In the last few decades, renewable energy technologies became popular due to the serious environmental situation of the planet. Wave energy converters (WECs) are the systems which convert the wave power into electrical energy and they are currently under research and development. The most popular WEC is the point absorber, a device which converts sea wave energy into electricity, and its movement is typically in the vertical direction. The current thesis presents an interconnected point absorber system which aims to increase the performance of the device using an innovative power extraction technique. In particular, horizontal tethers have been added in order to connect the point absorbers, and therefore to exploit their relative movement in surge direction.