If you’ve ever flown a kite, you’re aware that the higher you go, the stronger the wind becomes. As a result, the height of wind turbine towers is increasing. From base to nacelle, towers can now reach heights of up to 100 meters, or approximately 30 floors. These massive turbines have a blade span that exceeds that of the Airbus 380, the world’s largest passenger airliner.
Turbine blades get longer as towers get taller, which helps collect more wind. Turbines can spin and create power at lower speeds by using lighter, stronger materials like carbon fiber or sophisticated textiles (the same composite materials used in next-generation airplanes). A new turbine, for example, may enhance output by up to 15% by increasing its diameter from 103 meters to 120 meters.
The world’s most powerful turbine, as of 2017, has a rotor diameter of 164 meters and is rated at 9.5 megawatts.
What can be done to improve turbines?
Wind Turbine Performance Improvement Techniques
- Transmission with variable speeds.
- Generator with a constant speed.
- Load and RPM programming that is sophisticated.
What can we do to improve wind energy?
When facing directly into the wind, solitary wind turbines create the highest power. However, for wind farms with densely packed lines of turbines facing the wind, wakes from upstream generators can interfere with those downstream. The wake from a wind turbine affects the production of turbines behind it, similar to how rough water from a boat in front slows a speedboat.
According to a new Stanford study, pointing turbines slightly away from oncoming wind, known as wake-steering, can reduce interference and enhance both the quantity and quality of power generated by wind farms, as well as cut operational costs.
“We need to develop ways to create a lot more electricity from existing wind farms to fulfill global targets for renewable energy output, said John Dabiri, professor of civil and environmental engineering and mechanical engineering and senior author of the article. “Traditionally, the performance of individual turbines in a wind farm has been the focus, but we need to start looking about the farm as a whole, not just the sum of its parts.
Downwind generators can lose up to 40% of their efficiency due to turbine wakes. Researchers previously utilized computer simulations to show that misaligning turbines from the prevailing winds could increase downstream turbine production. However, until now, demonstrating this on a real wind farm has been hampered by difficulties in locating a wind farm willing to shut down routine operations for an experiment and calculating the ideal angles for the turbine.
First, the Stanford team devised a more efficient method of calculating the best misalignment angles for turbines, which they detailed in a research published in the Proceedings of the National Academy of Sciences on July 1.
Then, in partnership with operator TransAlta Renewables, they put their calculations to the test on a wind farm in Alberta, Canada. In low wind speeds, the farm’s overall power output increased by up to 47 percent, depending on the angle of the turbines, and by 7 to 13 percent in typical wind speeds. The ebbs and flows of power that are typical of wind power were also decreased via wake guiding.
“Through wake steering, the front turbine produced less power as we expected,” said Michael Howland, a mechanical engineering PhD student and the study’s primary author.
However, we discovered that the downstream turbines produced substantially more power due to reduced wake effects.
What is the most serious issue with wind turbines?
Wind energy, like all energy sources, has the potential to harm the environment by reducing, fragmenting, or degrading habitat for wildlife, fish, and plants. Additionally, rotating turbine blades might endanger flying fauna such as birds and bats. Because of the potential for wind power to have a negative impact on wildlife, and because these difficulties could delay or prevent wind development in high-quality wind resource areas, impact reduction, siting, and permitting issues are among the wind industry’s top goals.
WETO supports in projects that strive to describe and understand the impact of wind on wildlife on land and offshore to address these concerns and encourage environmentally sustainable growth of wind power in the United States. Furthermore, through centralized information hubs like Tethys, WETO engages in operations to collect and disseminate scientifically rigorous peer-reviewed studies on environmental consequences. The office also invests in scientific research that allows for the development of cost-effective technology to reduce wildlife impacts at both onshore and offshore wind farms.
WETO strives to foster interagency collaboration on wind energy impacts and siting research in order to ensure that taxpayer monies are used wisely to solve environmental challenges associated with wind deployment in the United States.
Listed below are a few of WETO’s investments:
- For more than 24 years, the office has supported peer-reviewed research, in part through collaborative relationships with the wind industry and environmental groups including the National Wind Coordinating Collaborative (NWCC) and the Bats and Wind Energy Cooperative.
- The NWCC was established in 1994 by the DOE’s wind office in collaboration with the National Renewable Energy Laboratory to investigate a wide range of issues related to wind energy development, such as transmission, power markets, and wildlife impacts. The NWCC’s focus has evolved over the last decade to addressing and disseminating high-quality information about environmental impacts and remedies.
- In May 2009, the Department of Energy’s wind office announced approximately $2 million in environmental research awards aimed at decreasing the hazards of wind power development to vital species and habitats. Researchers from Kansas State University and the NWCC’s Grassland Community Collaborative published a paper in 2013 that revealed wind development in Kansas had no significant impact on the population and reproduction of larger prairie chickens.
