SRTP Complete First Phase of Power Generation Tests - August 2011
Scotrenewables Tidal Power Limited have progressed the development of their prototype tidal turbine, the SR250, by completing the first series of power generation tow tests. This marks another successfully completed phase of their incremental research and development programme for the tidal turbine.
Principal Electrical Engineer Trevor Walls highlighted the importance of conducting power generation tests in a controlled manner before subjecting the device to on site tidal conditions stating that ‘in a prototype device such as this it is crucially important to bench test all the primary and auxiliary systems before the device is in its fully operational status. Towing the device gives us a much greater degree of freedom, allowing us to have complete control over the generating conditions and to tweak elements of the control system safely and as required in real-time'.
Scottish Energy Minister Visits Scotrenewables Tidal Power Ltd - 21 June 2011
The Scottish Energy Minister and Rural Affairs Committee paid a visit to Orkney this week. Ian Davidson MP, Chair of the Committee, said: "The majority of our meetings and visits will focus on aspects of the committee's inquiry into the Crown Estate in Scotland, particularly in examining how it can best act in the public interest and its relationship with local communities which are directly affected by the decisions it makes. In addition, we will also seek information as to how employment and enterprise are being sustained in the present economic difficulties."
Part of the visit included a meeting with the Scotrenewables management team and tour of the SR250 device at Hatston Pier. The minister expressed thanks for an informative meeting stating: “I was very impressed to see the progress that you have made and pleased to hear that the support provided through the Scottish Government WATES scheme has proved an important part of this development. The issues raised during our meeting have provided me with valuable insight into the key challenges facing marine renewable development”
Scotrenewables Tidal Turbine Generates Power - 26 July 2011
Testing of the SR250 tidal turbine took a major step forward last week as the device generated power for the first time. This marks a major milestone for the team at Scotrenewables Tidal Power Ltd who have been developing the floating turbine from their base in Stromness.
The floating tidal turbine has been visible at Hatston pier for several months while it has been undergoing commissioning since arriving in Orkney waters in April. The first power generation is the most significant milestone to be met since an initial grid connection of the turbine at the EMEC test site shortly after the device arrived in Orkney. Chief Technical Officer Mark Hamilton explained “we’re very happy to be reaching the end of the commissioning process and to be generating power. Successfully producing power from the turbine means that the many different electrical, mechanical and hydraulic subsystems are all working well together. Progress has been steady since we got the machine home to Orkney and we are delighted to now be looking towards the next stage of testing in the Fall of Warness.” The 250kW machine is to undergo a 2 year test program at the EMEC test site near Eday.
The device generated power for the first time during tow trials with the MV Voe Viking in Shapinsay Sound. Equally as important as generating power for the first time, the tow trials have proved that the primary design criteria of building a tidal turbine that can be easily handled with a modest sized work boat has been met. The team plan to take full advantage of the ease of handling and connecting/disconnecting the device from its moorings by regularly bringing the device back and forth to Hatston pier for maintenance and inspection over the 2 year testing program.
Managing Director Barry Johnston said “at every stage of building and testing the SR250 we have learned invaluable lessons that will feed into the design of our commercial scale 2MW device. Producing power for the first time is of course a major step forward, but I am equally pleased with the lessons learned by the team while commissioning the turbine in Hatston and the experience we are building up of handling the device at sea.”
Floating Tidal Turbine Arrives in Orkney - 11 March 2011
This week sees the arrival in Orkney of a full scale prototype floating tidal turbine, the SR250, which has been designed and developed by Stromness-based Scotrenewables Tidal Power Ltd. The arrival of the device marks the successful completion of the latest phase in the development and commercialisation of the company’s innovative tidal turbine concept. The philosophy behind the design is ease of installation, access and maintenance. All installation and operational activities can be undertaken using a standard multi-cat work vessel which has the advantage of being readily available and relatively cheap compared to offshore anchor handlers or jackup barges. The company previously has received financial backing from the Carbon Trust, the Scottish Government and more recently has attracted substantial private inward investment from Fred. Olsen Renewables and energy company TOTAL. Ultimately the goal is to focus on undertaking commercial deployments in sheltered tidal sites and ‘run-of-river’ projects worldwide.
