It’s really beginning to feel as though the problem of climate change is a huge boulder rolling down a steep hill, and we have the Sisyphean task of trying to reverse it. While we definitely need to switch as much of the planet over to clean, green energy as soon as possible, the deployment should be strategic. You know, solar panels in sunny places, and wind turbines in windy places. And for the most part, we’re already doing that.
In the meantime, there are also natural disasters to deal with, some of which are worsened by climate change. Eastern and Southeast Asian countries are frequently under the threat of typhoons that bring strong, turbulent winds with them. Once the storms pass, they leave large swaths of lengthy power outages in their wake.
Studies have shown that these storms are gaining strength over the years, leading to more frequent disruption of existing power systems in those areas. Wind power is the ideal solution where storms have come through and knocked out traditional power delivery all over a region. As long as the turbines themselves can stand up to the challenge, they can be used to power micro-grids when other delivery is knocked out.
Bring On the Typhoons?
Unfortunately, the conventional three-bladed wind turbines you see dotting the plains can’t stand up to the awesome power of typhoons. But vertical axis wind turbines can. Though they have been around for many years, they may have finally found their niche.
A Japanese startup called Challenergy wants to face the challenge of typhoons head on. They’ve built a vertical axis wind turbine that’s built to not only to withstand typhoon-level winds, it’s designed to make the most of them. Instead of horizontally-situated blades arranged like spokes or flower petals, these turbines have vertical cylinders that collect wind by harnessing the Magnus effect.
Put Some Spin On It
If you’ve ever put spin on a ping pong ball, or pitched a curve ball, you’ve put the Magnus effect in motion. This observable phenomenon was first recorded by German physicist Heinrich Gustav Magnus in 1852.
Magnus noticed that that path of a spinning object is deflected by the pressure differences in the air around it that are caused by the spinning. This deflection in the path from the expected arc would not be present without the spin, and so this deviation from the norm is now known as the Magnus effect.
Challenergy’s turbines feature three cylinders that are driven to spin with a motor. The motor induces the Magnus effect on the wind around the cylinders, and rotates the turbine to generate energy.
Like we said, vertical wind turbines themselves are nothing new. They’ve been used to power ships and airplanes for decades, and we’ve even covered a few DIY versions. For this application, though, the magic is in the high-speed winds of typhoons.
Besides being long-term usable in typhoon-infested regions, Challenergy’s turbine has several advantages. The cylinders can adjust to any wind direction, and there are flaps on the cylinders that can be adjusted to program the level of Magnus effect going on. They move ten times more slowly than traditional turbines, but as a result, they’re also less noisy and likely less of a threat to birds.
And technically, no, they’re not as efficient as regular three-bladers are because they require a ~10% energy investment to move the motor. When the typhoon hits, that’s when the payoff comes — the citizens can have emergency power immediately and don’t have to wait days or weeks.
Does Size Matter?
At 20m tall, Challenergy’s turbines are also much shorter than the 80-meter tall towers of traditional turbines in Japan. You can see the difference in the drone footage below.
Challenergy’s turbines generate a maximum 10 kilowatts compared to the maximum 3 megawatts put out by propeller turbines. But they don’t really need to be tall to harness typhoon winds or to be of great use to people. Even so, the company is planning to make a 50-meter tall version that will be capable of putting out 100 kilowatts.
A Challenergy turbine installed in Ishigaki, Okinawa, Japan has already had the chance to prove its mettle. Typhoon Mitag hit Japan in October 2019, and the turbine’s sensors recorded wind speeds close to 100MPH (160km/h), still safely below the 156MPH (251km/h) the company says they’re designed to withstand.
Challenergy founder and CEO Atsushi Shimizu was inspired by the 2011 tsunami that caused three meltdowns at the nuclear plant in Fukushima. Since then, the Japanese government has begun to turn away from nuclear power. Shimizu believes that the power generated from a single typhoon could power Japan for 50 years, though it’s unclear how many turbines that would take or how they would store the energy. Liquid air batteries, perhaps?
For now, the government of the Philippines have signed on to buy seven of Challenergy’s turbines in order to make micro-grids with solar and diesel generators. Time will tell, and we’re anxious to see how the country fares once they’re up and running.