The New Kinds Of Wind Turbines That Function Without Blades
May 28, 2024 7:00 am
The New Kinds Of Wind Turbines That Function Without Blades
5 min read
Wind energy has been around for decades and has helped us produce clean electricity using a resource which is naturally available. Wind energy also works almost everywhere and is highly efficient.
But wind turbines still do take up a good amount of space and are not very functional within cities due to their size. However, there is a new wind turbine technology which seeks to eliminate these problems while still keeping the benefits of wind energy.
Wind turbines use air foils to increase lift and decrease drag by causing air to flow around it due to its feather shape. This causes pressure, which causes the rotor blades of the turbines to turn, which powers the generator, which then produces energy.
The new proposed air foils are bladeless, motionless, and stand vertically opposite one another allowing for air to pass between them, similar to the rear wings on a race car. This creates a low pressure zone where a pipe sucks wind and transports it to a turbine in a closed tube under the motionless turbines.
These bladeless turbines were developed by American company AeroMINE. The company claims that due to the lack of moving parts, their wind turbines require less maintenance. They also say it can operate at 8 km/h compared to the 15 km/h minimum speed requirement for traditional turbines.
The company also claims that a single AeroMINE wind turbine can produce the same amount of power as 16 solar panels. They rate their turbines at 5kW and estimate that each one can produce 14,3MWh of electricity a year. The typical 21 panel rooftop home solar system produces about 5kW and 4,5MWh a year.
The company says their product targets large flat rooftop buildings and that in theory, there should be 20-40 turbines in single file on the edge of a roof, spaced 4,6m apart, facing the main wind direction. This would leave room for solar panels so that power could be produced on sunny and cloudy days. They go on to say that along with existing solar energy, their turbines can produce 100% of a building’s energy needs.
Advantages:
- Turbine is safe from human and animal interference
- Safe from extreme weather conditions
- Silent
- Takes up less space than traditional wind turbines
Disadvantages:
- Turbines are stationary and cannot rotate to face the wind
- Potentially cost compared to traditional turbines and solar
- Currently only suited for commercial use
The company claims that their wind turbines generate up to 50% more energy than other renewable energy alternatives at the same or lower cost while using less space.
Researchers at the Delft University in the Netherlands teamed up with architects to develop a bladeless wind turbine that produces electricity using charged water droplets. The result was EWICON (Electrostatic Wind Energy Convertor). It uses wind to create a flow of charged particles through the air that can be harnessed to produce electricity.
How it works
- The electric force of the field moves the water particle to the negative side of the electric field created by the turbine system.
- The wind pushes the particle to the positive electrode, increasing the potential energy of the particle.
- Increased energy is collected.
Advantages:
- System is cheaper to maintain than bladed wind turbines.
- Less wear and tear
- Can come in many different shapes and sizes
- Can be placed on water
- Can be placed in urban or suburban areas
- No noise pollution
Disadvantages:
- As water is required to transport the charge, the system would not function in sub-zero temperatures.
- Creation of charged particles requires careful insulation and heavy safety measures.
An EWICON prototype has been on the Delft University of Technology’s campus since March 2013. Rotterdam is proposing a ‘Dutch Windwheel’ for their city based on the EWICON technology. It will be a 160-180-metre-high bladeless wind turbine that will also serve as a landmark. It is also expected to use other eco-friendly tech such as rainwater capture, wetland water filtration and solar power.
The SWET (Solid-state Wind Energy Transformer) is another such bladeless wind turbine technology. It is similar to the EWICON turbine, except it uses ionic currents instead of charged water droplets to produce electricity. This method is known as electro hydrodynamics.
How it works
- A series of 55 parallel aluminium wires are strung between two 8,5m tall wooden masts, separated by about 8m on a flat roof.
- All the wires are electrically isolated from the masts.
- When small negative currents flow through the ‘emitter wires’, the tufts create a coronal discharge, releasing negative ions into the air.
- The wind blowing past the ions carries the negative ions with it, and the array gets a slight positive charge.
- This causes electrons to flow from the ground, which can be collected as electricity.
Spanish company, Vortex Bladeless, has developed a vortex induced vibration resonant wind generator.
How it works
- A cylindrical mast oscillates freely while on a fixed carbon rod.
- Vortexes of pressure form when wind passes around the structure.
- If the structure’s natural frequency is similar to that of the vortexes (which depends on wind speed), it begins to oscillate and harness energy.
The system can also adjust for slower and faster wind speeds to produce maximum electricity. Although Vortex’s bladeless turbines output less electricity than regular turbines, they also take less space, meaning more of them can be placed closer together in an area. The Vortex Tacoma is 2,75 metres high and outputs about 100 watts.
Advantages:
- Functional at a wide range of wind speeds
- Less maintenance
- Bird friendly
- Silent
- At about 45% cheaper than a 3-blade turbine
Disadvantages:
- Less energy efficient than 3-blade wind turbines
Savonius turbines are more geared towards the residential market. These turbines consist of two or three half-cylinders. Due to their curvature, the scoops experience less drag when moving against the wind than moving with the wind, which makes it extract less wind power. Icelandic company Icewind, has been manufacturing savonious residential and commercial application. One of their vertical axis wind turbines, the ‘RW100’, can operate with wind speeds of up to 209,22 km/h (60m/s) and generate up to 600 watts while lasting for 20 years. The turbine alone costs $3 200 (R5 4431,68) with the option of a complete on-grid system for an extra $980 (R16 669,70). The equivalent solar kit would cost around R16 800.
Advantages:
- Cost-effective (when scaled).
- Can operate regardless of wind direction.
- Operates in extreme conditions.
- Bird and bat friendly.
Disadvantages:
- High cost (at low scale).
American start-up, Halcium, developed a portable wind turbine called the PowerPod. Designed for towns and cities, the PowerPod has blades but are contained inside the cylindrical structure. The device can collect wind from all directions, even at once. Its advanced blade system increases wind speed by 40% when the wind is taken in, sort of like a vacuum cleaner vortex. Founder of Halcium, Nick Hodges, created a map showing the average daily power generated from a 1 kW PowerPod compared to a 1 kW solar panel system in different part of the world. In Cape Town, the PowerPod performed more than 3 times greater than a conventional 1 kW solar panel. A big reason for this, could be its 24/7 operational ability. The PowerPod is not in production yet and does not have solid power generation figures.
Advantages:
- No exposed moving parts, making it safe for people and animals.
- Silent
Disadvantages:
- Not yet fully developed, thus not available for sale yet.
Although these technologies may sound innovative and exciting, all of them are yet to hit the market at scale and are thus yet to be tested in market conditions.
What do you think of bladeless wind turbines? Are they the future of renewable energy? Share your thoughts by replying to this email!
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