Global electricity demand doubled between 1990 and 2016 and several countries are planning for a significant increase in offshore renewable energies along the European coast. In 2015 renewable energy accounted for more than half of the new generating capacity installed in the power sector worldwide. These activities bring up an increased interest about possible environmental impacts or additional values of the new technologies. The Wave Energy Park "Sotenäs Project" is located on the west coast of Sweden, 120 km north of Gothenburg, and was the site for environmental impact studies from wave energy generators on two sea pen species, Virgularia mirabilis (Müller, 1776) and Pennatula phosphorea (Linnaeus, 1758). Sea pens and burrowing mega fauna communities are designated threatened or declining habitats or species by the OSPAR convention. Investigations of those taxa in relation to marine renewable energies are thereby both interesting and important. A ROV aided seabed survey in the wave power park and respective control areas were primarily conducted to assess Nephrops norvegicus (Linnaeus, 1758) abundance and video footages were used to compare the abundance of the two sea pen species within the same area. Preliminary results show a significant difference between the transects and years. However, a clear increased number of individuals inside the wave power park for the two sea pen species compared to the control transects were not identified. Long-term observations and complementary studies are necessary in order to draw firm conclusions.