Wind Power

Automation Speeds Up Turbine Production

Issue 4 and Volume 1.

Nordex has modernised its European production centre in Rostock in order to significantly improve the efficiency and production quality of the plant. In doing so it is continuing a trend toward automation in the wind industry, which is broadly equivalent to the changes that resulted in the mechanisation of the automotive industry nearly a century ago.

Nordex has converted its nacelle and switch cabinet factory to continuous flow production. The results of this modernisation are standardised work processes and shorter throughput times, making it possible to triple capacity in the two-shift operation from 330 to around 1,000 turbines a year. This equates to output of 2,500 MW. Nordex has also reduced the production time and rotating stock by some 30 percent. Throughout time has fallen from 13 days to just five days.

Overall, Nordex has set up three lines for the main components — the nacelle, hub and drive train — and three further lines for pre-assembly. The company decided in favour of a rail system with friction wheel drive. For this the technology had to be adapted to the existing hall layout. The most suitable solution proved to be a skid system with an angular transfer unit designed to take heavy weights. For construction of the switch cabinets the skids are moved by a drag chain conveyor. In this way Nordex has converted the entire nacelle assembly to continuous flow.

A Low-vertical Integration Approach

Nordex is taking a low-vertical integration approach to supply chain management, says CEO Dr Marc Sielemann, whose own background is in the automotive industry. “In the early stages (of windmill production) the supply chain might not be developed so you may do things you otherwise wouldn’t, but in the long run nobody can be the best at everything. Someone who is best in the decathlon won’t win the 100 metrers and so we are building a team of highly professional partners, each belonging to the best in their sphere.”

But this new technology is only one part of the changeover. The organisational changes made are of key importance. For example, dock assembly made it difficult to determine the actual production status and the picture presented by the production hall was that of rows of shelves full of material. Now the assembly lines are designed in accordance with the principle of synchronisation and the required material is available directly at the assembly station — Nordex has minimised its stock-keeping and moved it out of the hall. “We’ve invested around €4 million but only around €1.7 million of that is in new machinery,” says Sielemann.

Fixed contract amounts have been replaced by rolling forecast and the staged call off principle whereby the delivery schedule is organised according to a series of flexible release steps. “We found (when building a gearbox) that the hard part the supplier had was ordering bearings, but the with the changes we’ve made the supplier can build up an inventory of bearings,” says Sielemann, adding that Nordex is now 95 percent accurate in terms of its demand schedule.

While new technology has improved production, organisational changes are key to effective modernization (Source: Nordex)

On top of this, large screens now inform all staff about progress in the respective cycle and along the entire production line. Any disruptions in the assembly process are immediately evident and can be remedied in good time. This minimises downtimes and error rate.

“For the efficiency programme in our production division we were able to adopt many principles from other industries,” said Sielemann. “We attached particular importance to transparency and organised trouble-shooting as they make it possible for us to continuously optimise production.”

“We built the most modern truck plant in Europe,” says Sielemann, “and now we have built the most modern turbine plant in Europe.”

Sielemann says that having a modern facility brings additional benefits throughout the company.

“In the old days, people would finish one turbine then celebrate by drinking beer and having a barbecue but things have moved on from there. Line production now forces discipline on other parts of the organisation. For example, in the past suppliers would say ‘two days more or less’ but now it has to really work and we can also do better TCO evaluations. Buying the cheapest might not turn out to be the best given the recurrent problems it could cause in production.”

Sielemann also stresses the need for what he calls “visual transparency.” He says, “The state of the factory is now apparent to everybody at every point in time. Additional markings on the floor show the place for material. Boards, cards and lights show the state of processes. Performance is measured and tracked on team boards.”

Sielemann believes that further mechanisation will be an ongoing trend in wind energy. “The idea of changing our production came up two years ago and that was one of the reasons why I joined Nordex — because we needed to industrialise our processes. We are not the first but we are the most thorough,” says Sielemann.

