For many decades, society has been searching for a new, clean, sustainable source of energy. We have been well aware of the negative consequences that our extreme use of fossil fuels has caused. Because of this, we have poured money and research into a large variety of possible alternate energy sources. Some of these new energy sources we derive from the Earth and nature around us, such as wind energy. However, there are still drawbacks with the conventional wind turbine. In order to produce more power, wind turbines are growing, both in size and cost. They are larger, heavier, harder to maintain and run, and are confined to only a certain number of places around the world. However, new technology being produced by several companies around the world, such as Makani Power and KiteGen, have a new take on harnessing wind energy. These companies utilize specially designed kites in order to harness the energy of wind at high altitudes. This method is not only cheaper than a conventional wind turbine, but it also has the potential to be much more efficient. Experts state the high altitude kites could have the potential to solve the difficult challenge of bringing electricity to many parts of the globe that do not have enough of it . I believe that this could be a large step forward in the search for a clean, renewable, and sustainable energy source.
Currently, the large majority of wind energy comes from the conventional wind turbine. Despite the immense power contained in the wind, only three percent of the world’s power comes from wind energy . Wind turbines are at a plateau. They have grown taller, heavier and more expensive while producing little difference on the output of energy. Alternative outlets for wind energy must be explored, and high altitude kites is one of the more promising of these new outlets. Possibly the biggest problem with wind turbines is their altitude. A common wind turbine reaches a maximum altitude of 80 meters. This altitude does not come near tapping into the potential that is in higher altitude wind. On the website of KiteGen, a company that produces and runs high altitude kites, they state, “Wind total power is estimated between 1,700 and 3,500 TeraWatts; by comparison, the whole mankind primary energy needs are estimated at approximately 14TW” . While conventional wind turbines fail to reach these altitudes, high altitude kites can achieve this altitude, efficiently and inexpensively. Makani, a different high altitude kite company, states on their website, “By using a strong flexible tether, energy kites can reach higher altitudes and eliminate 90 percent of the materials of conventional wind turbines, resulting in lower costs. Because they are more aerodynamic and can access stronger winds, each individual energy kite can produce 50 percent more energy” . There is an exorbitant amount of energy in the wind and we are barely able to scratch it with wind turbines. These high altitude kites would be able to harness more energy than a conventional wind turbine, while also doing so more efficiently and inexpensively. However, kite’s advantages over turbines are also evident in their availability. Turbines can only be installed in places with relatively high wind speed, usually between five to eight meters per second. Because of this, turbines are confined to a space of about fifteen percent of land around world . Kites, on the other hand, can be operated and can efficiently produce energy almost anywhere. In an article in Popular Science discussing high altitude kites to harness wind energy, Allister Furey, of the University of Sussex, states, “Pretty much anywhere in the UK you could run a kite plant economically, but you couldn’t run a wind turbine economically” . This is because kites, unlike turbines, are able to access high altitude wind, and this wind is available all over the globe. Because of this, new innovations in these high altitude kites have the potential to bring energy to places on the world where it is hardest to capture. The implementation of high altitude kites as a source of wind energy could prove a significant improvement in our attempt to find a clean and sustainable energy source.
Many of the companies currently developing high altitude kites follow the same general basic concepts, but vary on the specifics. I would like to focus on two companies in particular, Makani Power and KiteGen. Both of their kites generally work with the same method. These kites go through a cycle of three steps. The first step is the power generation process. During this phase, “The kite is flown dynamically in pattern-eight configuration, which induces high line forces. Meanwhile, the line is winched out, driving an electrical generator producing energy” . When the kite reaches a certain altitude, the transfer phase begins, in which the kite is brought to a neutral position . The final phase is the return phase. “In the return phase, the line is winched in, operating the generator as a motor while the kite is kept at a neutral wind window position… When the lower line length threshold is reached, the whole cycle repeats” . While energy is used during the return phase, it is much less compared to the energy that was generated during the power generation . While this is a standard process used with little variation between companies, their kites vary greatly. For example, Makani’s energy kite is a 27-foot-long structure with eight brushless DC motors and a carbon fiber and aluminum tether. . According to the company’s website, the kite, “simulates the tip of a wind turbine blade, the part of the turbine that makes most of the energy” . Furthermore, a computer system, “uses GPS and other sensors along with thousands of real-time calculations to guide the kite to the flight path with the strongest and steadiest winds for maximum energy generation” .
KiteGen, on the other hand, has a very different design for their kite. Their device resembles a large kite-like structure made out of aluminum. While both these companies use the same overall process to generate the energy, there are deviations in the more specific details. For example, Makani’s kites are flown in a circular path rather than the typical figure-eight path that KiteGen utilizes . While some of their methods may differ, their end games are the same. They are both attempting to provide wind energy in a more efficient and effective way.
While airborne wind energy is promising and has great potential for the future, it is still several years away from being an effective source of any energy. However, with the right investment for the future and innovation, kites have the potential to globalize wind energy. Right now, turbines are only effective in certain locations with high enough wind speeds. However, with the development of airborne wind energy, with energy could be used in places where it is currently not accessible . Furthermore, with enough development, kites could harness wind energy to power entire communities. Even today, with limited development, Makani’s aircraft can harness and generate enough power to power twenty homes . However, it may be several years until a company like Makani or KiteGen comes to market. These companies also face several challenges that must be overcome in order for airborne wind energy to grow. The Federal Aviation Administration will need to approve the companies’ methods, especially because electrified tethers at high altitudes can be dangerous . Furthermore, theses companies would have to convince regulators that their turbines will not collide will bird, not to mention other aircraft . Also, the research and test that these companies will have to run in order to develop a reliable prototype and product will cost thousands of dollars. Thus, companies will need to find funding for these projects. Makani has already found a solution to this problem, as they are currently being funded by GoogleX. Even when these companies finally develop their final product, it will still be a challenge to enter into the wind energy industry. “Even in the most optimistic scenarios, companies like Makani will need years to challenge the dominance of today’s wind farms. If the price of oil and gas stay low enough, airborne turbines may never succeed” . Despite the many challenges, I believe airborne wind energy could be an efficient, clean, and inexpensive source of clean and renewable energy.
While wind turbines have provided an adequate source of wind energy for decades, the conventional wind turbine is plateauing. Wind turbines are large, heavy, expensive, and hard to maintain while their locations are limited. Research depicts the immense power contained in the wind but the large majority of it is out of reach of the conventional wind turbines because it is located at such high altitudes. Airborne wind energy provides a solution to all these problems. It is a cheaper way to generate power from the wind, at any location. Although the technology is limited at this point, it could have the potential to generate much more power than the typical turbine, and because it is effective everywhere, wind energy could go to places it never could have with the conventional turbine. I care about this topic because I care about our environment. I believe that climate change is a significant threat to humanity and it will not subside until we find a clean renewable energy source to replace fossil fuels. I believe that wind energy is often overlooked as an energy source despite its enormous power. If airborne wind energy develops enough over the next couple of years, I believe it could be part of the solution in solving the world’s energy problem.