[dropcap]S[/dropcap]ome believed that tidal energy generation was an unrealistic dream. Engineering a turbine to withstand the harsh marine environment and operate at the seafloor appeared to be a challenge the world was not ready to meet. But today science fiction is a reality in the North Sea.
An underwater turbine that is set to be used in Scotland’s first and only consented tidal power project has successfully completed an initial testing period in Orkney, and is providing electricity for homes and businesses on the island of Eday, one of Orkney’s northern isles.
The 1MW power generator was installed last December, in some of the worst weather conditions Scotland has experienced in more than a decade, and has since been undergoing a range of tests in the fast flowing tidal waters around Orkney. The initial testing period has been very positive with the device achieving full export power.
The test device in Orkney aims to fully prove that the technology can operate efficiently in Scotland’s fast flowing tides, that monitoring and maintenance operations can be honed and to help drive down costs in operations and installation. ScottishPower Renewables (SPR) plan to use this technology as part of the world’s first tidal turbine array in the Sound of Islay. The company’s plans to develop a 10MW tidal array in Islay received planning consent from the Scottish Government in March 2011.
Keith Anderson, CEO of ScottishPower Renewables said: “The concept of generating electricity from the natural movement of the tide is still relatively new – and test projects like this are vital to help us understand how we can fully realise the potential of this substantial energy source.
“The performance of the first HS1000 device has given us great confidence so far. Engineers were able install the device during atrocious weather conditions, and it has been operating to a very high standard ever since. We have already greatly developed our understanding of tidal power generation, and this gives us confidence ahead of implementing larger scale projects in Islay and the Pentland Firth.
“Scotland has the best tidal power resources in Europe, and that’s why we are seeing world leading technologies tested here. This device is already providing renewable electricity for Orkney, but the potential is there in our waters to make a significant contribution towards our overall energy needs and our carbon reduction targets.”
The HS1000 tidal turbine has been developed by ANDRITZ HYDRO Hammerfest, whose majority shareholder is Andritz Hydro, and also includes partners Iberdrola and Hammerfest Energi. The 1MW machine can power the annual electricity needs of 500 homes.
Amazing as this feat of engineering is, it’s not the first of its type. A prototype device of a similar design has been generating electricity in Norway for over 6 years. That device is based on a mixture of technology used in traditional onshore wind turbines, subsea oil & gas production and in hydro-power plants.
The turbine can be monitored from the European Marine Energy Centre (EMEC) base in Eday, but engineers can also operate and inspect the device from Glasgow using mobile connections and an on-board camera.
Stein Atle Andersen, Managing Director of ANDRITZ HYDRO Hammerfest said: “The 1MW pre-commercial device is an important step in our staged strategy for developing reliable and cost efficient tidal energy converting devices and power plants. The tests being carried out so far have confirmed the design basis for the technology and given comfort concerning the device’s capacity.”
“We are still early in the testing programme with endurance, availability and reliability being the most imminent factors for asserting a proper basis for developing commercial tidal energy power plants. However, we are already well into design engineering for the first power plant.”
“In total we believe this is an important step forward for the industry in general by demonstrating that commercial size developments are feasible.”