The role of tidal asymmetry in characterizing the tidal energy resource of Orkney

2014 ◽  
Vol 68 ◽  
pp. 337-350 ◽  
Author(s):  
Simon P. Neill ◽  
M. Reza Hashemi ◽  
Matt J. Lewis
2020 ◽  
Author(s):  
Vera Fofonova ◽  
Alexey Androsov ◽  
Lasse Sander ◽  
Ivan Kuznetsov ◽  
Felipe Amorim ◽  
...  

<p> </p><p>The study is dedicated to the tidal dynamics in the Sylt-Rømø Bight with a focus on the non-linear processes. The FESOM-C model was used as the numerical tool, which works with triangular, rectangular or mixed grids and is equipped with a wetting/drying option. As the model’s success at resolving currents largely depends on the quality of the bathymetric data, we have created a new bathymetric map for an area based on recent studies of Lister Deep, Lister Ley, and the Højer and Rømø Deep areas. This new bathymetric product made it feasible to work with high resolution grids (up to 2 m in the wetting/drying zone). As a result, we were able to study the tidal energy transformation and the role of higher harmonics in the domain in detail. The tidal ellipses, maximum tidally-induced velocities, energy fluxes and residual circulation maps were constructed and analysed for the entire bight. Additionally, tidal asymmetry maps were introduced and constructed. The full analysis was performed on two grids with different structures and showed a convergence of the results as well as fulfillment of the energy balance. The tidal residual circulation and asymmetric tidal cycles largely define the circulation pattern, transport and accumulation of sediment and the distribution of bedforms in the bight, therefore the results are necessary and useful benchmarks for further studies in the area, including baroclinic and sediment dynamics investigations.</p>


Author(s):  
Chris Rose ◽  
Peter Melchett

This chapter deals with three linked issues. First, the nature of modern campaigning, with particular reference to the work of Greenpeace and the solutions they offer. Second, the role of Greenpeace and other nongovernmental organizations from the not-for-profit sector. Third, the challenge and opportunities created by ‘globalization’ and what this means for global governance from an environmental point of view. For some years Greenpeace has argued that ‘solutions’ have moved to centre stage in the work of pressure groups, as they used to be known. The formative role of environmental campaigning organizations was to draw attention to problems, but by the 1990s, finding and demonstrating solutions, and getting them applied, became much more important (see Yearley, this volume). This has proved a long and hard road. Indeed, the gap between what can be done and what is being done has, if anything, widened. This is mainly because the technical potential has improved while, in Britain at least, implementation has moved much more slowly. It was once famously said of an incompetent British government that this is an island built on coal and surrounded by fish, but still it manages to run out of both. Similar things could be said today. The government has patently failed to protect fish stocks but that can be conveniently blamed on the EU Common Fisheries Policy. But no such excuse will wash on energy. Britain’s wave energy resource is more than 70 times the UK electricity demand. Britain’s wind resource is also vast. Offshore wind could meet Britain’s entire electricity demand three times over. Against this, the government’s unattained target of 10 per cent for renewable electricity is simply pathetic. Contrast Britain with Denmark, which is phasing out fossil fuel use in electricity generation and is on course for generating 50 per cent of its electricity from wind alone by 2030. Little wonder Denmark is reaping the benefits in terms of engineering jobs in wind turbines, an industry in which it is world leader. The story in Germany and the Netherlands is similar: yet Britain is far, far windier.


2020 ◽  
Vol 8 (6) ◽  
pp. 411
Author(s):  
Zhaoqing Yang ◽  
Taiping Wang ◽  
Ziyu Xiao ◽  
Levi Kilcher ◽  
Kevin Haas ◽  
...  

Numerical models have been widely used for the resource characterization and assessment of tidal instream energy. The accurate assessment of tidal stream energy resources at a feasibility or project-design scale requires detailed hydrodynamic model simulations or high-quality field measurements. This study applied a three-dimensional finite-volume community ocean model (FVCOM) to simulate the tidal hydrodynamics in the Passamaquoddy–Cobscook Bay archipelago, with a focus on the Western Passage, to assist tidal energy resource assessment. IEC Technical specifications were considered in the model configurations and simulations. The model was calibrated and validated with field measurements. Energy fluxes and power densities along selected cross sections were calculated to evaluate the feasibility of the tidal energy development at several hotspots that feature strong currents. When taking both the high current speed and water depth into account, the model results showed that the Western Passage has great potential for the deployment of tidal energy farms. The maximum extractable power in the Western Passage was estimated using the Garrett and Cummins method. Different criteria and methods recommended by the IEC for resource characterization were evaluated and discussed using a sensitivity analysis of energy extraction for a hypothetical tidal turbine farm in the Western Passage.


2015 ◽  
Vol 112 (13) ◽  
pp. 4158-4163 ◽  
Author(s):  
Nelcy Thazar-Poulot ◽  
Martine Miquel ◽  
Isabelle Fobis-Loisy ◽  
Thierry Gaude

Lipid droplets/oil bodies (OBs) are lipid-storage organelles that play a crucial role as an energy resource in a variety of eukaryotic cells. Lipid stores are mobilized in the case of food deprivation or high energy demands—for example, during certain developmental processes in animals and plants. OB degradation is achieved by lipases that hydrolyze triacylglycerols (TAGs) into free fatty acids and glycerol. In the model plant Arabidopsis thaliana, Sugar-Dependent 1 (SDP1) was identified as the major TAG lipase involved in lipid reserve mobilization during seedling establishment. Although the enzymatic activity of SDP1 is associated with the membrane of OBs, its targeting to the OB surface remains uncharacterized. Here we demonstrate that the core retromer, a complex involved in protein trafficking, participates in OB biogenesis, lipid store degradation, and SDP1 localization to OBs. We also report an as-yet-undescribed mechanism for lipase transport in eukaryotic cells, with SDP1 being first localized to the peroxisome membrane at early stages of seedling growth and then possibly moving to the OB surface through peroxisome tubulations. Finally, we show that the timely transfer of SDP1 to the OB membrane requires a functional core retromer. In addition to revealing previously unidentified functions of the retromer complex in plant cells, our work provides unanticipated evidence for the role of peroxisome dynamics in interorganelle communication and protein transport.


2017 ◽  
Vol 20 ◽  
pp. 1-16 ◽  
Author(s):  
Maricarmen Guerra ◽  
Rodrigo Cienfuegos ◽  
Jim Thomson ◽  
Leandro Suarez
Keyword(s):  

Energy Policy ◽  
2014 ◽  
Vol 68 ◽  
pp. 92-101 ◽  
Author(s):  
L.J. Bracken ◽  
H.A. Bulkeley ◽  
C.M. Maynard
Keyword(s):  

2015 ◽  
Vol 75 ◽  
pp. 626-639 ◽  
Author(s):  
M. Reza Hashemi ◽  
Simon P. Neill ◽  
Peter E. Robins ◽  
Alan G. Davies ◽  
Matt J. Lewis

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