Marine renewable energy: potential benefits to biodiversity? An urgent call for research

Abstract

Summary 1.The evidence for anthropogenically induced climate change is overwhelming with the production of greenhouse gases from burning fossil fuels being a key driver. In response, many governments have initiated programmes of energy production from renewable sources. 2. The marine environment presents a relatively untapped energy source and offshore installations are likely to produce a significant proportion of future energy production. Wind power is the most advanced, with development of wave and tidal energy conversion devices expected to increase worldwide in the near future. 3. Concerns over the potential impacts on biodiversity of marine renewable energy installations (MREI) include: habitat loss, collision risks, noise and electromagnetic fields. These factors have been posited as having potentially important negative environmental impacts. 4. Conversely, we suggest that if appropriately managed and designed, MREI may increase local biodiversity and potentially benefit the wider marine environment. Installations have the capacity to act as both artificial reefs and fish aggregation devices, which have been used previously to facilitate restoration of damaged ecosystems, and de facto marine-protected areas, which have proven successful in enhancing both biodiversity and fisheries. 5. The deployment of MREI has the potential to cause conflict among interest groups including energy companies, the fishing sector and environmental groups. Conflicts should be minimized by integrating key stakeholders into the design, siting, construction and operational phases of the installations, and by providing clear evidence of their potential environmental benefits. 6. Synthesis and applications. MREI have the potential to be both detrimental and beneficial to the environment but the evidence base remains limited. To allow for full biodiversity impacts to be assessed, there exists an urgent need for additional multi and inter-disciplinary research in this area ranging from engineering to policy. Whilst there are a number of factors to be considered, one of the key decisions facing current policy makers is where installations should be sited, and, dependent upon site, whether they should be designed to either minimize negative environmental impacts or as facilitators of ecosystem restoration.

Coastal and Offshore Wind Energy Generation: Is It Environmentally Benign?

“…Much interest has been placed on turbine underwater structures functioning as artificial reefs and FAD [18,21]. For example, a study in the Adriatic Sea proposed a beneficial link between offshore wind farms and bluefin tuna [15].…”

“…From the conservation view, this may cause the fish community to return to their original (pre-anthropogenically-altered) condition and is consequently perceived as beneficial. However, it may also cause further deviation from the reference community natural to the area and may be considered undesirable [18].…”

“…The nature and complexity of man-made structures influence assemblages of benthic crustaceans more than fish [19,20]. Enhancement of the structures with features such as holes and artificial seagrass beds have been proposed to increase complexity and microhabitat choice, measures that are considered to increase the ecological value of artificial hard substrata and have positive effects on the complexity of the resulting fish assemblage [10,18].…”

Mutually-Beneficial Renewable Energy Systems

“…At the level of individual installations, marine renewable energy systems may be used to limit fishing and recreation, increase the surrounding density of some fish species, and provide fish aggregations devices, new spawning grounds and nursery areas (Inger et al 2009;BirdLife Europe 2011;Copping et al 2016). Ocean energy facilities can be integrated within broader marine planning efforts to support marine ecosystems and biodiversity (Copping et al 2016;Hammar et al 2017).…”

Simulating environmental changes due to marine hydrokinetic energy installations

“…Because water circulation patterns may change, the residence times (flushing rates) may also change, potentially changing algae growth patterns as well as concentrations of nutrients and dissolved gasses [4]. Acoustic energy and electromagnetic waves emanating from MHK devices and infrastructure may perturb wildlife behavior or vary the ecosystem [5,6]. Holistically these factors may modify biological dynamics, intrude upon migration paths, disturb life cycles and communication, or alter resource availability.…”