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A vertical Axis wind turbine that doesn't need the prevailing wind! How do they do that?

Dave Borlace presents a counterintuitive proposition: that the most valuable wind energy of the future may not come from towering giants chasing the horizon, but from small, unobtrusive devices harvesting the chaotic air pushed aside by passing cars. This coverage is notable not just for its technical details, but for reframing urban infrastructure—specifically motorway lamp posts—as a dormant power grid waiting to be activated. For busy readers tracking the evolution of renewable energy, this piece offers a tangible, near-term alternative to the massive, land-intensive projects that often face public resistance.

Rethinking the Wind Resource

The core of Borlace's argument rests on a shift in perspective regarding where wind energy exists. He challenges the conventional wisdom that wind turbines must be placed in open fields or offshore to be viable. "Generally speaking, the grown-up versions all have a very tall mast and three blades attached to a central nay cell," he notes, contrasting these massive horizontal axis turbines with the vertical axis models that are the focus of this analysis. The distinction is crucial: while traditional turbines require a "yaw system" to mechanically turn into the wind, vertical axis turbines can capture energy from any direction, making them uniquely suited for the turbulent, multi-directional airflow of a city street.

A vertical Axis wind turbine that doesn't need the prevailing wind! How do they do that?

Borlace highlights a specific British startup, Alpha 311, which has moved beyond the realm of backyard DIY projects to create a commercial solution. The company's insight was to stop trying to build new infrastructure and instead retrofit what already exists. "Having researched existing studies of the potential for roadside turbines, they realized that the focus was usually either on placing turbines right at the top of lamp posts where they wouldn't get any benefit at all from oncoming traffic or building entirely new infrastructure in addition to the hardware that was already there," Borlace writes. This reframing of the problem—viewing existing lamp posts as the ideal mounting point rather than an obstacle—demonstrates a pragmatic approach to scaling renewable energy.

Unlike horizontal axis turbines, Alpha 311's turbine doesn't need a bulky system because it can use air flow from any direction.

The technical execution described is equally compelling. The turbines are designed to be lightweight, weighing between 3.5 and 8 kg, and are constructed from durable recycled composites. They utilize a static magnetic stator and a stainless steel rotor, eliminating the heavy gearing systems that often plague traditional turbines. "The blades themselves will be partly shrouded to ensure the optimum energy harvesting from air flows in both directions and to avoid any canceling out interference," Borlace explains. This design choice addresses a common failure point in vertical axis designs, where opposing forces can cancel out energy generation.

The Physics of Wasted Air

Perhaps the most striking claim in the piece is the assertion that vehicles generate a significant, untapped energy resource simply by moving. Critics might argue that extracting energy from vehicle wake violates the principle of conservation of energy, effectively increasing the fuel consumption of the cars themselves. Borlace anticipates this skepticism but counters it by emphasizing the nature of the airflow. "Those vehicles are all punching a hole in the air and causing air flow around them regardless of whether there's a turbine or a building or anything else at the side of the road," he argues. "And that air flow is essentially just wasted energy."

The data presented supports the viability of this approach. Borlace cites testing by the Institute of Thermofluids in the UK, which showed that even without prevailing wind or traffic between 10 p.m. and 7 a.m., the turbines generated more power than anticipated. "Typical average motorway traffic speeds of 60 mph produce a residual air flow of 5.4 m/s, which is about 12 mph," he notes. At this speed, a single turbine can generate just over 2.5 kW with a 30% efficiency rate. When scaled to a 5.4-mile section of the M2 motorway, the potential output is substantial: over 860 megawatt-hours annually.

This potential extends beyond just powering the streetlights they are attached to. "The space allocated for the magnetic stator also houses a center array for data collection from sensors that can be mounted onto the lampost which means Alpha system can also monitor air quality, weather conditions and traffic statistics," Borlace points out. This transforms the turbine from a simple generator into a node in a larger Internet of Things network, adding a layer of urban intelligence to the energy generation.

