As wind technology expands in scale and productivity, experts are looking for ways to increase energy capture while lowering costs.
Opportunities and Challenges examine options for increasing the height of wind turbine hubs—where the turbine motor and rotors attach—and situations and places where taller towers might have the most significant impact.
This article aims to educate people about the prospects and potential of increased wind turbine hub heights and ways to improve wind technology performance of a tall tower technology as a critical component of wind energy advancement.
Taller towers can access more significant wind resources that occur at higher elevations beyond the reach of conventional turbines today. In addition, higher tower height on wind turbines helps limit interference from trees, buildings, and other topographical features. Finally, it gives extra clearance for longer blades, boosting energy extraction per turbine.
The Rise of A Tall Wind Turbine Towers
In 2000, there were only a handful of modern wind turbines. Today, over 52,000 generate about 6 percent of global electricity. Wind industry power growth is accelerating too. Wind makes up two-thirds of all renewable energy capacities installed in the United States since 2008.
The US National Renewable Energy Institute analysis on towers estimates that increasing the height of wind turbines tower from 80 meters to 140 meters will almost double the entire country’s wind production. Wind turbines are the most cost-effective at 140 meters.
Greater Effect of Taller Towers
Higher wind speeds up to the critical speed are usually desired for wind energy generation. Still, higher turbulence levels are generally not intended because fluctuations in wind speed reduce the wind turbine’s energy production.
Higher hub heights are essential because of the more powerful wind resource available at higher above-ground levels. The taller towers also provide more clearance for longer blades. Wind turbine researchers, designers, and engineers continue to develop solutions that could require even higher hub heights to be economically appealing.
Tower Height As A Dynamic Design
Increased hub heights have historically stemmed from a general trend of better wind resources at higher elevations where surface roughness has less impact and slows movement (e.g., trees, structures) on local topography and wind direction.
Fundamentally, tower height development has been seen to impact installation and erection costs and the added cost of taller tower heights compared to the more energy that wind turbines may produce from the upgraded wind resource quality discovered at higher above-ground altitudes with the cutting-edge turbine rotor nacelle assemblage.
Building Tower Designs
Lattice, concrete, tube, and hybrid towers are standard tower designs. There was no physical static or fatigue investigation on the tower’s structural integrity while evaluating the optimum tower height for a given rotor diameter within the simulation.
A frequent misconception is that the Federal Aviation Administration (FAA) has imposed a 500-foot height limit on all wind turbine towers.
| Wind Turbine Tower Type | Benefits | Disadvantages |
|---|---|---|
| Lattice Steel Tower | Greatest strength Less affected by wind Modular design | Lengthy on site construction time |
| Concrete Tower | Enhanced longevity Fewer maintenance costs Modular design | Longest installation time Difficult to transport sections |
| Tube Tower | Simple on-site installation Lowest total cost of ownership | Most affected by wind |
Lattice Steel Towers
Welded steel profiles are used to construct lattice towers. The truss action and more enormous base dimensions aid in more successfully resisting applied loads. Furthermore, the open tower reduces wind loads on the structure. The disadvantage of this kind of wind tower is the hefty on-site costs. Little tower sections are inexpensive to produce and transport to the location.
Concrete Tower
Concrete towers provide the critical advantages of enhanced longevity, fewer maintenance costs, and a modular design that can be adapted to practically any turbine machine.
These towers can be subdivided in practically any direction to facilitate transit. On the other hand, Concrete towers require a lengthier on-site construction depending on the assembly method.
Tubular Steel Towers
Most utility-scale wind turbines are mounted on top of a tubular steel tower. Tubular towers are constructed from two to ten steel rolled tower sections varying in diameter from 1.5 to 5 m. These towers are conical, with the tower’s base becoming smaller as it approaches the top. The tower parts are typically 20-30 meters long with flanged ends that enable simple bolted connections, considerably reducing on-site assembly.
Stronger Wind Power
When it comes to wind turbines, more power generation is unquestionably better. The greater the radius of the rotor blades (or the diameter of the “rotor disc”), the more wind the blades can convert into torque to power the hub’s electrical generators. More torque equates to more power.
Simply put: wind turbines can generate more electricity by increasing the rotor diameter.
Due to economies of scale, wind energy businesses are pushing for complex to build, larger rotor blades. More extraordinary aerodynamic efficiency results from more extensive and longer turbine blades. By producing greater power in a single turbine, less energy is lost when transferred to the transmission system and the electrical wind generator.
Most turbines will typically not operate in high winds, but they must resist these events without structural damage. When hurricane-force winds arise, the turbine’s blades are pitched against the wind to keep them spinning considerably slower, avoiding damage while providing enough electricity to keep critical safety systems operating.
