Decision support for renewables
Forum: Marine Energy…
Decision support for renewables
Forum: Marine Energy
Scientists in Scotland are leading the way in researching the environmental impact of marine renewables – using Scotland's waters as a test-bed to study the long-term effects of the new generation of wind, wave and tidal technologies coming on-stream and helping to de-risk their future deployment...
Everyone would like to get energy out of the sea as cheaply as possible, causing as little damage as possible, but wave and tidal-stream technologies are in the early stages of development and we're only beginning to learn about their long-term impact on the natural environment. It may be relatively easy to calculate their physical impact on the ocean itself, but their complex effects on the physiology and behaviour of birds, fish and mammals are harder to predict – not just out of academic interest but also to address wider public concerns and avoid contravening international laws.
Environmental scientists in Scotland are ready to get down to business and keen to see more marine renewables being deployed. “Five years ago, we didn't have the tools required to measure their environmental impact,” says Dr Ben Wilson of SAMS (the Scottish Association for Marine Science). “Nothing ‘off the shelf’ worked, so we had to develop our own tools, and now we need to get more devices into the water – not just a few demonstration machines but working arrays.”
Getting data from the real world is a major challenge facing researchers, as the industry gathers momentum. According to Dr Ruairi Maciver of Lews Castle College, who models the “physical processes of the ocean,” there isn’t enough data in the regions of interest: “Ideally we’d have ten years of field measurements at a particular site to calibrate our models, but we have to rely on a handful of shorter periods, often at a different location. Developers need to protect their interests and are cautious about releasing data, so we have to work with what is in the public domain.”
Professor Paul Thompson of the University of the Aberdeen adds that “the world will never be as perfectly described as we would like it,” and that we already have significant data, despite the fact the industry is still embryonic. He also points out that the wave and tidal-stream industry is much less mature than the wind industry in terms of engineering viability and economics, as well as more diverse in terms of competing designs – and no-one has made any money yet from their investment. But scientists are making rapid progress in gathering data and piecing together the environmental jigsaw, in collaboration with developers and other bodies. A few years ago, says Thompson, it was difficult for scientists to persuade industry and regulators that it was in everyone’s interests to pool their resources, but “we are getting there,” he adds.
Scotland the test bed
These may be early days for wave and tidal power, and these schemes may never fulfil their potential, but the number of offshore wind turbines installed in the waters around the UK, and the wide range of new wave and tidal machines being tested in locations such as Scotland’s Pentland Firth, will increase significantly over the next few years. Predicting their effect on the environment, however, is complex. It may be possible to model the hydrodynamics (the waves and currents, etc.) and also map the whereabouts of mammal, bird and fish populations (including their migration cycles and habitats), but nothing beats a study in the real world. And according to Thompson, Scotland is well placed to take the initiative in such a project, and also have an international impact.
“Getting baseline data from lots of individual sites is not the answer,” says Thompson. “That is spreading ourselves much too thinly. We need to be more strategic and identify a few key demonstration sites (e.g. the Pentland Firth) where we can do much more in-depth research, pooling our resources to answer key questions about the longer-term ecological impact.” This research could be coordinated with parallel studies – for example, in the Pacific – to compare results and try to reach some general conclusions. We also need to ask specific questions as soon as the devices are put in the water, says Dr Beth Scott, a senior lecturer from the University of Aberdeen – for example, “is there a predictable pattern to where species are most active in the water column to predict accurate risks of collision?”
The growing international interest in Scotland’s marine renewables sector is reflected in the number of overseas delegates coming to the Environmental Interactions of Marine Renewable (EIMR) Energy Technology Conference in Stornoway from April 28 to May 2, 2014. “Scotland is the focus of the wave and tidal industry,” says Thompson, “and we’re also ahead in research into deep-water wind farms.”
Even though environmental scientists have personal opinions on the issues involved, their primary job is to ask the right questions and gather the evidence needed to inform the debate. As the EIMR conference states in its programme, “the main objective is to bring together people from different disciplines and cultures to encourage collaboration and development of ideas,” and the ultimate aim is to “yield positive outcomes for all” – i.e., not just the government and public but also the investors and developers, as well as the planet itself.
“We’re looking at the long-term cumulative impact of putting these devices in the sea,” says Hastie, “but what about the long-term impact of not putting them in?”
The human factor
The effects of human activities on marine mammal, seabird and fish populations have clearly increased through the years, but natural changes in environmental conditions also affect different species, and this has to be disentangled from man-made effects. Scientists are also concerned about the effects of renewables throughout the food chain, and understanding the underlying ecology, rather than focusing on isolated incidents.
As well as being careful when it comes to the science, researchers have to be aware of the complex politics involved in the energy business. An “army of consultants” are involved in environmental impact assessments, but there are still a lot of “unknown scientific issues,” says Wilson, and everyone is having to learn very quickly as the industry grows. “As soon as a device goes in the water,” he adds, “the lawyers show up.”
