In addition to world-class natural energy resources, Orkney also boasts some of the UK’s most innovative approaches to grid network management and energy storage. Proving the old adage that necessity is the mother of invention, the failure of Orkney’s electric grid to meet the needs of local renewable energy generators has turned the islands into a living laboratory for dealing with a green energy surplus.
Active network management
Due to the high cost of conventional grid reinforcement, network operator Scottish and Southern Energy Power Distribution (SSEPD) teamed up with the University of Strathclyde to design another solution to Orkney’s grid capacity constraints. Work on the ‘smart grid’ idea began in 2004 and an innovative new Active Network Management (ANM) approach was developed to make better use of the existing network by controlling generator output, in real time, to match the available network capacity.
In 2009, the fully operation ANM was switched on. It allows monitoring of the power flows at several points on the network, which results in the power flows from renewable generators to be controlled. The technology is based around a central controller, which collects data from ‘pinch points’ which are distributed around the network.
The ANM system allowed the connection of an additional 20 wind power generators with a combined maximum output of 24.2 MW. The Orkney Isles now have over 72 MW of distributed generation connected in addition to a further 5 MW of microgeneration. With over 77 MW of grid connected generation, the Orkney Isles became a net exporter of electricity in 2013 with 103% of demand met by renewable generation. Of this, over 40% was managed by the ANM system, delivering over £4m of benefit to the local economy.
After its success on Orkney, this pioneering ANM system is now being replicated in other grid constrained areas, including Shetland, the Western Isles and the Isle of Wight.
In 2013, Scottish Hydro Electric Power Distribution (SHEPD) installed a 2MW lithium ion battery at Kirkwall Power Station, and connected it to Orkney’s electricity distribution network. This pioneering trial, the first of its kind in the UK, aims to establish the viability of large scale batteries for electricity storage.
The 2MW lithium ion battery was provided by Mitsubishi, and has been integrated into the existing energy storage system within Orkney’s Active Network Management network. The battery, which has already been trialled for two years in Japan, should make it easier to smooth out intermittent power generation from renewable sources by allowing the operator to store clean energy and release it when required. This ability to balance a variable energy output from renewable sources will become increasingly important as the world moves towards a decarbonised electricity generation mix.
Although the installation of the battery has not provided an immediate solution to constraints on the Orkney distribution network, it is hoped that the results of the study will help demonstrate that batteries could provide a cost effective way of freeing up capacity on the network and facilitating new connections in the long term.
With a fleet of over 50 electric cars to be seen zooming around Orkney, we have one of the highest concentrations of EV’s in the UK. These range from personal cars to commercial vans, and Orkney Islands Council recently took delivery of the county’s first electric bus, which runs on the Kirkwall to Kirkwall airport route. The use of EVs in the county takes Orkney a step closer a carbon free lifestyle, and also helps to increase the local demand for renewably produced electricity, allowing Orkney’s renewables devices to generate that bit more to the grid. Some EV owners are even using their vehicles to circumvent the moratorium on grid connections, and are charging their vehicles directly from non-grid connected wind turbines.
Despite being some of the most productive machines of their kind and providing impressive returns in the early years, most Orkney’s community turbines have suffered heavy curtailment due their non-firm grid connections and the ongoing grid constraints faced by the whole county. In order to get around curtailment, Community Power Orkney are working together with bodies like Community Energy Scotland, Scottish and Southern Energy Power Distribution, and the local Council to investigate various innovative schemes to enable community turbines to generate more power, and therefore more revenue, for Orkney’s communities.
Surf ‘n’ Turf
In March 2015 the Scottish Government’s Local Energy Challenge Fund awarded £1.35 million to the Orkney Surf ‘n’ Turf project. The project is a partnership between Orkney Islands Council, the European Marine Energy Centre (EMEC), Community Energy Scotland and Eday Renewable Energy, and will use power from tidal and wind turbines to produce compressed hydrogen on Eday. This will then be transported to Kirkwall, where a specially designed fuel cell will convert the hydrogen to electrical power for buildings and berthed ferries at the harbour. This will not only reduce harbour costs, but will also bring new employment opportunities to local communities, as well as an additional source of revenue to be invested in local projects.
See also: The Orkney Energy Audit