The results of 1/5th scale device testing, which concluded in August 2010, informed the final design of the 250kW device, which has been constructed and commissioned by Scotrenewables staff over the past 6 months at Harland and Wolff in Belfast. The build has been completed in record time and within budget. While many of the team were occupied in Belfast, a small number of engineers remained in Orkney at the beginning of the year to install the mooring system and a new subsea cable at a specially selected site at the European Marine Energy Centre (EMEC) testing facility near Eday. Taking advantage of relatively calm weather for the time of year, the mooring system was installed in 16 hours, and the 3km of subsea cable laid in approximately 20 hours.
While the operations at the EMEC test site will be critical in the testing programme, due to the nature of prototype testing the device will undergo intermittent testing at the test site and will not remain onsite permanently. Chief Technical Officer Mark Hamilton explained “the SR250 is an intermediate scale device built to undergo a series of sea trials in and around Orkney waters over the next 2 years. We will gradually increase test durations onsite at EMEC as confidence is built in the performance and handling of the device. A major advantage of our floating technology is that can be easily towed to and from site for inspection and maintenance at harbour side. During the test programme we will be carrying out regular trips to and from our test site at Eday to our maintenance operations base at Hatston Pier in Kirkwall. We are aiming to collect a few months of data in different environmental conditions from this prototype to inform the design of a larger commercial version.”
Managing Director Barry Johnston was keen to stress the importance of approaching the project in carefully managed incremental stages stating that ‘we still have a lot to learn and having the ability to test the SR250 in open-sea conditions will provide the team with the crucial experience needed before progressing on to the full-scale prototype, 2MW commercial device. It is however very unlikely that the future deployments will be within the Pentland Firth as we plan to focus our efforts on more sheltered sites and run-of-river opportunities worldwide. The SR250 prototype is the result of a tremendous effort by our team of dedicated engineers who all deserve to be congratulated for their efforts particularly over the past six months.’
Scotrenewables award contract for manufacture of 250kw Tidal Turbine (SRTT) prototype.
Harland and Wolff Heavy Industries Limited have been awarded the contract to build the latest cutting edge prototype tidal turbine by Orkney based Scotrenewables.
The 30m long 250kw device is approximately a 1/4 scale power take off model of the full size device. The prototype will be manufactured in Belfast before being deployed at the European Marine Energy Centre (EMEC) test facility in the Orkneys.
Harland and Wolff Engineering Manager Fred Black said, ‘Harland and Wolff have been very active in the renewables market for many years now and Scotrenewables tidal turbine belongs to a small group of developers who have concentrated not just on the conversion technology, but importantly on making the device easy to install and maintain. Our input was to assist their engineers develop the design to make it production friendly. This makes it cheaper to manufacture and enhances quality.’
Scotrenewables’ Managing Director Barry Johnson said, ‘We’re delighted to continue working with Harland and Wolff on this important development. The Scotrenewables Tidal Turbine is a major step forward in marine renewables and this large scale model is a massive step toward proving the productivity, reliability and importantly the ease of operation and maintenance that is inherent in our design.’
He continued, ‘Each full-size SRTT will be circa 43.7m long with a draught to the rotor axis of 11m in operation mode. The rotors will be 12m diameter for the 1.0MW prototype device. The SRTT concept is designed for deployment in any water depths of >25m and mean spring tidal velocities of 2.5m/s to over 5m/s which covers 70% (Carbon Trust, 2006) of the UK tidal resource. In the transport mode the maximum depth of the SRTT is limited to 4.5m to allow access into most harbours for maintenance.’
Harland and Wolff Manufacturing Manager Trevor McCormick commented, ‘We’re delighted to be involved in this project. We have a strong track record in the marine renewables sector and understand the importance of this prototype and the trust that Scotrenewables are placing in us. We look forward to working with them and seeing the prototype prove itself.’
Some key benefits of the technical features include:
• Floating design – enables turbines to be in region of typically highest tidal velocity
• Compliant Mooring System - enabling deployment in deep waters
• Passive Yaw System – improve energy conversion, simplify design
• Fixed Pitch Rotor Blades – to reduce design complexity and cost
• High performance, low mass
• Rapid connection/disconnection
• Maintenance carried out inshore/in harbour
Figure 1 – SRTT Operation Mode
Figure 2 – SRTT Transport/Survivability Mode
Harland and Wolff Heavy Industries Limited
Tel +44(0)2890 534389
Tel: +44 (0)1856 851641