From the Bristol Channel to the Outer Hebrides: The politics, economics, social consequences and environmental effects of harnessing the power of the seas in the 21st Century
A report from the 6th Bristol Tidal Forum and the 2nd Environmental Impacts of Marine Renewables (EIMR) Conference in Stornoway, Isle of Lewis, Scotland.
By: Alexander Portch
The sun is shining, the grass is green, blossom adorns the cherry and the hawthorn, and the mornings are filled with a cacophony of birdsong: the conference season has clearly arrived. Whilst the much anticipated 2nd World Congress of Environmental History in Guimaraes, Portugal, is still several weeks away, the interdisciplinary nature of my research into tidal power in the Severn Estuary is such that it seemed appropriate to attend the 6th session of the Bristol Tidal Forum on 24 April at the University of Bristol, before packing my bags and embarking on a more extended expedition to the farthest reaches of the British Isles to join the 2nd Environmental Impact of Marine Renewables (EIMR) Conference in Stornoway.
Whilst my research mainly adopts an historical perspective to study the various ways in which people have harnessed the power of the tidal cycle in the past, it is also my intention to consider how that practice may continue into the future, particularly if a barrage is never constructed. With the UK still faced with the need to massively reduce its reliance on fossil fuels by the end of the decade, thereby meeting targets imposed by the EU, and the likelihood that without further investment in new facilities for electricity generation the population, even in developed areas, could suffer from energy shortages, interest in the potential offered by wave and tidal power remains high.
This is particularly so in some of the more remote parts of the British Isles, where strong tidal currents and energetic wave environments are commonplace, such as the Orkney Islands and the Outer Hebrides. In the latter’s case, the scattered villages and isolated crofts are subject to the highest levels of fuel poverty in the UK and, being so far removed from the coal-fired power stations and nuclear power plants that provide the greater part of the mainland’s power, are in a precarious position with regards to their present and future electricity supply. In more recent times, small arrays of wind turbines have been built across much of Lewis; but wind is widely known for its fickle and unreliable nature, even in one of the most windswept places in Europe. It is in response, therefore, to the increasing demand for alternative sources of renewable and reliable energy in places like the northern and western isles of Scotland, and their possession of an unparalleled wave and tidal resource, that an embryonic industry has sprung up in the region and is rapidly increasing in scale and sophistication. In the southwest, too, the combination of a high tidal range in the Severn estuary, powerful tidal currents around the north Devon coast and Cornish peninsula and the high energy waves rolling in from the Atlantic, in addition to the strong winds that drive them, has been recognised through the creation of the South West Marine Energy Park. This is an initiative which seeks to foster collaboration and engagement amongst a variety of companies and organisations, including consultancies, think-tanks and tidal turbine developers.
All such developments have implications for the future of the Severn estuary. Will a barrage be constructed after all? Or will the estuary be divided up into a series of tidal lagoons, as may already be taking place with the recent plans for a lagoon in Swansea Bay? Alternatively, will the estuary be left unmodified to facilitate the widespread exploitation of the waves, winds and tidal currents further out to sea in the Bristol Channel? These are all options to be considered, particularly as each has significant implications for both humans and the non-human environment. With these thoughts and questions in mind, I took my first tentative steps into this year’s conference season.
The Bristol Tidal Forum is a relatively small-scale affair. Taking place over the course of a single day, the event was composed of a linear sequence of talks given by key individuals involved in the south west’s burgeoning tidal energy industry. As quickly became clear, these were mostly people working in the development and financing aspects of the sector, including the directors of engineering firms responsible for designing and building the devices themselves, representatives of organisations tasked with providing the financial support necessary to make such technology economically viable, and policymakers whose remit it is to ensure that the industry continues to develop in line with relevant guidance and government priorities. The environmental aspects of the technology were thus rarely touched upon, whilst the barrage was evidently far from most people’s minds. In fact, one speaker even went as far as to express frustration with the obstacles that have arisen in response to the deployment by their company of turbines in Puget Sound, in the Pacific Northwest of the USA, resulting from the need to monitor the resident orca (killer whale) populations. In many respects, the tone was set from the very beginning by Andrew Garrad of DNV-GL. In his opening address he laid the blame for any delays and difficulties in developing the industry on a combination of political and economic factors, rather than environmental concerns. Perhaps there is some truth in this assertion, and it is something I will be testing through my own historical study of the Severn barrage.
