In 2002, Orkney based wind developer and off-shore engineer, Barry Johnston, sought to apply his combined on and off-shore experience to develop the concept for a tidal turbine that in the long term would prove cost effective and robust in the harsh conditions of the tidal races of the world, such as the Pentland Firth. He identified from the outset that unlike onshore wind, the greatest challenge for tidal energy would be cost effective installation and maintenance of these turbines at sea. Around him, numerous designs were being developed which relied on installing and servicing the turbines with large expensive vessels from the nearby oil and gas industry. He quickly recognised that producing cost effective tidal energy using this approach would be very challenging.
Instead he embarked on developing a floating tidal turbine design which would be capable of being installed using only small, low-cost vessels, meaning the tidal energy sector would not have to compete for vessels with the oil and gas industry. The floating turbine could also be much more easily maintained as all the electrical generation equipment would be situated above the surface and easily accessed with a small vessel, unlike competing devices which must be raised from the sea-floor at considerable cost for maintenance. Another major consideration was that the tidal flow is much stronger closer to the surface and so a floating turbine could generate up to twice as much energy at the same location as a sea-bed mounted design.
Scotrenewables embarked on an extensive programme of proof-of-concept testing and received considerable support from the Scottish Government and Scottish Enterprise through the early years of development to progress the technology toward commercialisation. The company quickly grabbed the attention of major international players securing funding from TOTAL, the oil and gas major in 2006. This was followed by further investment by Fred Olsen Group in 2008 and ABB Technology Ventures in 2012. The company now has one of the strongest investment partnerships in the business.
Over the same period, the company has grown from strength to strength and has just completed a three year test programme of a 250 kW version of the device at EMEC. The turbine, which was part supported by Scottish Government WATES fund, has had an extremely successful testing programme, clocking up more than 4000 hours of operation, becoming the first floating turbine to export electricity to the UK national grid and becoming only the second marine energy device to undergo independent EMEC performance verification assessment. The turbine has been fully grid connected and exported electricity at rated power in a wide variety of wave and tidal conditions.
In 2014, building of the successful on the SR250 testing programme, the company announced the start of construction of its 2 MW commercial scale turbine, the SR2000, which once launched in early 2015 will be the most powerful tidal turbine in the world. Following a period of commercial demonstration, the turbine will be offered to the tidal industry with the lowest cost of energy production in the sector.