• Energy Research
• OA Publications Mandate: No close
• 2016 close

One problem when we are trying to field super-big wind turbines is that all components involved become super heavy as well, particularly power generators. Heavier power generators require more robust foundation towers for support, which dramatically increase the cost of the entire system. The project is to investigate approaches of lightening up the next generation of utility scale turbines to generate 10 MW peak power. The major aim of this project is to develop a new compact superconductor-based generator able to work in both onshore and offshore wind turbines. Based on previous research work, it was proven that the weight when compared to conventional power generators could be reduced by at least 30% by applying superconductors. However, further work is required to analyse and improve the existing design; such as in regards to the superconducting windings and the cryogenic cooling system. The final objective is to build a 15kW prototype to prove the feasibility of the new lightweight power generator.

This is a PhD research project in mechanical engineering, more specifically in floating offshore wind turbine aerodynamics. The impact on the aerodynamic performance of the rotor as the platform moves in the wind direction will be investigated using computational fluid dynamics. The scenarios considered will be those with platform motion high enough to enter the turbine into propeller state and vortex ring state, two events that can lead to a significant reduction in the turbine's performance as a result of the turbine interacting with its own wake.

Sustainable energy production is a critical challenge faced by mankind currently and one that will persist in the coming decades. Production of electricity from sunlight is a key technology in the global search for a solution to this problem. Current photovoltaic technologies, especially silicon-based photovoltaics, are widely deployed, however concerns remain over the ability of solar to compete with traditional electricity generation in a truly free market. To this end, secondary and tertiary photovoltaic technologies at the forefront of research are focused on low-cost production methods while at the same time reaching and maintaining the high efficiencies currently on the market. One current exciting approach taken by research is that of quantum dot photovoltaics. By creating nanoparticles out of semiconductor materials, quantum effects cause the band gap to increase and shift relative to their position in the bulk material. This can be harnessed to convert a larger proportion of sunlight into electricity, and to expand the catalog of suitable photovoltaic materials. Quantum dots can be made at low cost, and their small size allows them to be used in printing technologies for low cost, large area device processing. Of paramount importance to this technology is the separation of these quantum dot nanoparticles, aggregation in close proximity causes the particles to interact in such a way as to destroy their quantum properties. To prevent this, large organic ligands are attached to the quantum dots during their synthesis. These large organic ligands are then exchanged for smaller ones during device production, and different ligands can affect the position and size of the band gaps in quantum dots. Currently, the ligands used to ensure a uniform dispersion of the quantum dots do not contribute to the performance of the photovoltaic device beyond separating the quantum dots and modifying their band gaps. In fact, we believe that the insulating layer of ligands hinders the movement of charges within the device by providing large barriers to electron tunneling between the dots, preventing the charge from leaving the device and reducing efficiency. This research aims to improve device efficiency by using ligands that provide a smaller barrier to electron tunneling. We aim to use ligands with conjugated double bonds commonly seen in plastic electronics and organic photovoltaics. This should make it easier for electrons to tunnel out of the dots, improving charge transport within the device and subsequently its efficiency. EPSRC's research area is Energy

Awaiting Public Project Summary

One of the major current scientific and technological challenges concerns the conversion of carbon dioxide to fuels and useful products in effective and economically viable manner. This proposal responds to the major challenge of developing low energy routes to convert carbon dioxide to fuels and useful chemicals. The project has the following four main strands: (i) The use of electricity generated by renewable technologies to reduce CO2 electrocatalytically, where we will develop new approaches involving the use of ionic liquid solvents to activate the CO2 (ii) The use of hydrogen in the catalytic reduction of CO2, where we will apply computational procedures to predict new materials for this key catalytic process and subsequently test them experimentally (iii) The development of new materials for use in the efficient solar generation of hydrogen which will provide the reductant for the catalytic CO2 reduction (iv) A detailed life cycle analysis which will assess the extent to which the new technology achieves the overall objective of developing low carbon fuels. Our approach aims, therefore, to exploit renewably generated energy directly via the electrocatalytic route or indirectly via the solar generated hydrogen in CO2 utilisation for the formation of fuels and/or chemicals. The different components of the approach will be fully integrated to achieve coherent, new low energy technologies for this key process, while the rigorous life-cycle analysis will ensure that it satisfies the need for a low energy technology.

