This MSc thesis was a project performed in a start-up that develops sustainable devices to exploit renewable energies, specifically in the field of energy harvesting in small scale. The objective of the thesis is to demonstrate the importance of developing the technical side of a project together with the development of the market. The idea is to enhance the success possibilities and work to get to the market as fast as possible with a minimum sellable product using the resources as efficiently as possible. The market analysis was the first step to be performed to understand what the start-up was getting into, at the beginning it was clear that the generator should be targeted to power remote applications that require small amounts of energy and a market that is not suitable for present technologies such as solar PV or micro wind turbines. After this a series of potential markets were identified in order to limit the research and three opportunities were selected. The buoy market was chosen, it has several sub-markets and the AtoN buoys, Fishing buoys and Meteorological buoys were considered the most important and suitable ones. Once the market was defined, the needs of the clients and users were discovered through research in the form of interviews and bibliographical research. Later on an experimental rig was used to test several models of the prototype under different parameters to select one that was close to what was demanded and that can actually be built. This approach was useful to dedicate resources efficiently, specially time and money. The last part of the thesis was to propose a sustainable business model describing a go-to-market strategy that considered both the limitations of the technology and the testing performed in the scope of this project and the expectations of the market for the proposed product. The methodology was a mixed use of business tools learned in the courses and the experiences of the people who were close to the start-up. There is a final reflection at the conclusions that describe the day-to-day of the start-up and the experiences learned as well as the recommendations for future work.