- Category: Articles
Strength and Fatigue Experiments and Modelling
The wind turbine rotor is an important part of the connection between the moving air (containing the wind energy) and the generator (used to capture this energy). The rotor consists of (usually) three blades, which are almost entirely made of fibre-reinforced plastic. These blades experience a large number of load cycles during their economic life. The magnitude of the load cycles is not at all constant. The rotor materials and structure need to withstand all these loads, great and small. Extensive research is devoted to predicting strength and life for rotor blades. For this research, numerous tests are done, exposing small fibre-reinforced coupons (specimens) to realistic loading conditions. Based on this data, fatigue models can be made predicting blade life. But, of course, ‘the proof of the pudding is in the eating'. Full-scale blade tests are required to see if reality matches expectations.
By Rogier Nijssen, WMC, The Netherlands
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The wind turbine rotor is an important part of the connection between the moving air (containing the wind energy) and the generator (used to capture this energy). The rotor consists of (usually) three blades, which are almost entirely made of fibre-reinforced plastic. These blades experience a large number of load cycles during their economic life. The magnitude of the load cycles is not at all constant. The rotor materials and structure need to withstand all these loads, great and small. Extensive research is devoted to predicting strength and life for rotor blades. For this research, numerous tests are done, exposing small fibre-reinforced coupons (specimens) to realistic loading conditions. Based on this data, fatigue models can be made predicting blade life. But, of course, ‘the proof of the pudding is in the eating'. Full-scale blade tests are required to see if reality matches expectations.
By Rogier Nijssen, WMC, The Netherlands
- Category: Articles
Can this Concept Ever Leave the Cradle of Innovation?
Offshore wind turbine technology is being pushed into deeper offshore locations. This is sometimes because of pressure from environmental lobbying or sometimes because of geographical restrictions, such as in the case of Malta, a Mediterranean island with limited space and resources.
Offshore wind turbine technology is being pushed into deeper offshore locations. This is sometimes because of pressure from environmental lobbying or sometimes because of geographical restrictions, such as in the case of Malta, a Mediterranean island with limited space and resources.
- Category: Articles
Quantifying the Risk for Offshore Wind Farm Developments
The marine renewables energy sector is an emerging force in energy provision globally and recent announcements by the UK government have created ambitious targets for the domestic market. In the UK it is driven principally by the Energy White Paper (2003) and, more specifically, by the Renewables Obligation, which requires electricity suppliers to source 15% of their supply from renewable sources by 2015, increasing to 20% by 2020. There is more than 1GW of projects with planning consent waiting to be built, and a second round of offshore tenders from The Crown Estate, with a total of 7.2GW, is awaiting application - equivalent to 7% of UK electricity requirement. There are plans for a 2,000 turbine, 10GW wind farm in the North Sea, the largest in European waters, which would supply energy to 8 million homes.
By Kevin Black, Partrac Ltd, UK
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The marine renewables energy sector is an emerging force in energy provision globally and recent announcements by the UK government have created ambitious targets for the domestic market. In the UK it is driven principally by the Energy White Paper (2003) and, more specifically, by the Renewables Obligation, which requires electricity suppliers to source 15% of their supply from renewable sources by 2015, increasing to 20% by 2020. There is more than 1GW of projects with planning consent waiting to be built, and a second round of offshore tenders from The Crown Estate, with a total of 7.2GW, is awaiting application - equivalent to 7% of UK electricity requirement. There are plans for a 2,000 turbine, 10GW wind farm in the North Sea, the largest in European waters, which would supply energy to 8 million homes.
By Kevin Black, Partrac Ltd, UK
- Category: Articles
Underground Pumped-Storage Hydropower Station
In today's world it is essential to recover more and more energy from sustainable sources. This, and the need for a reliable supply of electrical energy at all times, creates a demand for systems that match a variable energy production with the energy demand pattern. This article presents such a system.
By A.F.M. van Velsen, Royal Haskoning, The Netherlands
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By A.F.M. van Velsen, Royal Haskoning, The Netherlands
- Category: Articles
Advances in Textiles for Vacuum Infusion Processing
Wind power's portrayal as a 100% clean source of renewable energy bodes well for those seeking a power source with little environmental impact. Nevertheless, to stay true to this green promise, we mustn't lose sight of the carbon footprint laid down prior to the generation of electricity. Composite materials, acknowledged as an enabler of the green promise, can contribute greatly to this footprint. In recognition of this reality, manufacturers' have turned from open mould processing to closed mould vacuum infusion processing.
By Patrick Mack, Chief Technologist, Polynova Composites, USA
- Category: Articles
The Effects of Rolling Element Bearing Stiffness on Wind Turbine Planetary Gearbox Dynamics
This article details the effect of including accurate stiffness models of rolling element bearings in the dynamic simulation of planetary wind turbine gearboxes and discusses the frequently neglected subject of bearings' contribution to the dynamic behaviour of turbine gearboxes.
By Richard Dorling, Romax Technology, UK
- Category: Articles
Floating, Autonomous, Environmentally Friendly and Efficient Desalination Unit
Global warming is an emerging threat to water availability and to the quality of life in isolated island communities in southern Europe. Isolated small islands in the Mediterranean region already experience the problem of scarce water sources during the dry summer period. Climate change is likely to further aggravate this situation in the coming years and therefore alternative water sources have to be investigated in these areas.
By Theodore Lilas and Nikitas Nikitakos, University of Aegean, Department of Shipping Trade and Transport, and Anthanasios Vatistas, ECOWINDWATER Ltd, Greece