Power & Energy Solutions

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Just over 60 years ago, on March 26, 1949, the Fraunhofer-Gesellschaft was founded in the large conference hall of the Bavarian Ministry of the Economy. At the time, the idea was to develop new structures for research after the war's destruction, and to spur reconstruction of the economy. Today, the globally-respected institute analyses current macro trends and identifies fields of research that will play a particularly important role in the future in meeting challenges such as climate change, dwindling resources and preventive healthcare. Wind energy is firmly on the agenda. PES presents an exclusive Fraunhofer research paper.There's a fair wind blowing for wind energy: Europeans invested 13 billion euros in new turbines in 2007. Tens of thousands of wind turbines are already in operation, and more are being planned. To keep them working reliably, interdisciplinary teams are developing new technologies for construction, quality assurance and maintenance. For the turbines to actually produce the theoretically calculated outputs, they must be in perfect technical condition. Even small material defects can have devastating consequences. The inspection of the components, above all, the 70-meter long rotor blades, is a science in itself. Fraunhofer engineers in Bremerhaven specialise in the oversized material and

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The certification of wind turbines or components is state-of-the-art and a must in most places around the world. Furthermore, certification to harmonised requirements is an active support of export. Therefore it is important for manufacturers, banks and insurances of wind turbines and components to know the different certification processes as well as guidelines. This exclusive feature for PES puts focus on a new approach of combined design and certification of wind turbines, where an intense collaboration between the turbine designer or manufacturer and the certification body is proposed at an early stage of the turbine development.The benefits of this approach, known as Development Accompanying Assessment (DAA), includes reduced time-to-market and improved product quality.IntroductionCertification of wind turbines has a history of 30 years. It has been applied differently in scope, requirements and depth in countries like Denmark or Germany and each on the basis of their own rules. These countries are still leading in the development and application of certification rules but during recent years a number of other countries as well as many banks realised the necessity of a thorough evaluation and certification of wind turbines and their proposed installation. Among these countries are China, Greece, India, Spain, Sweden and

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The continent's first electricity grid for renewable power has become a political reality, as nine countries formally link clean energy in a deal worth €30bn. For the wind industry, in particular, it will mark perhaps the final step towards mainstream acceptance.The North Sea Grid is the big idea as far as renewable energy generation across Europe is concerned. Several years in the planning, and now ratified by an agreement between nine European countries, this is the first stage in a so-called 'supergrid' is aimed squarely at the development of a single European market for renewable energy.The "supergrid" is expected to decentralise energy provision, connect sources of renewable energy and drive down bills from energy suppliers. Naturally, wind power features extensively in the development of the supergrid, with expectations for the plans to increase the potential of offshore wind farms and hydropower to supply electricity to consumers across the continent.Paolo Berrino, of the European Wind Energy Association, said: "The North Sea grid will connect offshore wind to our electricity supply, enabling Europe to exploit its largest untapped energy source. It will allow trade in electricity between countries, thereby bringing more competition into the market and reducing electricity prices."The network, made up

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As long ago as 1995, a German study reported that more than 80% of insurance claims for damage to wind turbines were paid as result of lightning strikes. A little thought will reveal that this is not particularly surprising. Wind turbines are tall structures and their blades have a small radius of curvature at their tips, which encourages the build up of electrical charge and, therefore, increases their vulnerability to lightning.At the time the study was carried out, the largest wind turbines had a generating capacity of around 150 kW. The corresponding figure today is 6 MW. This increase in generating capacity has necessarily been paralleled by an increase in the physical size of the turbines - whereas 60 m high was once the norm, heights in excess of 160 m are now common, and even taller structures are not unknown.The risk of wind turbines suffering lightning strikes today is, therefore, even greater than it was in 1995. And, in fact, that risk is in many cases further increased by the locations that are typically favoured for the siting of wind turbines. These include open land, coastal regions, mountain ridges and offshore, all of which mean that the turbines are

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IntroductionThe current economic crisis sparked by the credit crunch of 2008 has had a significant impact on renewable energy markets. As a result of the global economic downturn, the lending market has contracted, making securing financing for renewable energy projects dramatically more difficult than in the past. Equity investors have in turn become fewer.Despite this unfavourable environment for investors and against all expectations, the wind energy industry enjoyed another record year in 2009 with 37.5 GW installed globally. This figure represents a year-on-year growth of 27%, bringing the cumulative installed capacity to over 150 GW. Though the offshore market made up only approx. 2% of total installations, the 620 MW this sector added represents a growth of 80%.The top five nations for installed capacity were China, US, Spain, Germany and India, which, when combined, accounted for nearly 75% of the installed capacity in 2009. For the first time, 2009 saw the European market overtaken by the Asian and North American markets, which combined accounted for 58% of new installations in 2009.In parallel with this impressive industry growth, demand for electricity is projected to increase by an annual average rate of 2.5% between 2007-2030; much of this will come from developing

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For offshore wind turbines, taking every possible step to reduce the risk of mechanical breakdown is mission-critical. With a raft of unique application challenges and constant concern around efficient use of funding for wind farm management, engineering reliable, productive up-time into the wind energy sector will be no easy task. And for off-shore turbines, with the extra costs associated with maintaining assets some 20 miles from land, reliability and durability are a particular focus.A leading manufacturer of high precision gearing products and services, David Brown has been providing engineering expertise to a range of heavy duty process industries, rail and critical defence applications worldwide for 150 years. The company is developing this sovereign foothold into a specialism for swift, effective and reliable engineering in the fast-growing wind turbine industry, understanding that such gearbox malfunctions cost wind farm operators dearly in terms of downtime and replacement/repair expenditure.The David Brown team is quickly building a reputation as a leading independent inspector of end-of-warranty wind turbines. Here Erik Roeloffzen, Design Analyst within that team, identifies ten typical failure modes taken from his unique experience and advises how to avoid them:The problem: fatigue and normal wearFatigue damage and regular wear of moving parts

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Dr Eddie O'Connor, CEO of Mainstream Renewable Power, recently gave a thought-provoking and wide-ranging speech to a meeting of the Institute of International and European Affairs. Here for PES, he reiterates some of the major concerns and prophecies of that speech.To begin with here, I take it as a given that we humans have to go on containing the rise in global temperatures to less than two degrees Celsius by 2050 or risk triggering irreversible and catastrophic damage to our planet.I also take it as an absolute imperative that by 2050 we will have to reduce our Greenhouse Gas emissions (GHG) by 80% at a time when the generation of electricity is predicted to rise by at least 100%. The first figure, of an 80% GHG reduction comes from the UN International Panel on Climate Change, while the second figure comes from the International Energy Agency, which is part of the OECD.That 80% reduction in GHG emissions, while power generation is being doubled is no little challenge, which can realistically only be met if we replace hydro-carbons with Renewable Energy. Pursuing this logic, the only form of Renewable Energy which is capable of commercial deployment on the scale and at

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