In marked contrast to the Bristol Tidal Forum, the EIMR 2014 conference, as the title implies, was very much focussed on the real and predicted impacts that tidal and wave energy generation may exert on “the environment”. With delegates arriving from as far afield as Oregon, Washington state, France and Spain, and bringing with them expertise in disciplines as diverse as social science, underwater noise propagation, monitoring of marine mammals and diving seabirds, maritime archaeology – and, in my case, environmental history – the resulting presentations, posters and coffee-break discussions proved to be enjoyably eclectic and adopted an open-minded perception of “the environment” as encapsulating human and non-human elements, as well as sentient and inanimate agents. Of particular interest were talks on community engagement as part of the development of tidal power in Nova Scotia, an area now favoured for tidal stream turbines, but also recognised for possessing one of the few operational tidal barrages in the world; a monitoring project centred on salmon around the coasts of Scotland which employed a combination of contemporary and historical tagging data, including some dating back to the mid-19th century; an overview by representatives of Historic Scotland of recently published historic environment guidance for wave and tidal energy developers[i]; and a poster which sought to demonstrate that construction of barrages around the UK, including one in the Bristol Channel, would significantly alter the tidal range as far afield as the Bay of Fundy and the coast of Maine.
What was perhaps most apparent, however, was just how substantial the impact of these new wave and tidal energy devices is likely to be for the marine and coastal environments; for both people and the rest of nature. Despite their relatively modest size in comparison to more substantial structures such as tidal barrages and lagoons, they may still pose a threat to marine mammals such as seals, basking sharks and whales, and seabirds, in addition to modifying tidal range and tidal current velocity, whilst also affecting rates of sedimentation and wave propagation. They could also pose a hazard for shipping, influence the size and frequency of waves currently enjoyed by surfers and other water users (although a talk on this subject with regards to the north Cornish coast suggested that the modifications imposed by the new WaveHub testing site near St Ives are unlikely to be particularly noticeable), and function as an eyesore for tourists and local inhabitants of coastal areas. What is also clear, however, is just how much people care about such issues and how enthusiastic they are about finding ways through which to overcome any problems inherent in the technology in order to facilitate the successful deployment of what could prove to be one of the “cleanest” and most “sustainable” forms of electric energy generation.
The excitement that currently surrounds the wave and tidal energy industry was perhaps most clearly demonstrated towards the end of my travels in the Outer Hebrides during a journey around western Lewis organised as part of the conference. In addition to visits to the Callanish Stones (Calanais in gaelic) – the Stonehenge of the north, according to some – the Gearrannan Blackhouse Museum and the Dun Carloway (or Dùn Chàrlabhaigh) Broch (thus satisfying my passion for all things archaeological and ancient), the trip took in the proposed site for the Siadar wave energy testing facility located on the north-west coast of Lewis. Developed by Aquamarine Power and employing their Oyster wave energy machines, this is set to become the largest single array of wave energy devices in the world, providing approx. 40 MW of energy to communities on the island. Whilst the devices will be mostly submerged beneath the water, they will nonetheless become visible at the surface during operation. Concern also surrounded the potential risks they pose for marine mammals, the important seabird population of Lewis, the area’s archaeological and historic environment resource, and any vessels that may pass nearby. Additionally, the visual aesthetics of the region were in danger of being compromised by the large number of metal objects scattered across an extensive swathe of coastline.
In contrast to many energy generation proposals, however, the Siadar site seems to be remarkable for overcoming all such potential obstacles. Seabird and mammal surveys have indicated that the area is largely devoid of any significant populations, and certainly isn’t used as a breeding ground or for feeding; archaeological remains are few and far between; shipping tends to be located further out at sea, away from such an exposed and rocky coast; whilst the decision to paint the devices in battleship grey with only a small amount of luminous yellow facing out to sea will keep their visual impact to a minimum. Local people are largely in support of the project, which will also make use of nearby insular harbour facilities and fabrication centres, and will benefit directly from the electricity produced at the site.
Indeed, as I flew back to Bristol from Inverness at the end of what had been a most enlightening and enjoyable venture, and gazed down upon the miles of offshore wind turbines sprouting contentiously from the seabed off the Lancashire coast, I couldn’t help but wish that all energy developments could be so straightforward and acceptable. On the other hand, if that were so, my doctoral research would be much less interesting! In reality even the Siadar wave site is a long way from completion, and it will undoubtedly encounter further challenges along the way. But the lessons learned from that development could prove instrumental for subsequent projects elsewhere in Britain, and further afield; including, perhaps, the Bristol Channel and the Severn Estuary. Thus, as I delve deeper into the libraries and archives, I will be sure to keep at least one finger on the pulse of the wave and tidal power industries of the 21st century.
[i]Firth, A. Historic Environment Guidance for Wave and Tidal Energy. English Heritage, 2013.