Scalability and Future Applications

The piece concludes by broadening the scope of application, suggesting that these compact turbines could solve energy challenges for telecommunications infrastructure. "A typical 5G mast uses about 7 kwatt hours of energy every day. One of these turbines installed on each of those masts will provide very nearly all the power they need, removing a significant load from our national grids," Borlace writes. This application is particularly relevant as 5G networks expand globally, creating a massive new demand for decentralized power sources.

The argument also touches on the potential for domestic use, suggesting that pairing these turbines with solar power could help alleviate fuel poverty. "That solar system would pull a lot of people, even here in the UK, out of fuel poverty," Borlace asserts. While this is a more speculative application compared to the motorway installations, it underscores the versatility of the technology. The author acknowledges the early stage of development, noting that "companies like Alpha 311 and so many others all over the world are all working towards the same basic end goal, which is to develop working alternatives to the existing dominance of fossil fuels on our electrical grids."

Alpha 311's installations will never replace onshore or offshore wind turbines, and they're not designed to. But they can provide a very valuable complimentary power source that'll improve the diversity of renewable energy inputs onto those grids.

This acknowledgment of limitations strengthens the piece's credibility. Borlace does not present this as a silver bullet but as a necessary component of a diversified energy portfolio. The focus on complementing existing infrastructure rather than replacing it is a strategic move that aligns with the practical realities of grid integration.

Bottom Line

Dave Borlace's analysis effectively shifts the conversation from the scale of energy generation to the efficiency of resource utilization, proving that wasted kinetic energy in urban environments is a viable target for renewable technology. The strongest part of the argument is the rigorous data backing the specific application of traffic-induced airflow, which moves the concept from theoretical physics to engineering reality. However, the biggest vulnerability remains the long-term durability of these devices in high-traffic, high-vibration environments, a factor that will only be fully understood once the initial production runs are operational. Readers should watch for the performance data from the upcoming installations at the O2 center and in New York, which will serve as the critical proof of concept for this approach.

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A vertical Axis wind turbine that doesn't need the prevailing wind! How do they do that?

by Dave Borlace · Just Have a Think · Watch video

I'm guessing you probably don't need me to give you any clues about what this thing is. Admittedly, you don't see too many of them with lurid green blades or any of this nonsense sticking out the back, but it's a wind turbine, isn't it? And its bigger brothers and sisters are now a fairly regular sight across large parts of many of the countries where you good folks are watching this from. Generally speaking, the grown-up versions all have a very tall mast and three blades attached to a central nay cell with a heavyduty gearing system inside to translate the rotational kinetic energy of the blades into useful electrical energy via a generator.

They form part of a subcategory called horizontal axis wind turbines or horts. But they're not the only way you can get electrical energy from wind. There's a whole other subcategory called vertical axis wind turbines or vaults. These things are extremely popular among the DIY enthusiast fraternity, many of whom have rigged up rudimentary versions in their backyards or gardens to provide useful power for their homes.

Now, a new company has taken the basic concept of vertical access turbines to create a commercial model that's designed to work even when there's no prevailing wind. So, how do they do that? Hello and welcome to Just Have a Think. The science of wind turbine dynamics and efficiencies is pretty much an entire field of technical expertise in its own right.

There have been all sorts of different approaches and designs over the years, all aimed at achieving the optimal overall performance. Vertical axis turbines or vorts tend to fall into one of two sub subcategories. Savonius turbines like this one or Darius turbines like these. And you'll find dozens of very entertaining DIYers on YouTube who've chopped up oil drums and various other articles to produce their own homemade energy generators.

When it comes to grids scale commercial wind turbines though, there are various reasons why horizontal axis turbines have generally been favored over vertical axis. At those sorts of enormous dimensions, early development prototypes of vault systems proved less efficient. And in the days before we had new fangled composite materials, vaults also proved less reliable as well with turbine blades tending to shear off with the constant changing directional forces from the wind. In-depth comparisons between Horts and Vorts are beyond the ...