Environmental energy companies have higher and higher goals. From inflatable large-scale wind turbines in the air to small for gliders that are connected to generators at the ground – several efforts at airborne energy solutions are winning the trust of investors. We on Earth have the potential to harness the renewable energy above us.
A problem with wind power as it exists today is that the wind does not always blow where the wind turbines are. Thus, wind power is an unreliable source of energy today. But higher up in the atmosphere it is a different story. Already at a few hundred meters altitude , the wind is more or less constant. The wind is smoother, but above all it blows more. There are no clouds to affect the wind strength so there is no friction affecting the wind strength and direction as it is near the soil surface. Far up in the atmosphere are also jet streams consisting of large masses of air that are constantly moving at high speeds. In an analysis published in the scientific journal Energies, it was concluded that on a theoretical level that jet streams could cover the annual global energy demand 100 times over.
The only question is: how do we get access to these nearly unlimited resources? The jet stream at several kilometers altitude is obviously difficult to access. But so far up we do not have to go to reach favorable conditions. Therefore, many researchers and companies are keeping their eyes on the sky- while fossil energy hunters burrow deeper into the soil for gas and oil.
Several corporate plans now show that airborne solutions for wind power are emerging as concrete investment opportunities for clean and safe electricity develop.
The advantages of air born turbines
There were some recent plans unveiled to hoist a large gas-filled construction – with a wind turbine in the middle – to 300 meters, which is approximately the height of the Eiffel Torns. But the project will not be implemented in Paris, but in remote Alaska. The idea is that Altaeros Energies airborne turbine (BAT Buoyant Airborne Turbine) in a first step, will supply electricity to a dozen homes that currently do not have a proper connection to the power grid. The company’s environmental technology was awarded the ConocoPhillips energy prize in 2011.
The structure itself looks like a large inflatable letter O, but with stabilizing fins and a rotor blade in the middle. The energy is transferred through a cable to a generator on the ground. On board there is a sensor that allows the turbine to operate independently; for example it may adjust its position by wind or land if the weather gets too hard. According Altaeros Energies the result is wind energy with about three times higher capacity than a conventional wind turbine.
Another important advantage of this idea is that it can be transported and assembled quickly without using cranes and other heavy equipment. Successful tests have also shown that the structure can be used for example to provide connectivity to wireless Internet in its vicinity. This will make the solution even more interesting for the intended users in places like Alaska, but also on islands, military bases, remote mining or agricultural operations and in disaster areas.
Wings imitate conventional windmills
Another idea for airborne wind power utilizes principles from a standard wind turbine, but skip its large solid cemented structure. Instead, a kind of wing like kite is anchored to the ground via a cable. This flying wind turbine (AWT , Airborne Wind Turbine), is built by Makani Power, flying around in vertical loops in a circle up to a height of about 250 meters.
Interest in the technology is great, and in 2013 was Google bought Makani Power and integrated it into the company’s development arm Google X, otherwise business includes the development of autonomous vehicles.
The flying wind turbine consists of a relatively simple construction. The consumption of materials is estimated to be approximately one-tenth compared to conventional wind turbines and cost half as much. To use high altitudes makes it cheaper to install in places that are unsuitable for traditional land – or sea-based wind turbines. Makani Power believes that the current structure has shown that their flying technology solution holds. Therefore, the next design on a commercial scale – a larger variant – will generate enough energy to power 300 homes.
As with many other innovative environmental technology solutions, it is making them profitable to commercialize that is the biggest hurdle. But this development underscores a trend in wind energy – more airborne options.
The idea of using high altitude winds as a source of useful energy already existed in the 1800s. But only recently have companies dared to invest properly. Wind power manufacturers today have gained traction in the U.S. but also in Europe where Germany, the Netherlands and Italy have recently been at the front. Perhaps most importantly, businesses and strategic players need to become more numerous, and their spread across the world – more and more are seeming keen to get involved and invest in these new technologies.
This article was published in May 2014