ORKNEY'S ENERGY FUTURE
ABOUT ORKNEY
INTRODUCTION TO ORKNEY
The Orkney Islands – ‘Orkney’ – are an archipelago 16 km northeast of Scotland (Figure 1; [1]). There are 70 islands, 20 of which are inhabited, and a population of 22,270 [2] living in 10,155 households.
The temperate climate is influenced by the Gulf Stream resulting in Orkney experiencing a milder climate than other areas on the same latitude. The difference between average summer and winter temperatures is just 10°C: 15°C in summer and 5°C in winter [3]. Orkney is one of the windiest places in the United Kingdom, second only to the Shetland Islands (Figure 2; [4]), and strong gale force winds are common [5]. The islands are relatively low-lying with an average elevation above sea level of 27 m. The highest point is Ward Hill on Hoy at 481 m. Orkney is mostly treeless with just remnants of native woodland still intact [6].
Figure 1: Map of the Orkney Islands [1].
Orkney has a higher employment rate than the Scottish average (87% [7]). However, average weekly and hourly earnings are lower in Orkney, equating to around £1,040 less per annum [8]. Employment is most commonly provided in the human health and social care sector (18.2%). Professional, scientific and technical jobs account for 4.5% of jobs in Orkney compared to 7.2% across Scotland [8]. The main industries are agriculture, fishing and oil due to the Flotta oil terminal which processes crude oil from several North Sea fields. Over the last 20 years sectors such as tourism, food and drink, and more recently, renewable energy have grown [9].
The largest age group is 45 to 64 and this is expected to remain the case despite a projected 37.4% increase in the 75 and over age group between 2018 and 2028 [2]. This ageing population is typical of islands, where younger working age people can be drawn away to better career and employment prospects in larger communities [10].
Figure 2: UK mean wind speed annual average 1981-2010 [4].
THE ENERGY ISLANDS
The geographical situation of Orkney means that opportunities to generate electricity from renewable sources – wind, tide and wave in particular – are significant. The islanders are forward thinking in the renewable energy space; Orkney is the home of Scotland’s first community owned wind turbine and the number of electric vehicles per capita is greater than in Scotland [11]. The establishment of the European Marine Energy Centre (EMEC) Ltd in 2003, the world’s first facility to test wave and tidal energy converters, demonstrates the advantageous position of Orkney in being able to harness power from the surrounding waters [12]. At present there are no wave or tidal projects deployed at scale and as such the majority of renewable electricity generation is from onshore wind.
GOAL TO DECARBONISE
The Climate Change Act 2019 set out targets to reduce Scotland's emissions of greenhouse gases to net-zero by 2045 as well as an interim target for a reduction of at least 75% by 2030 compared to the baseline of 1990 [13]. In line with this, Orkney has set its own goal to fully decarbonise its energy system in 2030 and eliminate the need for fossil fuels. To achieve this is likely to be a significant challenge. Data from the 2019 Orkney energy audit [14] and UK Government [15] show that greater than 80% of the current energy demand is provided by fossil fuels. This has resulted in Orkney’s carbon emission intensity per capita being 64% greater than that of Scotland (Figure 3; [16]).
Figure 3: Orkney energy demand by fuel type and carbon intensity compared to Scotland and England [16].
ELECTRICITY NETWORK AND CURTAILMENT
Orkney is connected to the Great Britain electricity network via two 33 kV subsea cables, installed in 1982 and 1988, with a combined capacity of 40 MW. In the early 2000s, electricity was sourced via these cables as well as the Flotta gas turbine and Kirkwall diesel power station with a small amount of electricity coming from renewables (Figure 4). To manage the increase in onshore wind capacity that began in 2008 (Figure 5), an Active Network Management (ANM) system was introduced in 2009 which instructs generators to control their output in real time to match the available network capacity. However, by 2012 its limit had been reached and there was a moratorium on new connections because the electricity grid was operating at capacity. The increased onshore wind capacity led to Orkney generating a surplus of electricity and therefore becoming a net exporter in 2013. In 2020 additional capacity was released on the distribution network and the suspension on new generation connections was lifted allowing applications to made to the ANM system [17].
Figure 4: Timeline of Orkney’s energy history from 2000 to 2020.
Figure 5: Installed onshore wind capacity 2000 to 2020.
The success of onshore wind in Orkney has, however, led to problems. Due to the limitations of the inter-island electricity network and the 40 MW export limit to the mainland, it is not possible for all the surplus electricity to be exported. The constrained electricity network causes high levels of ‘curtailment’, where wind turbines are switched off to protect the network from overloading, controlled in part by the ANM. The curtailment means that turbines do not operate at maximum capacity, leading to frustration amongst infrastructure owners. Additionally, revenue that could have been realised through Feed-in Tariffs is lost.
On an annual basis, the curtailment can result in lost output of greater than 37%. Between 2014 and 2018, the electricity that was lost ranges from 104 to 118 GWh/year (Figure 6). In 2018 the 38% curtailment equated to lost Feed-in Tariff revenue of approximately £3.3 million, including ~£2 million from turbines that are community owned, enough to fund at least 140 11 kW air source heat pumps.
Figure 6: Generated electricity from onshore wind and lost output for 2014 to 2018. Lost output is due to curtailment of wind turbines.
Both 33 kV cables are required to be in operation to meet current peak electricity demand and if one is not operational demand has to be met primarily from Kirkwall diesel power station [18]. A technical and economic case has been put forward in support of a new 220 MW high voltage alternating current (HVAC) electricity transmission link between Orkney and mainland Scotland. This would allow current wind farms to operate at maximum capacity, support new connections, provide demand security and avoid the need for the diesel power station [18]. The transmission link was given conditional approval by Ofgem in 2019 with a connection date of April 2023, however it is likely that this will be delayed [19].
