A considerable body of research is currently being performed to quantify available tidal energy resources and to develop efficient devices with which to harness them. This work is naturally focussed on maximising power generation from the most promising sites, and a review of the literature suggests that the potential for smaller scale, local tidal power generation from shallow near-shore sites has not yet been investigated. If such generation is feasible, it could have the potential to provide sustainable electricity for coastal homes and communities as part of a distributed generation strategy, and would benefit from easier installation and maintenance, lower cabling and infrastructure requirements and reduced capital costs when compared with larger scale projects. This article reviews tidal barrages and lagoons, tidal turbines, oscillating hydrofoils and tidal kites to assess their suitability for smaller scale electricity generation in the shallower waters of coastal areas at the design stage. This is achieved by discussing the power density, scalability, durability, maintainability, economic potential and environmental impacts of each concept. The discussion suggests that tidal kites and range devices are not well suited toward small-scale shallow water applications due to depth and size requirements, respectively. Cross-flow turbines appear to be the most suitable technology, as they have high power densities and a maximum size that is not constrained by water depth. Oscillating hydrofoils would also be appropriate, provided comparable levels of efficiency can be achieved.

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This article is focused on numerical analyses of commercially available metal-oxides as potential nano-additives for paraffin in thermal storage applications. Technical and economic prospects of metal-oxides based nano-PCMs are evaluated to help formulate selection criterion for nano-additives to achieve optimum thermal performance at acceptable cost. Numerical model based on enthalpy-porosity technique is developed which incorporates natural convection and transient variations in thermo-physical properties of nano-PCM. Numerical model is simulated for charging and discharging cycles of nano-PCMs in shell and tube heat exchanger at controlled temperatures. Transient simulations help in analysing heat transfer categorisation and isotherms distributions, solid-liquid interfaces propagations, charging and discharging rates, and overall thermal enthalpy. Inclusion of nano-particles increase the effective thermal conductivity and surface area for heat transfer, which results in enhanced charging and discharging rates. The conductive heat transfer, peak heat flux, charging and discharging rates are significantly enhanced by increasing volume concentration of nano-particles. The percentage enhancement in charging rates of SiO 2 based nano-PCM samples with 1% and 5% are 29.45% and 41.04%, respectively. Likewise, the discharging rates are improved by 21.09% and 30.08%, respectively. However, an increase in volume concentration reduces natural convection and overall thermal enthalpy, and increases total cost of nano-PCM. For instance, the percentage reductions in total enthalpy of CuO based nano-PCM samples with 1% and 5% volume concentrations are 8.01% and 32.14%, respectively. Likewise, the total costs are increased from 14.26 €/kg for base paraffin to 70.89-309.33 €/kg, respectively. Hence, the significance and originality of this research lies within evaluation and identification of preferable metal-oxides with higher potential for improving thermal performance at reasonable cost. This article will help bring significant impact to large-scale utilisation of low-carbon and clean energy technology in domestic and commercial applications.

The purpose of this paper is to investigate the role of lower-limb running prostheses and stakeholders’ perceptions of fairness in relation to their use in competitive disability sport. A Delphi study was conducted over three rounds to solicit expert opinion in a developing area of knowledge. High levels of consensus were obtained. The findings suggest that the prosthesis is defined as a piece of sporting equipment to restore athletes’ function to enable them to take part in disability sport. In addition, the panel determined that the development of this technology should be considered to be integral to the sport’s ethos. Crucially, prostheses technology should be monitored and have limits placed upon it to ensure fairness for both participants and stakeholders.