Marine scientists are keen to partner with developers, but most of the early investment goes to prove the technical and economic viability of devices, rather than gathering data on possible environmental impact. The environment is “left until the later stages of development,” says Maciver. “We know where to focus now,” Wilson adds, “but there are many economic constraints and the timetabling must be pragmatic so we can tool up to meet the challenge.”
Wind energy is at a different stage in the cycle, says Thompson. Companies in this sector have already proved the basic technology works and have some degree of economic certainty, so environmental impact assessment is essential to future success, to optimise investments and also get planning consent – especially for larger-scale wind farms located in deep-water sites. Wind is currently also “a much bigger pie,” Thompson adds, compared to much smaller scale tidal and wave.
The need for more data
Whether it is wind, wave or tidal renewables, everyone – including regulators – is hungry for data. However, according to Thompson and Scott, a lot of the baseline data collected by offshore developers cannot be used to ask broader scientific questions, and may be insufficient to undertake Environmental Impact Assessments. “Even though a lot of data has been collected, the variety of methods used and the lack of access to allow the raw data to be collated is hampering the ability for that data to be more useful,” says Scott. There is a lot of information on the distribution and abundance of species, adds Thompson, but on its own this does not allow regulators to assess how different species will respond to the deployment of renewables. “The challenge is to get more realistic information and develop the right research programmes,” adds Hastie.
Scott also says marine renewables present a different challenge to developers because “they think we scientists know it all already and they can't believe how much we don't know about the marine environment.” The “connectivity of data” is also important. You may know where birds are at any one time, but you don't necessarily know which colony and therefore which population they are from unless you tag a lot of birds – for example, tagged birds from Fair Isle have been found to be feeding off Fraserburgh.
It has been suggested that the renewables industry is evolving so quickly that a shortage of good data is inevitable, but Thompson also points out that renewables is the “first major marine industry that has had to face
this level of assessment.”
“We need baseline data that describe the present situation, but we need to pose the right questions for assessing impact and then define consistent methodologies for answering those questions – and this may require new tools,” says Maciver.
Maciver specialises in measuring and modelling “the physics of the sea,” and stresses the importance of conducting both pre-deployment measurement studies, to identify the best sites, and then post-deployment studies, to assess the impact of renewables. “We can model many of the processes that occur in our inshore coastal waters,” he says, “but it is not yet clear how to represent renewables in these tools.”
Good or bad vibrations?
The potential impact of renewables is complex and involves multiple factors. For example, noise can be disturbing to marine life and moving parts in turbines can sometimes be fatal, but another subject where research is needed is the impact of vibration on the sea bed, during operation as well as construction. What if sand eels (food for seabirds) are disturbed by vibrations from turbines, responding as if they are under attack and exhausting themselves in the process? And are these vibrations any worse than the effects of a storm?
In addition, not all human interventions are bad for marine life – some animals are attracted to oil rigs or wind farms and thrive there. “You sometimes get a benefit you did not anticipate,” says Scott – e.g., most renewables sites will also be de facto Marine Protected Areas because they will exclude the more physically disruptive fishing practices such as dredging. “We have to balance the environmental benefits and impacts,” says Thompson.
“Everybody has an opportunity to learn now,” he continues. “The data are not always perfect, but there are many ways that we can help the regulators and the industry develop the decision support tools they need. Twenty years from now, we don’t want to look back and wish we had done more research.”
The science may be relatively young in many ways, and all the big challenges still lie ahead, but scientists in Scotland can already claim several successes, apart from attracting international attention. For example, says Thompson, “Scotland is the first country to be able to consent deep-water offshore wind farms, confident they don’t infringe EU directives, thanks to a massive collaboration between industry, government and academia, plus the consultants, working together to scope out the issues.” The technology is proven and the industry is now ready to embark on large-scale commercial projects.
Wave and tidal energy developers still have to prove the technology works. But a new scheme in the Pentland Firth should help to accelerate progress, with six tidal turbines providing the opportunity to monitor environmental impact close up, by lowering a platform packed with instruments into the sea.
If the Pentland Firth and other marine sites in Scotland can also fulfil their potential, collaboration will be critical, with scientists, investors and developers, utility providers, government and regulators working in tune with the public to enable new technologies to come on-stream with minimal environmental impact.
For that to happen, government organisations such as Marine Scotland will also play a key role by funding research. “No-one can do this in isolation,” says Hastie, “and one advantage we have in Scotland is that everyone knows each other.”
Scientists now have a clear idea what to monitor and have also developed the tools they require. They can also be an “interface between the industry and regulators,” says Thompson. What they need now is an action plan – and money to get on with it. The Scottish Government has made renewables a strategic priority and is funding research “more than most other countries,” but when the industry starts putting more devices into the water, the scientists want to be ready to study their impact – and share their research with the world.