Steel as Perfect Material Structure
Steel makes up most of the wind turbine’s significant components. In addition, steel offers excellent corrosion protection, a sturdy and dependable technique to seal towers, and a solution for more giant and more efficient wind turbines.
Steel is strong enough to keep the turbine’s blades in place while rotating and providing a sturdy nacelle frame and equipment. The nacelle can weigh up to 300 tons and requires robust steel to operate safely. In addition, it contains high-value steel, such as electrical steel, which aids in energy conservation. Steel towers look like guy wire anchors on television transmission towers or free-standing microwave relay towers.
Pros and Cons of Taller Towers
Taller towers that reach more than 100 meters fuel the demand for innovative engineering solutions. As a result, several companies are researching novel tower designs. The significant ideas rely on the basic tubular steel tower concept. However, other alternative design concepts incorporate composite steel and concrete towers.
Tall towers present technical hurdles, and structural engineering considerations become complicated.
Pros of taller wind turbine towers
Generally, taller tower allow for us to capture more wind energy, since wind is blowing faster at higher elevations.
Levelized Cost of Energy
More giant capacity turbines drive lower LCOE by spreading per-turbine fixed costs—whether upfront capital expenditures or operating expenses.
Higher Wind Speeds
Taller towers support turbines to access higher wind speeds, resulting in higher capacity factors. Finally, larger rotors increase energy capture and capacity factors when combined with a decrease in specific power.
Wind Performance
Previous research has shown that taller towers and larger rotors can improve wind power plant performance by increasing capacity factors. Higher capacity factors enable economic wind development in low wind speed areas.
Market Value
Taller turbines have a higher “market value in wholesale electricity markets,” particularly in places with higher wind penetration levels.
Scale Benefits
Taller wind turbines provide:
- Three smaller-scale benefits.
- Mainly cheaper electric transmission costs.
- Lower system balancing costs.
- Lower financing costs.
Cons of taller wind turbines
Taller wind turbines also have some negatives, many we may not have even experienced due to the relatively young age of the technology.
High Turbine And Rotor Speed
When wind speeds exceed 50 mph, the turbine and rotor reach Overspeed (>24 rpm). This causes high loads, and the entire system may fail.
E-stop
The short/hard stop produces a shock load spectrum on the structure. It results in a significant dynamic impulse load to the system, resulting in considerable lateral deflections.
Long-term soil fatigue
This stress causes the tower-structural system to weaken and the rotational stiffness to decrease over time. It causes the structural period to prolong (the frequency to shorten), eventually leading to a resonance problem.
Weld Fatigue Failure
Steel welds that crack due to residual tensions built up over time. The tower’s buckling capacity is lowered, and eventually, the tower shell falls.
Blade failure
Occurs when blades are overstressed as a result of fatigue, wear and tear, excessive vibration, and collapse caused by external stresses
New Generation of Air Wind Turbines
A new class of wind energy converters known as Air Wind Energy Systems has been developed as one of the revolutionary methods for producing power from renewable resources. This new generation of devices uses tethered wings or airplanes to reach winds flowing at atmospheric layers than standard wind turbines cannot get.
Additionally, these air wind turbines as paired with air tower kits. To the best of our knowledge, these are cost-effective and user-friendly tower kits wire structure that allows for the use of lightweight tubing while providing sufficient power for all but hurricane circumstances.
Air Breeze Turbines
Air Breeze provides reliable energy under adverse weather. This field-proven equipment is designed for battery-charging applications from coastal to desert to Arctic conditions. It provides the energy required for communications, offshore structures, sailing, and remote monitoring, to mention a few applications.
Air 40 Turbines
A brand new Air 40 is quieter, more efficient, and precise design designed to deliver more power at lower wind speeds than other wind turbines in this class. The Air 40 turbine is the world’s most popular small wind turbine, the next generation of air turbines with over 100,000 units sold in 120 countries.
Air 30 Turbines
The Air 30 is based on what makes AIR one of the best-selling small wind turbines globally. Previously, the new Air 30 was only found in megawatt-class wind turbines. The AIR 30 uses new microprocessor-based technology to improve performance, battery charge capacity, and reliability. In addition, the flapping noise of the machine is reduced.
Conclusion
Wind energy systems are being integrated into taller tower building designs, which look to be ideally adapted to the technology due to their high wind speeds. The increased height of the tower can significantly improve efficiency and create substantially more electricity. Ultimately, taller towers provide a more extended range of wind energy resources than shorter ones.
Additionally, it has been proven that steel has been used in most turbine components to increase strength and longevity in taller wind turbine tower industries maximizing its integrated engineering and design.
This skyscraper will transform wind energy and promote its use in cities. Taller wind turbines are not only a future monument to our metropolitan landscape, but they are also created to emulate nature’s beauty and encourage environmental sustainability.