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Wind energy in need of further development

Wind energy Energy production Energy systems Electricity supply
Researchers from DTU Wind Energy and an international group of colleagues are highlighting the need for further scientific and innovation breakthroughs within wind energy.

The total global capacity of installed wind turbines have increased tenfold since 2005 as per an estimation from the World Wind Energy Association. In 2005, the total global capacity was 59 Gigawatt rising to almost 600 GW in 2018. For the past five years, new capacity of roughly 50 GW have been added every year.

One would think that this trajectory is ensuring that wind energy will become a primary source of sustainable, low-cost energy in the future. However, the wind turbines installed by the end of 2018 only covered close to 6% of the global electricity demand.

In an article in Science, an international group of scientists from Denmark, USA, Norway, Sweden, Finland, Spain and Germany are highlighting the urgent need for further scientific and innovation breakthroughs within wind energy.

Head of Section at DTU Wind Energy, Katherine Dykes, is one of the lead authors of the article along with Paul Veers and Eric Lantz from the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL).

In fall 2017, NREL convened more than 70 wind experts representing 15 countries to discuss a future global electricity system where wind could serve as the primary source of energy. Based on this workshop, the article lead authors identified three “grand challenges” in wind energy research that require further progress from the scientific community.

“Wind energy can become the backbone of the green energy system, but grand research and innovation challenges must still be overcome,” says Katherine Dykes.

“There are substantial opportunities for research and innovation breakthroughs in wind energy on and offshore. In fact, these breakthroughs are likely to come if the scientific community works together to solve three grand challenges in wind energy. In this article, we pose a call to action to the greater scientific community to come together to solve these three wind energy grand challenges in order to realize the full potential of wind energy and the green transition.”

These grand challenges are:

1. Improved understanding of the wind resource and flow in the region of the atmosphere where wind power plants operate.

As wind turbines increase in height to capture greater energy resource and wind plants spread over greater distances, we need to understand the dynamics of wind at these elevations and scales. Past use of simplified physical models and basic observational technology has allowed for installation of wind power plants and predictions of performance in a variety of terrain types. However, major gaps exist in our knowledge of wind flows in complex terrain, intra- and inter-plant flows, interaction of wind and water in offshore environments, and more. We need to understand those differing conditions so that wind plants can be optimized, cost-effective, and controllable—and installed in the right locations.

2. Addressing the structural and system dynamics of the largest rotating machines in the world.

Wind turbines are now the largest flexible, rotating machines in the world, with blade lengths exceeding 80 meters and towers rising well above 100 meters. To put this in perspective, three of the largest passenger aircraft—Airbus A380-800s—could fit nose-to-nose within the swept area of one wind turbine rotor. As machines continue getting larger, new materials and manufacturing processes are needed to address the emerging issues of scalability, transportation, and recycling. In addition, the intersection of turbine and atmospheric dynamics raises several important research questions. Many simplifying assumptions on which previous generations of wind turbines were designed no longer apply. We need to understand the complex and dynamic behavior of the next generation of machines interacting with the wind flows that come down into and through the plant.

3. Designing and operating wind power plants to support and foster grid reliability and resiliency.

High wind and solar penetrations will drastically change the electricity grids of the future. Wind can provide essential services that help to ensure the grid operates reliably at all times. Innovative controls could leverage the attributes of wind turbines to optimize plant energy output while also supplying these grid services. For instance, using big data techniques on information from sensors distributed on turbines around wind plants could enhance energy capture, reduce cost, and optimize operations to meet grid requirements. The path to realizing this future will require substantial research at the intersections of atmospheric flow modeling, individual turbine dynamics, and wind plant control with the larger electric system operation.

These wind research grand challenges build on each other. Characterizing the wind power plant operating zone in the atmosphere will be essential to making progress in designing the next generation of even larger low-cost wind turbines. Understanding both dynamic control of wind turbines together at the plant level and forecasting the nature of the wind flowing in will enable the control of the plant needed for grid support.

Urgent need for further development

According to the article, overcoming these challenges will enable the innovation necessary to realize wind energy’s full potential - not just providing cheap electrons, but also forming the backbone of a future energy system that functions as a fundamental part of the green transition.

Co-author Anna Maria Sempreviva, Senior Scientist at DTU Wind Energy, whose specific contribution to the article was on the importance of data science and data management in reaching the three objectives, states that the complexity of the three grand challenges necessitates a transdisciplinary approach from the entire field of wind energy science:

“Scientific breakthroughs behind innovation originate from programs integrating the effort of experts from several disciplines that might appear disconnected. In this view, the availability of big data across different scale and disciplines and specifically data management is crucial for an efficient digitalization. This is a call for industry to act in synergy with academia, share data to test new hypothesis, or evaluate new methods supporting the generation of new products, processes and business models.”

This may also ensure that the wind energy sector remains economically attractive for investors and consumers, as the cost of energy from wind continue to decrease.

While the wind energy sector has come a long way in the past decade, the article underlines the urgent need for further development. It outlines the necessary steps in moving from the 6% of the global electricity demand supplied today towards a future in which wind energy contributes one-third to more than one-half of consumed electricity, and in which instantaneous local levels of wind-derived power may exceed 100% of local demand, as it sometimes does in Denmark.

“Solving these grand challenges, in wind energy physics, machine dynamics, and system science and control, will require integrated research programs involving scientists and engineers from across the world,” says Katherine Dykes, and adds that Denmark is uniquely positioned to remain integral to this research and innovation:

“Denmark has led the way with industry and research communities working together to make wind energy one of the cheapest ways to generate electricity today. If it continues to do so, Denmark will remain, as it has been for over a century, a beacon in wind energy for the entire global community.”