Annual Report 2017
Country Reports


Maria Olsson Swedish Energy Agency


Swedish companies, universities and institutes were involved with several research and development projects during 2017. Below are just a few examples.

R&D of dynamic low voltage cables between the buoy and floating hub in a marine energy system
Participants: Chalmers Department of Mechanics and Maritime Sciences, CorPower Ocean AB, Seaflex Energy Systems, Waves-4Power, NKT Cables AB, Minesto and RISE Research Institutes of Sweden AB
The project started in 2015 and will end during 2018. The objective of the project is to strengthen the ocean energy sector by establishing performance and design criteria to deliver a subsea electrical cable for dynamic environments. A mathematical model for power cables with fixings will be developed to simulate the cable movements and to calculate the fatigue failure of the electrical conductor. The model will be calibrated using different variants of prototype cables which will be produced by NKT Cables and tested in field trials for typically six months at the test facility at Runde Environmental Centre in Norway. Based on the model and field tests, a method for laboratory accelerated fatigue tests will be designed, set up and evaluated.

ELASTMOOR - Elastic mooring systems for wave energy converters
Participants: University of Lisbon, Chalmers Department of Mechanics and Maritime Sciences, Seaflex Energy Systems and Waves4Power
The project is an OCEANERA-NET research project, started in 2017 and will end during 2020. The project aims to improve the knowledge of using elastic mooring lines for wave energy applications. It will be achieved by collecting data from (i) laboratory testing of rubber, polyester and nylon lines, and of the coupled system of mooring and floater in an ocean basin test, and (ii) full scale field tests of Waves4Power’s wave energy converter. The results from the laboratory tests will be used for (iii) full scale field tests of a mooring in Portugal and (iv) the development of constitutive models which will be implemented in an in-house mooring dynamics numerical model. The simulation tool will be used to analyse the durability of mooring systems. Reliability analysis will be used to consider the statistical variability in parameters that have an influence on fatigue life.

Direct drive generator development
Participant: Royal Institute of Technology
The project is developing a new type of linear generator of transverse flux type that is predicted to be very efficient, low-cost and force dense. A prototype is being built in the lab of the Royal Institute of Technology which is aimed to demonstrate the technology. The prototype is to be demonstrated during the Spring of 2018.

Powerkite - Power Take-off System for a Subsea Tidal Kite
Participants: Midroc, ENGIE Lab Laborelec, Minesto, Chalmers University of Technology, Queen’s University Belfast, SSPA Sweden AB, AC&E, UW-ELAST AB and MoorLink Solutions AB
The project that has received funding from the European Commission started late 2015. It aims to develop a next-generation technology of tidal and ocean current power plant. During 2017, SSPA worked with the development of a more efficient turbine.

System design and development of wave power systems with centralized conversion to electricity (in a hub), and combining buoy and power take-off technologies
Participants: Ocean Harvesting Technologies AB, CorPower Ocean AB and Waves4Power
The project was funded by the Swedish Energy Agency and private investors and was completed during 2017. The objective of the project was to investigate whether hydraulic collection of power from wave energy converters to a central collection tower with gravitational energy storage and conversion to electricity can provide lower electricity production cost than more common de-centralized systems where electricity is generated directly in the buoy. The project demonstrated that in some cases the annual power capture could be increased by 10% with a hydraulic PTO. Nevertheless, the final electric output was reduced by 5% with the hydraulic system due to higher losses. Different storage capacities in the central gravitational energy storage were also investigated.

SSPA and Uppsala University are partners in the project MaRINET2 within the Horizon 2020 programme. The aim of the project is to facilitate research infrastructures for offshore renewable energy. SSPA has three major test facilities that are well suited for marine energy scale testing. Uppsala University operates the open sea wave test site Lysekil.

Testsite Skagerrak
“Testsite Skagerrak” aims to develop the opportunity for a common innovative environment that offers Swedish and international players both biological as well as technical offshore testing and demonstration sites. By combining and finding synergies in R&D activities in marine biomass, marine energy systems, underwater technology, etc., this development can be strengthened and coordinated into attractive offers. Customers are development companies, subcontractors, researchers and national and international R&D projects that can make use of the facilities. “Testsite Skagerrak” is in a planning phase to determine needs, focus areas and organizational set-up. The project is supported by the Swedish Governmental Agency for Innovation Systems (Vinnova), Västra Götaland region and Fyrbodal municipality.