Anti-icing and de-icing techniques for wind turbines: Critical review

Expansion of wind energy installed capacity is poised to play a key role in climate change mitigation. However, wind energy is also susceptible to global climate change. Some changes associated with climate evolution will likely benefit the wind energy industry while other changes may negatively impact wind energy developments, with such ‘gains and losses’ depending on the region under consideration. Herein we review possible mechanisms by which global climate variability and change may influence the wind energy resource and operating conditions, summarize some of the tools that are being employed to quantify these effects and the sources of uncertainty in making such projections, and discuss results of studies conducted to date. We present illustrative examples of research from northern Europe. Climate change analyses conducted for this region, which has shown considerable penetration of wind energy, imply that in the near-term (i.e. to the middle of the current century) natural variability exceeds the climate change signal in the wind energy resource and extreme wind speeds, but there will likely be a decline in icing frequency and sea ice both of which will tend to benefit the wind energy industry. By the end of the twenty-first century there is evidence for small magnitude changes in the wind resource (though the sign of the change remains uncertain), for increases in extreme wind speeds, and continued declines in sea ice and icing frequencies. Thus the current state-of-the-art suggests no detectable change in the wind resource or other external conditions that could jeopardize the continued exploitation of wind energy in northern Europe, though further research is needed to provide greater confidence in these projections.

Climate change impacts on wind energy: A review

Icephobic materials: Fundamentals, performance evaluation, and applications

Research on climate change impacts on renewable energy is becoming increasingly relevant due to the vulnerability of the sector and to the continual development of methodologies and availability of data. Public and private decision-making needs specific research. However, many gaps still exist in certain geographical regions and technologies. Providing economic estimates with a value chain perspective are also missing from most papers. This paper addresses the most relevant studies that project quantitative estimates of climate change impacts on solar, wind, hydro and other renewable generation technologies. Summary tables of impacts and projections are provided so that researchers, governments and the private sector may have an accurate view of the state-of-the-art on this topic.

/pdf/climate-change-impacts-on-renewable-energy-generation-a-39yhpb0c9r.pdf

Climate change impacts on renewable energy generation. A review of quantitative projections

Freezing of water droplets on solid surfaces: An experimental and numerical study

The wind energy market is in full growth in Quebec but technical difficulties due to cold climate conditions have occurred for most of the existing projects. Thus, icing simulations were carried out on a 0.2 m NACA 63 415 blade profile in the refrigerated wind tunnel of the Anti-icing Materials International Laboratory (AMIL). The shapes and masses of the ice deposits were measured, as well as the lift and drag forces of the iced profiles. Scaling was carried out based on the 1.8 MW–Vestas V80 wind turbine technical data, for three different radial positions and two in-fog icing conditions measured at the Murdochville wind farm in the Gaspe Peninsula. For both icing events, the mass of ice accumulated on the blade profile increased with an increase in the radial position. In wet regime testing (first icing event), glaze formed mostly near the leading edge and on the pressure side. It also accumulated by run-off on the trailing edge of the outer half of the blade. In dry-regime testing (second icing event), rime mostly accreted on the leading edge and formed horns. For both icing events, when glaze or rime accreted on the blade profile, lift decreased and drag increased. A load calculation using the blade element theory shows that drag force on the entire blade becomes too large compared to lift, leading to a negative torque and the stop of the wind turbine. Torque reduction is more significant on the outer third of the blade. Setting up a de-icing system only on the outer part of the blade would enable significant decrease of heating energy costs. Copyright © 2007 John Wiley & Sons, Ltd.

Clement Hochart

Papers

Wind turbine performance under icing conditions

Icing Simulation of Wind Turbine Blades