Wind power is one of the fastest-growing renewable sources that works well at scale, but it isn’t perfect. A wind turbine’s massive size and moving parts make them challenging to roll out because of the space they take up, as well as maintenance. But what if we could scale down that power to something that could fit on your roof? And be self-contained with smaller moving parts … or maybe no blades or moving parts at all? Let’s look at some future alternatives for harnessing wind power.
It’s not hard to see that, along with solar, wind power has been a major player all over the world in lowering our carbon emissions from fossil fuels. According to the latest Global Wind Report, 93 GW of new global wind power capacity was installed in 2020, with the U.S. and China leading the way. Currently, 743 GW of wind power capacity is installed worldwide, making it the green power source with the most decarbonization potential per MW. It’s helping to avoid over 1.1 billion tons of CO2 globally. But, wind turbines aren’t all good. 1
As I mentioned in a previous video, wind turbines have several downsides. Harnessing wind requires high upfront costs, and the energy generation isn’t as effective for individual homes, or small scale installations, as they are at large scale. The construction of wind farms has also had an impact on wildlife. While they do kill a good number of birds and bats every year, when you look at those numbers in context it’s blown a little out of proportion. The U.S. Fish and Wildlife Service estimates that between 140,000-500,000 birds die at wind farms each year. Compared to the 2.4 billion birds that are killed in the U.S. each year by domesticated cats, or the 1 billion birds that die from flying into windows.2 3 4 There are simple solutions that are proving to be effective for that, like just painting one of the blades black.
But there’s also the fact that turbines have a lot of moving parts, like the gearbox, which require a decent amount of maintenance. They need to be checked two to three times a year. And this is where solid-state wind power arrives on the scene. 5
In 2013, researchers at Delft University of Technology in the Netherlands removed the need for moving mechanical components and created EWICON, which stands for Electrostatic Wind Energy Convertor, kicking off the development of the ion wind generator concept. While it’s still very much in development, it provides significantly lower maintenance costs, less wear and tear, and no noise issues. 6
And how it works is kind of fascinating. EWICON utilizes wind to create a flow of charged particles through the air that can be tapped into to produce electricity. In this case, water droplets are used to hold a positive charge and, when the wind blows them, this movement of the droplets produces electricity that can be transferred to the grid. 7
A prototype of the EWICON is installed at the Delft University of Technology.
An obvious downside of this idea is the reliance on water to carry the charge. You’d need a water line run to installations and it wouldn’t work at freezing temperatures. But there’s another idea called the Solid-State Wind-Energy Transformer (with the unfortunate acronym … SWET) developed by Richard Epstein. His approach is very similar to what the Dutch developed, but instead of using water his concept uses ionic currents to produce electricity. This process is called “electrohydrodynamics”. 8
Richard Epstein described the prototype as a series of 55 parallel aluminum wires strung between two 8.5-meter tall wooden masts, separated by about 8 meters on a flat roof, and all the wires were electrically isolated from the masts. In the prototype there were two kinds of wires: attractor wires, which were plain wires, and emitter wires that contained small tufts of 7-micrometer diameter carbon fibers attached about every 15 cm. When small negative currents flow through the emitter wires, the tufts create a coronal discharge, releasing negative ions into the air. It’s not that different from ionic air purifiers that were all the rage in the early 2000’s … if you remember the ionic breeze … I’m still trying to forget those commercials. So just like the EWICON concept, the wind blowing past the wires 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. 8
The prototype developed by Epstein has just 1/20 of a watt of power, but it’s just a prototype to prove the concept and it’s still at the first steps of its development.
Utilizing the same principles of EWICON, the Dutch Windwheel Corporation is developing a 160-180 meter high future landmark in Rotterdam. It looks kind of like a gigantic donut. The hole in the center will be putting this solid state energy generation to work. The structure’s also intended to pull together multiple eco-friendly technologies, including rainwater capture, wetland water filtration, and solar energy. Not to mention apartments, a hotel, and a sky bar. Who doesn’t love a good sky bar? It’s expected to be built sometime between 2022 and 2025. 9
Now, as cool as that tech is, it’s all still very much in the early phases of development, but there are some other technologies that could be hitting the residential and city market sooner. Another type of wind generator without moving parts has been developed by Vortex Bladeless. But warning … it looks a little weird. This Spanish company has developed a vortex induced vibration resonant wind generator, which is based on the principle of Vortex Shedding. The generator is built with the shape of a cylinder, producing electricity through an alternator system when the mast oscillates. The bottom of the rod is firmly attached to the ground, but the upper portion is unconstrained and able to vibrate.
The structure is built with materials used in traditional wind turbine blades, using resins reinforced with carbon and/or glass fiber. Bladeless wind turbines get rid of the mechanical elements that can suffer wear by friction. 11
But how does this wiggling, vibrating column produce energy? Well, to understand this we’ll need to jump a little bit into the world of fluid mechanics.
As wind passes by a blunt body, the flow is changed, producing a cyclical vortices pattern known as vortex shedding. Imagine placing a cylinder partially submerged into running water. If the water is moving too fast or too slow, the vortices that form around the cylinder are chaotic. But if the speed of the water and frequency of the object are matched, the vortices form more consistently and will exert force on the cylinder causing it to move.
Every body or structure has a natural frequency. If the frequency of these vortices is close enough to a body’s structural frequency, it starts to oscillate, resonating with the wind. This is also known as Vortex Induced Vibration (VIV). You’ve probably seen or heard of the ramifications of this effect on bridges that weren’t designed properly, like the Tacoma Narrows Bridge. Engineers and architects design bridges and skyscrapers to avoid this effect. They design structures to have different resonant frequencies from the wind’s resonant frequency.
