The offshore wind industry is expanding rapidly around the world due to several factors enabling this source of renewable energy. Stronger wind resources in offshore areas, lack of social and geographical constraints related to onshore wind power, the evolution of technology, and increasing demand for electricity in coastal regions as a result of a massive increase in population are some of the factors favoring the use of wind energy. The assessment of the potential global capacity that considers the different economic, environmental, and social factors and the dynamics of market, policy, and technology are vital for estimating the competitiveness of offshore wind energy in the future energy profile. There are several studies and technical reports that evaluate the potential of offshore wind energy in different countries or regions. They used a different source of data, metrics, and quantitative approaches in appraising the potential offshore wind power capacity and its cost efficiency. The critical factors that have been considered are geographical, technical, economic, environmental, and social and market elements. This paper provides a systematic review for analyzing the studies that address the potential offshore wind energy around the world and published during the 2000–2016 period. This study highlights the key criteria for assessing the potential for offshore wind energy deployment and the related tools and methods.
Coastal and Offshore Energy
Competing usage of marine space has prompted several coastal nations to implement marine spatial planning (MSP). While progressive governments promote the deployment of renewable energy technologies (RETs) in order to meet renewable energy capacity and greenhouse gas emissions reductions targets, offshore RETs become another player operating within a finite and already stressed marine environment. This paper applies the sectoral MSP process employed by Scotland to the Nova Scotia context in order to draft a MSP for the province's tidal energy sector. Applicable legislation is reviewed in order to establish the regulatory authorities with powers to plan for both the marine development and ecosystem protection agendas. The scoping process identifies suitable resource areas based on the operational parameters of commercially viable tidal current turbines (TCTs), while the sustainability appraisal identifies areas of cultural, industry, ecological, and socioeconomic constraint and exclusion. Plan option areas emanating from the applied methodology demonstrated a 238.345 km2 (98.1%) increase in suitable TCT deployment area than the marine renewable energy areas identified in Nova Scotia's Marine Renewable Energy Act which did not undertake such a methodology.
The Canary Islands, as many islands and coastal regions, are characterized by no conventional energy sources (but renewable resources, mainly wind and solar), by a high population density and land scarcity. Taking into account this context, it is crucial to determine the offshore wind energy potential as a first step for the energy planning. For this purpose, a methodology adapted to islands’ and coastal regions’ requirements has been developed. The methodology is based on GIS (Geographical Information Systems), and takes into account technical, economic and spatial constrains. Wind turbines (bottom-fixed or floating according to the bathymetry) are placed within the resulting suitable areas, quantifying also the energy production and its cost. The economic analysis includes the calculation of the LCOE (Levelized Cost Of Energy), including integration costs, and the resulting resource cost curves. The methodology has been applied to a practical case, the Canary Islands. Results show that the electricity produced by offshore wind farms exceeds the yearly electricity demand. Moreover, the offshore wind energy cost is lower than the current electricity cost. The analysis provides further useful indicators such as percentage of suitable areas, surface covered by wind turbines, array density of turbines and marginal offshore wind energy cost.
Wind turbines continuously remove kinetic energy from the lower troposphere, thereby reducing the wind speed near hub height. The rate of electricity generation in large wind farms containing multiple wind arrays is, therefore, constrained by the rate of kinetic energy replenishment from the atmosphere above. In recent years, a growing body of research argues that the rate of generated power is limited to around 1.5 W m−2 within large wind farms. However, in this study, we show that considerably higher power generation rates may be sustainable over some open ocean areas. In particular, the North Atlantic is identified as a region where the downward transport of kinetic energy may sustain extraction rates of 6 W m−2 and above over large areas in the annual mean. Furthermore, our results indicate that the surface heat flux from the oceans to the atmosphere may play an important role in creating regions where sustained high rates of downward transport of kinetic energy and thus, high rates of kinetic energy extraction may be geophysical possible. While no commercial-scale deep water wind farms yet exist, our results suggest that such technologies, if they became technically and economically feasible, could potentially provide civilization-scale power.
Proponents of marine renewable energy worldwide highlight that regulatory and consenting procedures are a significant barrier to the upscaling of infrastructure required to transform the energy generation sector. Uncertainties about the cumulative effects of marine renewable energy developments cause substantial delays during the consenting process, which are exacerbated by the lack of clarity about how to assess cumulative effects. These obstacles have contributed to perceptions that this essential emerging industry receives disproportionate scrutiny relative to established maritime activities. However, alongside legislated targets to reduce carbon emissions, there are legal obligations to protect, maintain and improve the condition of the marine environment. As the imperative to halt the decline in the condition of the environment increases, so expectations of cumulative impact assessments grow and the risk of consenting delays persists. To investigate how robust current cumulative impact assessment practise is, a novel evaluation framework was developed and applied to Environmental Statements of the world's largest offshore wind farms, currently in United Kingdom waters. The framework was designed to evaluate cumulative impact assessments relative to the information needs of decision-makers tasked with managing cumulative effects. We found that current practise does not meet those needs, that there is dissonance between science and practise, and problematic variability between assessments was observed. Straightforward recommendations for improved practise are provided, which if implemented may ease the perceived regulatory burden by clarifying practise. We also highlight additional steps that could enable project-led cumulative impact assessments to better support regional marine management. The results and recommendations will be of interest to countries worldwide where marine renewable energy is emerging alongside ecosystem-approach and marine spatial planning aspirations.