Dr Beth Scott
Dr Beth Scott is a Senior Lecturer in the School of Biological Sciences at the University of Aberdeen. As a marine ecologist, she is chiefly interested in “predator–prey interactions,” modelling and simulating the behaviour of seabirds, including where and how they feed, and what will change when more marine renewable devices are deployed.
Research: Scott has a multi-disciplinary background in marine ecology and oceanography and her research investigates the functional linkages between fine-scale biophysical oceanographic processes and the specific characteristic of different marine habitats (i.e. small-scale turbulence at the edges of banks) where predator and prey species overlap (when and where transfer of energy up the food chain actually happens).
Research goals: This work helps to quantify the type of vertical habitat that seabirds and mammals like to use to capture their prey – e.g. fast and turbulent water. If we can quantify those values, we can develop physical models to predict what changes lots of turbines will cause to the water column, nearby and also miles downstream. This will help us to predict how much energy can be extracted before it may interfere with predators capturing prey.
Priorities: We need to know exactly how animals are capturing prey in these high-energy environments and understand how the introduction of turbines and wave machines will affect those interactions. To do this, we need instruments on the sea bed (such as upward- facing acoustic sonar) and around real machines that can capture second-by-second information on predator and prey movement. This information will also allow us to calculate collision risks and learn more about the environmental effects of large-scale developments, helping regulators be sure they can safely give licences, as well as lowering investment risks.
Dr Gordon Hastie
Dr Gordon Hastie is a Research Fellow at the University of St Andrews Sea Mammal Research Unit. His research interests focus on the potential impacts of human activities (including marine renewable devices, sonar, vessels and pile driving) on marine mammals. In particular, he is interested in how marine mammals use sound in their everyday lives to navigate, find prey and avoid predators, and how noise produced by man might affect this. To address these questions, he has used a range of novel research techniques, including tracking animals around tidal turbines using imaging sonar, or measuring movements of seals during the construction of an offshore wind farm using GPS tags that are attached to the animal's fur.
Dr Ruairi Maciver
Dr Ruairi Maciver is a Research Fellow at Lews Castle College, University of the Highlands and Islands (UHI). His research interests are the hydrodynamics of coastal environments and the interactions with marine renewables.
Research: His knowledge of coastal flows has been developed through mathematical and physical modelling studies of the interaction between waves and currents, the evolution of turbulence, and the forces experienced by structures located in such flows. He is applying this knowledge to the marine renewables sector to quantify the flow characteristics in the presence of marine renewable energy devices. Understanding how devices influence the physical environment is a key aspect of predicting how marine renewable energy developments will affect the biological environment.
Priorities: A campaign of flow-field measurements in regions that will host the first arrays of devices must be undertaken before and after deployment. Numerical models are powerful tools that can evaluate many scenarios. However, to ensure confidence in their output, they must be calibrated and validated against measurement. Establishing accurate and properly calibrated models will permit regulatory bodies to assess the environmental impact of future developments with confidence.
Dr Ben Wilson
Dr Ben Wilson is a Senior Lecturer and Principal Investigator in Mammalogy and Marine Renewables at SAMS (the Scottish Association for Marine Science) in Oban, and a Marine Energy Theme Leader at MASTS. He is interested in the impact of marine renewables on marine mammals, and “what it’s like to be predator and prey in these highly energetic and challenging habitats.”
Research: Wilson's work focuses on developing tools and methods to work in high-energy marine environments. Before renewables came along, most researchers would avoid such energetic seas, but now there is a real need take the plunge, he says. Some monitoring methods can simply be applied with modification, whilst others need to be completely rethought/redesigned and tested to destruction. Using these tools, his team is beginning to uncover just how species such as porpoises are exploiting these dynamic spots.
Priorities: With the impending deployment of energy devices into our most energetic coastal waters, there’s an urgent need to understand why large predators are already using these areas and how they might interact with our industrial activities. If there are conflicts, we will need to understand them before we can fix them, so properly monitoring what goes on around the first marine devices is vital.
Professor Paul Thompson
Professor Paul Thompson is Head of the University of Aberdeen’s Lighthouse Field Station in Cromarty. He is a population ecologist, using long-term individual-based studies to explore how environmental variation influences the behaviour, physiology and dynamics of marine mammal and seabird populations.
Research: These long-term studies have provided unique opportunities for research on interactions between offshore energy developments and marine mammal populations. Recent work has focused on understanding responses to underwater noise, and developing assessment frameworks that have been used to support consenting decisions for offshore wind farms.
Priorities: The longer-term population consequences of behavioural disturbance remain extremely uncertain. Consequently, assessment frameworks have had to be based upon a number of critical assumptions, particularly those linking an individual’s exposure to noise with subsequent changes in reproduction or survival. Focused research around the next generation of large-scale developments is now required to test these assumptions. This should be underpinned by individual-based studies, which will allow the importance of these man-made stressors to be assessed in relation to the broader suite of drivers that can shape population dynamics.