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Injury and mortality of fish during downstream passage through hydropower turbines is among the leading direct impacts of hydropower. Understanding the relationships among various strike variables and injury and mortality rates are necessary for improvements in turbine design. We subjected three species of fish to simulated blade strike in laboratory studies with different blade thicknesses,…

The need for an environmentally sustainable alternative to fossil-sourced energy has led to a global increase in offshore renewable energy (ORE) ventures in the past decade. With fast-advancing technologies, these ventures are moving into deeper waters, putting the likelihood of ORE installations in the High Seas in sight. Concerns about potential conflict with other traditional uses of the…

Collisions, shear events and barotrauma are severe causes of fish mortality in a hydroelectric turbine. Fish-adapted turbine management and environmentally enhanced turbines can be mitigation measures. To use those measures efficiently, knowledge about turbine mortality is needed. In this study, a combination of CFD modelling, fish passage modelling and mortality assessment was used to…

Despite losing its low-carbon energy transition path in the last decade, Spain, since 2017, has picked up its commitment to complying with the objectives set out in the Paris Agreement for ratcheting 2030 and 2050 ambitions. This research departs from an extensive in-depth expert stakeholder engagement, proposing a research process of scoping: reaching out to academics, NGOs, administrators,…

Nova has been conducting environmental survey and monitoring activity in Bluemull Sound, Shetland since November 2010. Initial environmental surveys were carried out to gather information in support of consent applications for Nova’s existing turbine deployments in Bluemull Sound. Following turbine deployments, the focus of environmental monitoring shifted to activity required under the…

The environmental impact of deploying ocean energy devices has to be considered during all stages of a project’s development and operation – from the drawing board, to the site selection and to the active management of the devices’ performance.

With little real data collected so far, it is difficult to make plans, strategies and adjustments to minimise possible environmental impacts.…

Tidal-stream turbines are a promising source of renewable electricity worldwide. These technologies are sufficiently new that only single test devices have been deployed with arrays imminent. Being new, their interactions with marine organisms are poorly understood and the risk of large marine vertebrates colliding with their moving blades is a consenting and ecological concern.…

Tidal energy has the potential to form a key component of the energy mix of a number of countries, including the UK. Nonetheless, the deployment of tidal energy systems is associated with potential environmental impacts as prime resource sites often coincide with unique ecosystems inhabited by sensitive organisms. Preceding studies have generally focused on the hydrodynamic impact of tidal…

This report draws on the body of environmental assessment work done on marine renewable energy installations (MREI) in other regions, particularly in Europe, and summarized in a companion report – Ecology and Effects of Marine Renewable Energy Installations. A combination of several techniques is required in order to appropriately monitor marine megavertebrate species around tidal turbine…

Background

This document provides a Non-Technical Summary (NTS) of the Environmental Statement (ES) produced in support of Sea Generation (Kyle Rhea) Limited’s consent application for the Kyle Rhea Tidal Stream Array (‘the Project’). The ES is the formal report of an Environmental Impact Assessment (EIA) undertaken by impartial environmental consultants Royal Haskoning and subcontracted…

Steam-electric power plants drawing cooling water from surface waters entrain a variety of plankton and weak-swimming nekton. These small organisms pass through the intake screens and are carried along with the cooling water through the plant and are subjected to thermal, physical, and chemical (biocide) stresses. In once-through cooling systems, entrained organisms are returned to the source…

Interest in ocean energy converter technology has increased with the revival of renewable energy awareness. To date, ocean current energy converters have been implemented with relatively mature technology when compared to wave energy converters. Despite the novelty of wave energy, several commercial wave energy projects have recently been undertaken. However, this process has not been…

Marine renewable energy (MRE) devices potentially impact dynamics of aquatic organisms including macroinvertebrates, fish, seabirds, and marine mammals. Understanding potential impacts of MRE technologies on biological communities requires knowledge of species-specific spatial and temporal density distributions. Acoustic technologies capable of providing images and data for baseline…

Generating electricity from waves is predicted to be a new source of renewable energy conversion expanding significantly, with a global potential in the range of wind and hydropower. Several wave power techniques are on the merge of commercialisation, and thus evoke questions of environmental concern. Conservation matters are to some extent valid independent of technique but we mainly focus on…

Islands energy systems are often separated from mainland energy markets. Islands routinely rely on a single imported source of energy, which exposes islands to economic risks, and an increased likelihood of system failure. Integrating renewable energy into island energy systems can provide diversity of energy supply and improved system efficiency, potentially yielding cheaper energy for island…

Research in natural products has advanced tremendously through the fields of chemistry, life, food and material sciences. Comparisons of natural products form microorganisms, lower eukaryotes, animals, higher plants and marine organisms are now well documented. Natural products are ubiquitous in our everyday lives. They are active constituents of many medicines, vitamins, food additives,…

Blue whales (Balaenoptera musculus) are distributed worldwide, and although severely depleted by commercial whaling, their abundance off the California coast now appears to be increasing. Little is known about natural causes of mortality of blue whales, but human-related mortality continues despite legal protection. Ship strikes are a significant mortality factor for other species of baleen…

This paper seeks to identify promising sites and technologies, in Portugal, for co-located wave energy conversionand offshore aquaculture, whilst providing benchmark implementation references and guidelines to researchers. Accordingly, two case study sites are considered for deployment of five wave energy devices and up to six aquaculture species. A thorough analysis in terms of power ratios,…

It is often claimed that marine renewable energy alone could meet the electricity demand of current and future human societies. However, such claims are based on highly uncertain estimations of the global potentials of marine renewable energy sources (including tidal, ocean currents, wave, offshore wind and salinity and thermal gradients), and do not take into account the embedded energy of…