USING THE SURPLUS ELECTRICITY
Orkney has a surplus of electricity and aims to fully decarbonise by 2030, despite 85% of the energy demand being met by fossil fuels (non-renewable sources). This project proposes using the surplus electricity to decarbonise carbon intensive sectors of the economy, with focus on:
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Domestic buildings
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Road transport
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Marine transport
which account for 58% of the non-renewable energy consumption (Figure 7; [14] [15]).
Figure 7: Breakdown of Orkney’s non-renewable energy consumption in 2018.
REFERENCES
[1] Maps of Britain, "Map of the Orkney Islands," 2004. [Online]. Available: http://www.maps-of-britain.co.uk/map-of-orkney-islands.html. [Accessed 5 April 2021].
[2] National Records of Scotland, "Orkney Islands Council Area Profile," April 2020. [Online]. Available: https://www.nrscotland.gov.uk/files/statistics/council-area-data-sheets/orkney-islands-council-profile.html. [Accessed 9 February 2021].
[3] Orkneyjar, "The Climate of Orkney," 2021. [Online]. Available: http://www.orkneyjar.com/orkney/climate.htm. [Accessed 7 April 2021].
[4] Met Office, "Where are the windiest parts of the UK?," [Online]. Available: https://www.metoffice.gov.uk/weather/learn-about/weather/types-of-weather/wind/windiest-place-in-uk. [Accessed 5 April 2021].
[5] F. Arfin, "Weather in Orkney: Climate, Seasons, and Average Monthly Temperature," 12 May 2020. [Online]. Available: https://www.tripsavvy.com/whats-the-weather-like-on-orkney-1662475. [Accessed 7 April 2021].
[6] Orkney Communities, "Orkney Woodland Project," [Online]. Available: https://www.orkneycommunities.co.uk/woodland/index.asp?pageid=595130. [Accessed 7 April 2021].
[7] Scottish Government, "Scotland's Labour Market: People, Places, and Regions - Statistics from the Annual Population Survey 2019," 27 May 2020. [Online]. Available: https://www.gov.scot/publications/scotlands-labour-market-people-places-regions-statistics-annual-population-survey-2019/. [Accessed 8 February 2021].
[8] Nomis, "Labour Market Profile - Orkney Islands," 2019. [Online]. Available: https://www.nomisweb.co.uk/reports/lmp/la/1946157427/printable.aspx. [Accessed 8 February 2021].
[9] Orkney.com, "Economy," 2021. [Online]. Available: https://www.orkney.com/life/live/economy. [Accessed 26 April 2021].
[10] R. King, "Geography, Islands and Migration in an Era of Global Mobility," Island Studies Journal, vol. 4, no. 1, pp. 53-84, 2009.
[11] C. Silver, "Orkney: The 'Energy Islands' Penalised for Becoming Too Clean, Too Soon," 10 March 2019. [Online]. Available: https://www.desmog.co.uk/2019/03/10/Orkney-Energy-Islands-Penalised-Too-Clean-Too-Soon. [Accessed 9 February 2021].
[12] EMEC, "About us," 2021. [Online]. Available: http://www.emec.org.uk/about-us/. [Accessed 6 April 2021].
[13] Scottish Government, "Climate change," [Online]. Available: https://www.gov.scot/policies/climate-change/. [Accessed 7 April 2021].
[14] Orkney International Science Festival, "Orkney's Energy Revoution: Hydrogen & Energy Systems," YouTube, 3 September 2020. [Video File]. Available: https://www.youtube.com/watch?v=TCfYGdsSXSc&t=2389s. [Accessed 1 February 2021].
[15] UK Government, "Road transport energy consumption at regional and local authority level," 25 June 2020. [Online]. Available: https://www.gov.uk/government/statistical-data-sets/road-transport-energy-consumption-at-regional-and-local-authority-level. [Accessed February 2021].
[16] UK Government, "UK local authority and regional carbon dioxide emissions national statistics: 2005 to 2018," 25 June 2020. [Online]. Available: https://www.gov.uk/government/statistics/uk-local-authority-and-regional-carbon-dioxide-emissions-national-statistics-2005-to-2018. [Accessed 7 April 2021].
[17] Scottish and Southern Electricity Networks , "Orkney distribution network opens to new renewable generation connections," 18 September 2020. [Online]. Available: http://news.ssen.co.uk/news/all-articles/2020/september/orkney-distribution-network-opens-to-new-renewable-generation-connections/. [Accessed 2021].
[18] Scottish and Southern Electricity Networks , "A Whole System Opportunity - Realising Whole System Benefits for Orkney," [Online]. Available: https://www.ssen.co.uk/WorkArea/DownloadAsset.aspx?id=17161 . [Accessed 2021].
[19] Ofgem, "Decision: conditional approval of the SWW Final Needs Case for the Orkney electricity transmission project," 16 September 2019. [Online]. Available: https://www.ofgem.gov.uk/system/files/docs/2019/09/conditional_decision_on_orkney_final_needs_case_2.pdf. [Accessed 7 April 2021].
[20] UK Government, "Regional and local authority electricity consumption statistics," 22 December 2020. [Online]. Available: https://www.gov.uk/government/statistical-data-sets/regional-and-local-authority-electricity-consumption-statistics. [Accessed 18 February 2021].