But Vortex Bladless is doing the exact opposite in order to put vortex induced vibration to work. Vortex’s mast geometry is specifically designed to achieve maximum performance with typical wind speeds. To convert these vibrations into electricity, Vortex Bladeless turbines utilize an alternator system made by coils and magnets, that can adapt to the vortex dynamics with no gears, shafts or rotating parts. This design provides reduced maintenance and rules out the need for greasing.
This magnetic confinement design acts as a “tunning system,” so it can increase the stiffness of the system according to the deformation that the wind causes. It’s basically adjusting and synchronizing its natural frequency to match the wind’s frequency. 11
Today Vortex Bladeless turbines harvest about 30% of the area covered by the blades of a traditional 3-bladed wind turbine of identical height; this is called swept area. The bottom line: vortex technology is less power efficient than the traditional 3-blade turbines since the power production is proportional to the swept area of a wind turbine. On the flip side, a smaller swept area allows for more bladeless turbines to be placed in the same area, making up for that power efficiency gap. Running at low to medium wind speeds, it’s able to generate the same power for less cost. It’s about 45% cheaper than a traditional 3-blade wind turbine.11 12 13
The Vortex Tacoma, which is 2.75 meters high, has an estimated rated power output of 100 watts, and the company expect Vortex Tacoma models to have a similar price to medium-high production solar panels.
Now, getting closer to the residential market for wind turbines, Savonius turbines have been gaining popularity. These wind turbines are simple drag-type devices that consist of two or three scoops. 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 than other lift-type turbines of a similar size. However, they are cost-effective, can operate regardless of the wind direction, the blades in the turbine need no mechanism to alter the angles, and they’re more bird and bat friendly than conventional 3-bladed turbines. 15
With this idea in mind, the Iceland-based company Icewind has been manufacturing Savoniuos turbines for residential and commercial applications. Their CW100 model, sold as THE FREYA in the U.S., is designed to deliver long-lasting performance, with little or no maintenance for over 25 years. This 1.5-meters high turbine is able to withstand wind speeds up to 130 mph (60 m/s) and generate up to 600 watts. 16
The company sells each turbine for $3,200 and a complete on-grid system with a 1.5 kilowatt inverter for $4,180. In the U.S. the cost of a set of solar panels to produce the same 600 watts would be around $1,932. 17 The turbine is a bit more expensive, but you also get the potential for producing power during the night.
But the innovations on wind power don’t stop here. Halcium, a startup based in Salt Lake City, Utah is hoping it’s portable wind turbine will be the next big innovation in green energy. The company’s been developing what they call a PowerPod, which is a small-scale wind turbine designed specifically to work in towns and cities. 18
The PowerPod does have a blade system, but it’s completely contained entirely within the stationary shell, making it safe for kids, pets, and wildlife since it has no external moving parts. The wind generator’s shape can collect wind from any direction, changing directions, or even multiple directions at once. A 1kW wind turbine would produce up to three times more power than a normally mounted turbine of similar size and swept area. This extra power comes from the advanced blade system of the pod that boosts up wind speed by 40%. To make this happen, the PowerPod takes air and funnels it into a smaller exit, which speeds it up before hitting the internal blade. 18 It reminds me a little bit of a Dyson vacuum cleaner’s vortex cyclone.
Much like some of the other turbines I’ve talked about, the interesting angle with the PowerPod is its capability of being either connected to a building on its own, or paired with solar to diversify your power sources. And the PowerPod’s design means it can be installed anywhere: house rooftops, public buildings, fences, etc. 18
Nick Hodges, the founder of Halcium, created a map showing the average daily power generated from a 1kW PowerPod compared to a 1kW solar panel system in different parts of the world. In most cities, the PowerPod could perform equal or greater than a conventional 1kW solar panel system. A big reason for this is due to its 24/7 operation, while solar is limited to daylight hours, and has lower production on cloudy or rainy days. 19
Although the PowerPod isn’t for sale quite yet, and the specifications aren’t well-known, it’s an interesting idea to bring wind generation in a more flexible package closer to our homes. The PowerPod will most likely be available towards the end of 2021. 18
As we can see, wind power generation isn’t limited to traditional 3-bladed turbines we’re used to seeing everywhere. These innovative, small-scale, lower-maintenance wind generators with no or hidden moving parts hold a lot of promise. In the coming years we’ll probably be seeing more of these alternatives on tops of office buildings and even homes. I think I’d opt for the PowerPod over the wiggling column, but I won’t be too picky.
- Global Wind Report 2021 ↩︎
- The Realities of Bird and Bat Deaths by Wind Turbines ↩︎
- The impact of free-ranging domestic cats on wildlife of the United States ↩︎
- Birds and Windows0 ↩︎
- How often do turbines require maintenance? ↩︎
- EWICON bladeless wind turbine generates electricity using charged water droplets ↩︎
- Windenergy convertor EWICON animation, TU Delft ↩︎
- A solid-state wind-energy transformer ↩︎
- DOEPELSTRIJKERS – DUTCH WINDWHEEL ↩︎
- Meet the Dutch Windwheel ↩︎
- Vortex Bladeless – How it works ↩︎
- No blades! A pole-shaped wind turbine, Vortex Bladeless, generates power by shaking. ↩︎
- Wind turbine design ↩︎
- Vortex FAQs EN ↩︎
- Savonius wind turbine ↩︎
- Icewind – Residential ↩︎
- Solar panel cost in 2021: what price for solar can you expect? ↩︎
- PowerPod ↩︎
- IS THIS THE ‘SAFEST, MOST POWERFUL WIND TURBINE IN THE WORLD’? ↩︎