By the most direct route, Slovaks need to travel over 360 kilometres to the nearest sea. In spite of this fact, Miroslav Kvaššay, who has been studying Mechatronics at the Brno University of Technology for five years, is developing an alternative source of energy to be used in sea buoys. And this April, he went to the sea after all to test the results of his diploma thesis directly in Barcelona, at the Faculty of Maritime Engineering.

How does a boy from Slovakia get to the sea buoys? It started quite inconspicuously. "Four years ago, Associate Professor Hadaš, who supervised my bachelor's and now also my master's thesis, sent us an e-mail with an offer to collaborate on the development of an alternative energy source for colleagues from Barcelona," recalls Miroslav Kvaššay, who agreed to the offer and immediately received the topic of his bachelor's thesis.

"We are working on the development of a generator that uses energy harvesting to power sensors for autonomous buoys at sea. These buoys are used, for example, for monitoring and marine research, they are designed to measure various data, such as temperature, sea salinity, water oxygenation and so on," says Kvaššay. But there is a catch – after a while, the batteries need to be replaced so that the sensors continue to work and the buoy can send data to the shore.

Energy harvesting, a process in which energy that would otherwise "lie fallow" is extracted from the waves of the sea and converted into usable electrical energy, can help with this. In the case of free buoys, it is the movement of sea waves, which Miroslav Kvaššay tries to convert into electricity so that the electronics in the buoy can be autonomous and the buoys do not require maintenance.

"I came up with a design incorporating two gearwheels – an internal toothing in which a smaller spur gear moves. By tuning their diameters, I am able to set the system's own frequency and thus achieve an optimum where the device works in resonance with the movement of the sea waves. Now I can say that I managed to create a generator with sufficient output power," Kvaššay happily explains.

His words are backed up by testing directly at sea. In April this year, he and his partner went on a trip to Barcelona, but he also combined his vacation with a visit to the local polytechnic university, with which he is developing the device. "My colleague there, Matias Carandell Widmer, managed to arrange a boat that was lent to us by his home Facultat de Nàutica de Barcelona, and we were able to test the device at sea in his WAVY buoy," adds Kvaššay.

"One day we prepared the buoy and tested it in the laboratory, the next day we were at sea for several hours and made two measurements there. The results were great. Mathias was able to use electronics that allowed data to be transferred from the buoy via wi-fi, so we could measure, capture and record data in real-time," Kvaššay praises the results.

The device has not yet been finalized, it will be necessary, among other things, to fine-tune the electronics that can effectively process the generator's output. Although Miroslav Kvaššay will soon finish his studies at the Faculty of Mechanical Engineering (no doubt successfully), he would like to continue his development. "Lately, I've been thinking that I would like to continue researching alternative energy sources. On the one hand, it is useful, and also very interesting. Unfortunately, there are not many companies that are engaged in energy harvesting yet, but they are gradually being established. And who knows, maybe I'll start my own in the future, we'll see," adds Kvaššay.

Miroslav Kvaššay is to return to Barcelona anyway. During the preparation of this article, he learned that he and his schoolmate Jakub Moravec, who works on a similar topic using his own approach, received a grant from EMSO (The European Multidisciplinary Seafloor and Water Column Observatory). "After defending our diploma theses, Jakub and I will go to Barcelona once again to perform measurements to verify the final version of our diploma theses," says Kvaššay happily.