- The Bats and Wind Energy Cooperative has been involved in numerous research projects funded by DOE’s National Renewable Energy Laboratory since its inception in 2003, including studies evaluating the impact of changing the cut-in-speed of wind turbines (the minimum wind speed at which wind turbines begin producing power) and the use of ultrasonic acoustic deterrents to reduce bat impacts at wind turbines.
- Through a competitive funding opportunity, WETO is also financing research and development projects that increase the technical preparedness of bat impact mitigation and minimization solutions. Bat Conservation International, Frontier Wind, General Electric, Texas Christian University, and the University of Massachusetts are among the companies, universities, and organizations receiving funding from the Energy Department to field test and evaluate near-commercial bat impact mitigation technologies, which will provide regulators and wind facility owners-operators with viable and cost-effective tools to reduce bat impacts.
- Through a competitive funding opportunity, WETO is also financing research and development projects that increase the technical preparedness of bat impact mitigation and minimization solutions. Bat Conservation International, Frontier Wind, General Electric, Texas Christian University, and the University of Massachusetts are among the companies, universities, and organizations receiving funding from the Energy Department to field test and evaluate near-commercial bat impact mitigation technologies, which will provide regulators and wind facility owners-operators with viable and cost-effective tools to reduce bat impacts. The Status and Findings of Developing Technologies for Bat Detection and Deterrence at Wind Facilities webinars hosted by the National Wind Coordinating Collaborative provide project updates and testing findings as of March 2018.
- WETO chose six teams in 2016 to work on improving solutions that will safeguard eagles that share airspace with wind turbines. For breakthrough, vital eagle-impact minimization technology research and development projects, more nearly $3 million was allocated across the six teams. The research financed by this grant will equip wind farm owners and operators with practical and cost-effective strategies for reducing potential eagle impacts. This important study expands on the Energy Department’s efforts to facilitate wind energy deployment while also ensuring animal coexistence by addressing siting and environmental concerns. If the study is successful, it will safeguard wildlife while also giving new tools for the wind industry to reduce regulatory and financial concerns.
- WETO is a supporter of research on biological interactions with offshore wind turbines. With this funding, researchers are gathering crucial data on marine life, offshore bird and bat behavior, and other factors that influence the deployment of offshore wind turbines in the United States. The Biodiversity Research Institute and a diverse group of collaborators, for example, completed the largest ecological study ever conducted in the Mid-Atlantic to produce a detailed picture of the environment in Mid-Atlantic Wind Energy Areas, which will aid permitting and environmental compliance for offshore wind projects.
WETO also collaborates with other federal agencies to create recommendations to help developers comply with statutory, regulatory, and administrative requirements for wildlife protection, national security, and public safety. The Wind Energy Technologies Office, for example, collaborated with the Department of the Interior on the Land-Based Wind Energy Guidelines and Eagle Conservation Plan Guidance.
What role will wind turbines play in the future?
- Wind energy is available all throughout the country. Wind can be a feasible source of renewable electricity in all 50 states by 2050, according to the Wind Vision Report.
- A strong domestic supply chain is aided by wind energy. By 2050, wind might support over 600,000 jobs in manufacturing, installation, maintenance, and related services.
- Wind energy is a cost-effective option. With increased wind, the electric utility sector is expected to be less subject to fluctuation in natural gas and coal fuel prices, as wind generation agreements typically give 20-year fixed pricing. Wind is expected to save customers $280 billion by 2050 by lowering national sensitivity to price spikes and supply disruptions through long-term pricing.
- Wind energy lowers pollution levels in the atmosphere. In 2013, wind energy averted the release of almost 250,000 metric tons of air pollutants such as sulfur dioxide, nitric oxide, nitrogen dioxide, and particulate matter by operating at full capacity. Wind energy has the potential to prevent the emission of 12.3 gigatonnes of greenhouse emissions by 2050.
- Wind energy helps to conserve water. Wind energy has the potential to save 260 billion gallons of water by 2050, which is the equivalent of about 400,000 Olympic-size swimming pools that would have been utilized in the electric power sector.
- The use of wind energy boosts a community’s earnings. By 2050, local governments will be able to collect $3.2 billion in additional tax revenue via land lease payments and property taxes.
Download the complete study to learn more about the conclusions of the Wind Vision Report. Learn more about the achievements in wind energy in the two years following the publication of the Wind Vision Report.
In Chapter 4 (The Wind Vision Roadmap: A Pathway Forward) and Appendix M, the Wind Vision report concludes with a roadmap of technological, economic, and institutional initiatives to maximize wind’s potential contribution to a cleaner, more reliable domestic energy generation portfolio (Detailed Roadmap Actions).
What progress has been made in wind energy throughout time?
Production of Energy Has Increased Stronger production capacity is achieved by using larger blades and higher turbines. In comparison, a decade ago, the average turbine could produce 1.5 megawatts of electricity. Since then, their capacity has increased, with GE’s Haliade X presently being the largest.