Conventionally designed wind turbines only operate efficiently in steady, uninterrupted air. However, most users want to access wind in urban areas or near industrial units where the nature of the wind is more turbulent and swirling. Conventional designs do not work efficiently with the swirling, variable nature of wind at such sites. In this project Swift Energy present a radical re-design of a vertical axis wind turbine, with key technological improvements that will allow efficient operation in small-footprint, urban sites. Such sites have the added advantage that they are close to consumers, minimising transmission losses. WindSurf is a vertical axis, active pitching wind turbine. Swift's patented control technology uses servomotors to continually alter blade pitch, which allows self-starting in wind speeds as low as 3m/s, and optimised energy capture in free and turbulent wind streams. Edinburgh's role in this project is to produce an optimised design of the electrical generator for the WindSurf rated at 16kW, taking into account the environment in which it will be operating. A direct drive generator will be used to eliminate the gearbox, which will improve reliability and efficiency. Both of these contribute to LCOE: reliability through increased availability and reduced OPEX; and improved efficiency will enhance annual energy yield. An air-cored permanent magnet generator will be designed and built that is optimised for the structure of the Swift wind turbine. In order to achieve such an optimised design an integrated design approach is required, which links electromagnetic design, with structural design and thermo-fluid design. Edinburgh has built up 10 years of experience in the integrated design of direct drive permanent magnet air-cored generators for wind and marine renewable energy applications. Air-cored machines eliminate undesirable magnetic attraction forces that try to close the gap, and thus this topology benefits manufacture, assembly and structural design. A vertical axis wind turbine allows the electromagnetic design of the machine to have a large diameter, out near the blades. A large diameter will result in high airgap velocity and thus have a positive impact on torque density (Nm/kg), reducing the amount of active material, which is the most expensive part of the machine. A novel structural arrangement will be developed for integration into the turbine, which where possible makes best use of the existing structural material, again to minimise material usage and thus cost. A modular design approach will be adopted to ease manufacture and assembly of the generator, but also to make O&M easier. By positioning the generator close to the blades, we will investigate we will investigate methods of "scooping" air from the turbine onto the generator to assist with cooling. Effective cooling will benefit the torque density and the overall performance of the machine. Numerical modelling tools will be used in the design process, such as ANSYS for structural analysis, StarCCM for thermo-fluid analysis, and Infolytica for electromagnetic design. An existing analytical design tool will be refined based on the structural and CFD modelling in order to assist SWIFT in the future design and production of their turbine. Multi-body modelling using SIMPACK will be combined with structural modelling to investigate the impact of environmental loads on the generator in terms of airgap deflection. Once the design is finalised, the machine will be built under subcontract to Fountain Design Ltd, with whom we have worked in the past to build prototype generators. The machine will be tested at the University of Edinburgh on its wind-emulator test rig to verify performance and the design tools developed. A thorough integrated design approach with manufacturing and production techniques in mind supported by laboratory testing will ensure that SWIFT can move towards commercialisation.

This project fits squarely within the EPSRC's Energy theme (Solar Technologies and Materials for Energy Applications) and is overlapping with the Physical Science and manufacturing the future themes. This project will focus on the development of transparent electrodes based on nano-structured ultra-thin metal films, matched to the needs of the emerging generation of organic and perovskite photovoltaics. The project will focus particularly on chemical approaches to stabilizing these electrodes towards oxidation in air and the development of new chemical approaches to achieving large area patterning of these electrodes. The project will span electrode fabrication and characterisation (including optical modelling), as well as photovoltaic device fabrication and characterisation, and so represents a truly inter-disciplinary research training opportunity.

Photovoltaic (PV) devices convert sunlight directly into electricity and form an increasingly important part of the global renewable energy landscape. Today's PVs are based on conventional semiconductors which are energy-intensive to produce and restricted to rigid flat plate designs. The next generation of PVs will be based on very thin films of semiconductors that can be processed from solution at low temperature, which opens the door to exceptionally low cost manufacturing processes and new application areas not available to today's rigid flat plate PVs, particularly in the areas of transportation and buildings integration. The emerging generation of thin film PVs also offer exceptional carbon dioxide mitigation potential because they are expected to return the energy used in their fabrication within weeks of installation. However, this potential can only be achieved if the electrode that allows light into these devices is low cost and flexible, and at present no electrode technology meets both the cost constraint and technical specifications needed. This proposal seeks to address this complex and inherently interdisciplinary challenge using three new and distinct approaches based on the use of nano-structured films of metal less than 100 metal atoms in thickness. The first approach focuses on the development of a low cost, large area method for the fabrication of metal film electrodes with a dense array of holes through which light can pass unhindered. The second approach seeks to determine design rules for a new type of 'light-catching' electrode that interacts strongly with the incoming light, trapping and concentrating it at the interface with the semiconductor layer inside the device responsible for converting the light into electricity. The final approach is based on combining ultra-thin metal films with ultra-thin films of transparent semiconductor materials to achieve double layer electrodes with exceptional properties resulting from spontaneous intermixing of the two thin solid films. The UK is a global leader in the development of next generation PVs with a growing number of companies now focused on bringing them to market, and so the outputs of the proposed programme of research has strong potential to directly increase the economic competitiveness of the UK in this young sector and would help to address the now time critical challenge of climate change due to global warming.