Scotrenewables SR2000 being deployed at EMEC tidal test site (Credit Scotrenewables)

Orbital

Orbital Marine Power Ltd (formerly Scotrenewables) is an innovative Scottish engineering company focused on the development of tidal energy turbine technology with the potential to produce a step-change reduction in the cost of energy from tidal currents. The company currently employs over 20 staff with offices in Orkney and Edinburgh.

Orbital’s technology is a unique floating tidal turbine designed to provide a low cost solution for simplified and safe manufacture, installation, access and maintenance along with the ability to use low cost, small workboats for all offshore operations. The device hosts two propellers which fold up while being towed.

The technology has been under continuous engineering development, including rigorous testing of scaled systems in both tank conditions and open ocean environments since the company was founded in Orkney in 2002.

www.orbitalmarine.com

SR250

In 2012 the company achieved a world first when it exported power to the UK grid from its 250kW floating scale model, the SR250, at EMEC’s grid-connected tidal test site at the Fall of Warness. The 250kW device, measuring 33m long, was constructed at Harland & Wolff in Belfast in 2010 and weighs 100 tonnes. Initial tests involved short-term deployments of the device on its moorings followed by disconnection and towing back to harbour for inspection. The testing programme was undertaken in incremental stages, culminating in a three-month period of continuous grid-connected operation at the end of 2012.

SR2000

Building on the success of SR250, Orbital developed the SR2000, a larger 63 m, 500 tonne, 2 MW ‘commercial scale’ turbine more suited for tidal array deployment.

The SR2000 arrived in Orkney in June 2016, and was first deployed at EMEC’s tidal test site in October 2016. The SR2000 project was supported by Scottish Enterprise’s WATERS II scheme along with investments from Scotrenewables’ shareholders which include ABB, DP Energy, Fred Olsen, Total and Scottish Government via the Renewable Energy Investment Fund (REIF). The testing programme at EMEC was also supported via the FORESEA Interreg-NWE funded project.

At a rated capacity of 2 MW the SR2000 was the world’s most powerful tidal turbine. In early commissioning it reached a peak of 2.24MW export power at the EMEC substation.

During its test programme the SR2000 achieved the following milestones:

In 12 months of continuous generation into the Orkney grid the prototype turbine exported over 3 GWh of renewable electricity.
The entire project lifecycle of the SR2000 through construction, installation, operation and decommissioning was completed with small workboats or lighter. No heavy lift or large anchor handling vessels were used.
At times SR2000 was measured to have been meeting around 25% of total electricity demand of the Orkney Islands.
During the period of a measured full week of generation the SR2000 provided almost 8% of total electricity demand of the Orkney Islands.
At times output from the turbine was being used by EMEC to generate hydrogen for use in displacing fossil fuel-based usage on the Orkney Islands.
The SR2000 maintained rated power in seas of 2 m significant wave height and maintained generation is seas of 3. 5m significant wave height. The largest wave the turbine withstood was >6 m. The SR2000 saw instantaneous power generations of over 100 kW from wave power alone.
The quickest maintenance intervention time demonstrated by the Orbital operational team was under 40 minutes from quayside to turbine.

The SR1-2000 was removed from site in September 2018 to make way for the build and installation of their optimised 2MW floating tidal turbine, the Orbital O2, due to be installed at EMEC in 2021.

O2

The Orbital O2 2 MW turbine will comprise a 72m-long floating superstructure, supporting two 1 MW turbines on either side. The rotors span 600 sqm, the largest ever on a tidal generator.

75% of the supply chain for the O2 device is based in the UK.

The O2 has been built at Texo in Dundee and was recently moved to quayside at Prince Edward Wharf (see video). The device is due to be launched into the water in April 2021 and then towed to Orkney where it will be deployed at EMEC in summer 2021.

Horizon 2020 FloTEC project

The O2 will include an optimised superstructure design, 50% greater energy capture through increased rotor swept area, lower cost fabrication and maintenance strategies, compatibility with the local supply chain and infrastructure and mooring load dampers.

Leveraging £7m Horizon 2020 funding, Orbital are leading an industrial consortium comprising of the most experienced and committed commercial, industrial and research organisations involved in tidal energy today: DP Energy; Harland and Wolff Heavy Industries; the European Marine Energy Centre (EMEC); ABB Ltd; EireComposites; Technology from Ideas; University College Cork; EDF Energy and SKF, to optimise the SR2000 under the FloTEC (Floating Tidal Energy Commercialisation) project which is scheduled to be launched next year and deployed in the early part of 2020 at EMEC’s Fall of Warness tidal test site.

EMEC’s role involves undertaking an independent performance assessment which will provide evidence of the enhancements that have been made to the SR2000, de-risking the technology and improving investor confidence and supporting the technology towards commercialisation. Additionally, EMEC will carry out a comprehensive assessment of the environmental impacts associated with the deployment, which will feed into a broader assessment, considering wider impact issues such as fisheries, coastal and sedimentary geology processes, cultural heritage, socioeconomics and aesthetic impact.

www.flotectidal.eu

Interreg North-West Europe ITEG project

The construction of the moorings and actuation system of Orbital’s second generation tidal turbine, Orbital 2MW, is funded by the Interreg North-West Europe programme via the ITEG (Integrating Tidal Energy into the European Grid) project. Using excess energy generated by the Orbital 2MW turbine, this project will demonstrate an integrated hydrogen production solution in remote areas where grid export limitations exist. The project is scheduled to run until late 2020 and aims to bring down the pre-commercial cost of ocean energy by testing in a real environment and open up new market opportunities for the ocean energy sector via hydrogen production and energy storage. The ITEG project is led by the European Marine Energy Centre (EMEC) and includes the following partners in the consortium: Orbital, AREVA H2Gen, Energy Systems Catapult, Ghent Univeristy, Université le Havre Normandie, Université de Caen Normandie, Energy Valley and Agence de Développement pour la Normandie.

www.nweurope.eu/ITEG