Technology Trends and Recent Developments
The majority of SWTs currently in use around the world have three blades, however there are variants with two, four, or even more blades at the micro-scale. The rotor diameter is less than 20 meters, but most commercial tiny wind turbines have rotor diameters of less than 10 meters. These turbines are commonly positioned on 12 to 24 meter towers.
In the case of the rotor, technical trends are moving toward enhanced blade manufacturing processes based mostly on alternative manufacturing techniques including injection molding, compression molding, and reaction injection molding.
Shorter manufacturing times, cheaper part costs, and improved reproducibility and homogeneity are all advantages, but tooling costs are greater.
For the following reasons, most modern SWTs use a synchronous permanent magnet generator based on rare earth permanent magnets as the electromechanical converter:
- Rare earth permanent magnets are displacing ferrite magnets because they have higher magnetic characteristics and prices have been steadily declining.
- As a result, generators are more compact and lighter.
Reduced generator ‘cogging’ torque, which improves low wind speed start-up, is a key feature to achieve in permanent magnet generators.
Induction generators are still used by some manufacturers.
However, no turbines with a rated output of less than 50 kW have employed induction generators directly connected to the grid in recent years.
Currently, however, systems that use induction generators to bypass power electronics are resurfacing in order to save money and enhance dependability.
The inverter, also known as a DC/AC converter, is a pricey component for grid-connected SWTs.
The majority of the inverters utilized are from the PV sector and have been modified for use with wind turbines after being put downstream of voltage control devices.
Inverters designed specifically for wind turbines have recently begun to exist in single-phase and three-phase versions.
International Power Quality and EMC (electromagnetic compatibility) standards can be used to certify these.
SWTs are now intended for low wind speeds in general, which means larger rotors, taller towers, and precise gust management mechanisms. The turbine is usually sheltered from severe winds by yawing or ‘furling,’ which means the rotor is passively moved out of the wind by aerodynamic forces. Stall control, dynamic brakes, mechanical brakes, and pitch control (both centrifugal and active) have all been developed as alternatives to furling.
Reduced operating and peak rotor speeds are being pursued in order to reduce noise emissions.
As a result, the standard design tip speed ratio is 5:1.
New SWT design standards (IEC 61400-02, second edition) were established in 2006 for turbines with a rotor area 2 (rotor diameter of 16m), with the industry gradually adopting this standard.
The industry is diversified, and the maturity of manufacturers varies greatly.
Over 300 different versions (in varying phases of development) are available worldwide, with US producers engineering 100 of them.
The following is a summary of recent advancements in the field of small wind turbines:
- At very high wind speeds, active pitch adjustments are used to sustain energy capture.
- Sound-dampening vibration isolators;
- Blade design and manufacturing techniques that are cutting-edge;
- In the event of strong winds, there are other options for self-defense.
- Adapting a single model for use on or off the grid;
- Wireless display modules and software;
- The nacelle (rotor hub) has inverters built in.
- Electronics that have been built to fulfill stricter safety and durability requirements;
- Interconnection systems that are ready to use;
- Attempts to improve the visual appeal of SWT; and
- Turbines can be integrated into existing tower constructions, such as utility poles or lighting poles.
How can we reintroduce wind power as a viable source of energy?
Wind power has only recently become a source of toxic waste that winds up in landfills, thanks to the introduction of plastic composite blades in the 1980s.
Larger wind turbines may now be built nearly entirely out of wood, not just the blades, but also the remainder of the structure, thanks to new wood production technologies and design. This would eliminate the waste problem while also making wind turbine manufacture less reliant on fossil fuels and mined resources. The wood for the next generation of wind turbines could come from a forest planted between the turbines.
Is it true that wind turbines are more environmentally friendly?
Wind is a renewable source of electricity. In general, using wind to generate energy has less environmental consequences than many other energy sources. With few exceptions, wind turbines do not emit pollutants into the air or water, and they do not require water for cooling. Wind turbines may help lessen total air pollution and carbon dioxide emissions by reducing the quantity of power generated from fossil fuels.
The physical footprint of a single wind turbine is relatively tiny. Wind farms, or clusters of wind turbines, can be found on open land, on mountain ridges, or offshore in lakes or the ocean.
What is the efficiency of wind turbines?
Wind turbines turn wind into energy at a rate of 20% to 40% efficiency. A wind turbine has a 20-year average life expectancy, with six-monthly maintenance necessary.
What are the disadvantages of wind turbines?
Wind is a clean, renewable energy source that is also one of the most cost-effective ways to generate electricity. On the negative side, wind turbines can be noisy and unattractive aesthetically, and they can sometimes have a negative impact on the physical environment. Wind power, like solar power, is intermittent, which means that turbines are dependent on the weather and hence aren’t capable of generating electricity 24 hours a day, seven days a week.