This episode is brought to you by Brilliant ... click the link in the description below.
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.
I'm Matt Ferrell ... welcome to Undecided.
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.
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. 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. [^maintenance_checkup]
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.
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.
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".
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.
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.
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.
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.
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.
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.
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.
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. 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.
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. 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.
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.
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.
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.
But if you'd like to understand more about how the Vortex Bladless design even works,
or how the ions flow in the solid state designs I talked about, you can learn a lot from the
Electricity and Magnetism course and Brilliant. It helped me get a better sense for how everything
related to electricity or magnetism starts with a charge. And how ions can flow across
different elements like saltwater.
But even if you don't get charged up learning about electricity (I love a good dad joke),
they have over 60 courses including topics in computer science, physics, and mathematics.
They've got something for everybody.
All of the concepts are taught through fun and interactive challenges to help you understand
the "why" of something ... not just the "how." It helps to develop your intuition, which
is my favorite part about Brilliant and taps into the way I learn.
Go to www.brilliant.org/Undecided to sign up for free. The first 200 people will get
20% off their annual premium membership. Thanks to Brilliant and to all of you for supporting
the channel.
So would you want something like a PowerPod for your home? Jump into the comments and
let me know. If you liked this video be sure to check out one of the ones I have linked
right here. Be sure to subscribe and hit the notification bell if you think I’ve earned
it. And as always, thanks to all of my patrons and a big welcome to new producer Serverless
Nomad. Thanks for watching. I’ll see you in the next one.