【特集】〝新〟風力発電：実証実験開始から約1年－課題解決に新たな一手【新潟】スーパーJにいがた9月23日OA

Located on the rooftop of the Teradomari Aquarium in Nagaoka City is a wind turbine with cylindrical blades. ■Pantaray, CEO Yasunori Sato "This wind turbine rotates using the power of vortices generated within a black cylindrical section and a ring behind it. The vortexes form a three-dimensional motion, wrapping around the ring." By placing a ring behind the cylinder, vortices are generated as wind passes through. These vortices then serve as propulsion, driving the cylindrical blades. Cylindrical blades have a simple shape, are easy to manufacture, and can be made from lightweight materials. Compared to conventional wind turbines, they rotate more slowly, reducing noise and improving safety. They are attracting attention for their potential to generate power in locations where installation was previously impossible. The company behind this development is Pantaray, an intra-university venture founded at Nagaoka University of Technology in 2021 and headed by Visiting Associate Professor Yasunori Sato. This wind turbine, which uses a rotating cylinder and ring mechanism, has been patented in five countries, including Japan. A demonstration experiment to verify its practicality will begin in September 2024. A prototype was installed on the roof. In June, nine months after the experiment began, Comparing the actual installation, we discovered something that wasn't there when the prototype was installed: ■Pantarei CEO Yasunori Sato "It's a wind collector that redirects the wind. The turbine itself doesn't swing, but faces in one direction. Instead, it has slits that allow wind coming from the side to hit the turbine." The results of the demonstration experiment, which aimed for even greater effectiveness: ■Pantarei CEO Yasunori Sato "Teradomari experiences winds of nearly 30 m/s. Strong winds in winter. It's a great achievement that we've been able to operate for nearly a year without any accidents or breakdowns." He emphasized the fact that the system "continued to operate." Sato felt confident that the system's ability to withstand strong winter winds, in its first outdoor demonstration, proved its high level of safety. On the other hand, ■Pantarei CEO Yasunori Sato "We know that we haven't achieved the power generation we originally anticipated." The problem identified was "power generation." It was about one-tenth of the target. The reason cited was the power generation mechanism. In the prototype, the generator rotated once for each rotation of the wind turbine, but this was not enough. ■Pantarei CEO Yasunori Sato "Our wind turbine itself rotates slowly, so the generator part needs to rotate at a certain speed to generate power." Furthermore, it was discovered that the wind turbine itself needed to be improved to generate more power. ■Pantarei CEO Yasunori Sato "We see this as a positive development, as it means we've identified what needs to be solved." On September 12th, approximately one year after the start of the demonstration experiment, A new prototype was completed in the university lab. ■Pantarei CEO Yasunori Sato "This windmill is made from balloon material. It's basically a balloon. Because it's inflated with air, it's very easy to make even large ones up to 2 meters in size. The larger the windmill, the greater the amount of electricity it generates." The material we chose to solve this problem was, of all things, balloons. By reducing the weight, we were able to create a larger windmill, 1.3 times larger than the prototype installed in Teradomari. It's also easier to assemble and transport. We found a research group developing vehicles made from balloons, and with their guidance, we developed the balloon windmill. ■Pantarei CEO Yasunori Sato "We were able to make balloon prototypes and asked a product supplier to make them for us. This was our first time making windmills and other shapes, so we went through several stages of prototyping." Furthermore, behind the windmill is— ■Pantarei CEO Yasunori Sato "In this prototype, we increased the windmill's rotation speed. Specifically, we increased the windmill's rotation speed by 10 times and transmitted it to the generator." For every rotation of the windmill, the step-up gear installed between it and the generator rotates 10 times. This ensures the required rotation speed for the generator and increases the amount of electricity generated per rotation. ■Pantarei CEO Yasunori Sato "We're finally getting close to the product stage. As with Teradomari, we'd like to send it out to collect data and identify areas for further improvement." In addition to research and development, we are also working to find companies with whom we can collaborate toward full-scale commercialization and mass production. ■Pantarei CEO Yasunori Sato "I feel that it would be difficult for Pantarei alone to commercialize a product. I think the key to a university-based venture is cultivating collaborators." Pantarei aims to commercialize various ...