blade has been, we will be able to measure wind real-time and either have the blade or the wind turbine react instantly.’
The combination of Lidar technology integrated into the rotor blades as well as into the spinner is said to further optimize the system’s overall capability to ’see’ the wind well ahead before it hits the blades.
It is claimed that with the new technology incorporated energy yield may increase up to 5% over the wind turbine’s 20 year lifetime, primarily because it will be possible to use longer blades by maintaining the same wind turbine structural stress level. A 5% yield increase would, for a 4 MW class wind turbine, also result in an annual financial gain in the range of $38,000, depending on fossil energy prices and other variables.
LM Glasfiber expects a rotor blade prototype with integrated Lidar technology to be available in 2012, potentially allowing the partners to supply LM’s customers with Lidar-enabled intelligent blades by 2014.
For an in-depth look at Lidar technology, check out Eye on the Wind, in the January/February issue of Renewable Energy World magazine.