At present, there is no specific legal basis for the development and utilisation of marine renewable energy, nor legal protection for the developers in China. The consequence is that the Chinese Government is unable to provide institutional support for the substantive development of marine renewable energy, resulting in slow development of China's marine energy industry. This paper provides an institutional framework for the establishment of relevant laws in China and legislative proposals in legal perspective, for the better development of marine renewable energy. The Chinese Government should optimise the administrative management system, strengthen financial regulation such as tax and emphasise sustainable development.
Marine tidal-stream renewable energy devices (MREDs) are beginning to move from demonstration to early commercial deployment. However, the ecological impacts which may result when large arrays of these devices are deployed are unknown. This uncertainty is placing a considerable burden on developers who must collect biological data through baseline and post-deployment monitoring programs under the Environmental Impact Assessment process. Regulators and other stakeholders are often particularly concerned about impacts on marine vertebrates (fish, seabirds and mammals) because many of these receptors are of high conservation and public concern. Unfortunately monitoring for most marine vertebrates is challenging and expensive, especially in the energetic waters where tidal-stream MREDs will be deployed. Surveys for marine vertebrates often have low statistical power and so are likely to fail to detect all but substantial changes in abundance. Furthermore, many marine vertebrate species have large geographical ranges so that even if local changes in abundance are detected, they cannot usually be related to the wider populations. Much of the monitoring currently being undertaken at tidal-stream MRED development sites is thus leading to a ‘data-rich but information-poor’ (DRIP) situation. Such an approach adds to development costs whilst contributing little to wider ecosystem-based understanding. In the present article we discuss the issues surrounding the impacts of tidal-stream MREDs on marine vertebrates and address the questions regulators, developers and other stakeholders need to consider when agreeing monitoring programs for these receptors.
The excessive combustion of fossil fuels for energy provision have altered natural planetary functions, resulting in adverse biophysical and societal implications. Such implications have prompted many governments globally to advocate for the adoption of renewable energy systems in order to reduce GHG emissions. While renewable energy technologies such as solar and biogases have been thoroughly researched and deployed, tidal current turbines (TCTs) that harness kinetic energy from the lateral movement of the tides are a comparatively emerging renewable energy technology, and thus has received relatively less attention with respect to their potential to supplement the renewable energy transition. This paper examines the physics behind tidal movements and cycles, and the technological operation of TCTs. Environmental impacts and economic barriers are analyzed. Best practices of MSP from world leading nations are examined, along with current deploy-andmonitor-consenting regimes of TCT test facilities. An optimal TCT design is suggested based on a synthesis of information from proceeding sections. Finally, an analysis of the implementation of TCTs in Canada, China, and Norway is presented, the results of which demonstrate that harnessing the accessible and sustainably extractable resource of each nation can result in an aggregate installed capacity of 9076 MW through the deployment of 7564 TCTs at a cost of $5,740,964,430, thereby creating 14,467 jobs. This would produce 29,829,711 MW h/yr of electricity sold at approximately 22 cents/kWh, eliminating a total of 14,914,855,258 kg of CO2e, approximately 0.1%. of the projected global electricity demand for 2016.
The objective of this paper is to present a method that qualifies the degree of visibility of an offshore wind farm from an observer located along the coast. In many cases, the deployment of an offshore wind farm leads to public opposition. This entails the need for the development of appropriate methods that might present in the most intelligible way the impacts of an offshore wind farm. Amongst many factors to take into account, the visual impact of such farms is surely a factor to take into account. We introduce a visual operator that integrates several parameters that mainly depend on the distance of the wind farm to the coast. We apply a measure that evaluates the horizon surface impact modulated by the number of distinguishable turbines and an aesthetic index based on turbine alignments. The whole method is implemented on top of Geographical Information System (GIS) and provides a decision-aid mechanism oriented to decision-makers. The whole approach is experimented in the context of a wind farm in North West France.
National-scale polls demonstrate high levels of public support for developing renewable energy while local opposition has led to delays and cancelations of renewable energy projects around the world. What makes for robust public engagement processes to reject or site renewable energy projects? A literature review reveals numerous considerations, with complexity that impedes their application by practitioners. In this study, we conducted interviews and document analysis to assess the extent to which design principles from the analytic-deliberative process literature arose during public engagement on three New England islands adjacent to proposed offshore wind farms. In our study sites—amongst the array of criteria in the literature—good public engagement boiled down to two key themes: enabling bidirectional deliberative learning and providing community benefit. Decision processes perceived as effective occurred when (1) participants, including experts and local stakeholders, learned from each other while reconciling technical expertise with citizen values; and (2) outcomes included the provision of collaboratively negotiated community benefits. Our findings highlight that community benefits are not the same as benefits to groups of individuals. Attending to these key themes may improve the quality of interactions among communities, government authorities and developers when deciding if and where to site renewable energy infrastructure.