“It’s not about the techniques of production, there’s no secret about the technical side, it’s the organisational side that’s tougher,” says Sielemann. “We’re more focused on team meetings, key learning and that kind of thing. When I worked for MAN I saw that Toyota had invented a way of organising production into three key areas: line assembly, relationship with suppliers and continuous improvement in shop floor management. That’s what we are trying to achieve at Nordex. We’ve already integrated this system at our factories in Arkansas and in Rostock but not yet in China.”

Modernisation across the Sector

Nordex is not the only company in the sector that sees the necessity to modernise its production processes in order to lower costs and remain competitive.

Back in 2006 when the wind power industry was being squeezed by a turbine shortage, the largest manufacturer of turbines in the world, GE Energy, announced advances in its production chain that could help squeeze out a few more turbines to help meet robust worldwide demand. In Germany, GE Energy’s wind business has opened a new 80-tonne wind turbine “moving line” in its Salzbergen manufacturing facility to help to meet increased global demand for turbines.

GE’s moving line is a 42-meter rail system on which the turbines are continuously moved during production. It was designed for the manufacture of both GE 1.5 and multi-megawatt wind turbines and offered a 30 percent increase in capacity along with quality and safety improvements.

GE says the efficiency of the line enabled it to increase its capacity by 30 percent while reducing its inventory by 40 percent at the Salzbergen plant. A key feature of the line is its capability to detect abnormalities should they occur in wind turbine assembly, and to halt the manufacturing process until the issues are resolved. It can move at various speeds to accommodate different output levels.

The introduction of stable and standardised processes forms the basis of reliable deliveries to customers and guarantees high-quality products (Source: Nordex)

But while GE set the pace, the rest of the field is eager to catch up. Doosan Power Systems, part of the Korean industrial conglomerate Doosan Heavy, is the new kid on the block. The Korean company has unveiled plans to develop a 6-MW offshore-specific turbine. It plans to develop the turbine in order to enter the European market, where the company says it has identified a significant opportunity by 2020.

Doosan says it has decided to aggressively step up its campaign to industrialise its wind power business. The company also says it plans to co-develop core parts, including blades, with local small and medium-sized enterprises.

It currently offers a geared 3-MW wind turbine product, first developed in 2004 and commercially launched towards the end of 2010, although currently this is mainly for its domestic market. In September 2009, Doosan installed a prototype machine in Gimnyeong, Jeju Island where the island’s autonomous government is aggressively supporting the development of wind energy technology.

While the conceptual specification of the new 6-MW machine is complete, Doosan says it is currently finalising both the technical details of the system as well as options for manufacturing and assembly. Scotland is one option being favourably considered with groundbreaking anticipated in 2012.

An on-site pilot prototype is due to be installed by the end of 2013 and this will be followed in 2014 by prototype and demonstration units offshore, likely comprising three to four machines. Currently, the company foresees commercial series production in 2015. However, it is also in discussion with its partners with a view to exploring an option to accelerate the development programme by a full year. In addition, it is open to the concept of jointly developing pilot schemes with utility partners.

Already, Doosan and Scottish Enterprise have agreed to enter into a Memorandum of Understanding that will likely see the company locate its R& D Centre of Excellence for Renewables at its current site at Westway in Renfrew, near Glasgow. A second phase will advance a further proposal for the establishment of assembly and manufacturing facilities in Scotland — now the company’s favoured location for wind turbine prototype-build and manufacturing.

Meanwhile, the Danish wind turbine manufacturer Vestas says it will invest approximately €10 million in the next two years in Viveiro in Lugo in order to establish local production of generators.

The factory in Viveiro was chosen due to its existing skilled workforce that will enable Vestas to manufacture generators, one of the main components in a Vestas turbine. It is planned that the new factory will directly support the production capacity of the nacelle factory in Leon, which is currently under extension. When the investment is completed, the factory in Viveiro will produce 2 MW generators required for the V90 2 MW turbine.

But Vestas is also looking to move the centre of its operations eastwards to where many believe the new heart of Europe’s wind industry now lies, given a combination of generous operator subsidies, enthusiastic government support and an abundance of wind.

Vestas has installed over 20 wind turbines in Romania and recently opened its Eastern European hub in the capital Bucharest. The opening of a local production factory may follow. “Like any market production is determined by demand,” says Andrew Hilton, vice president of communications. “Vestas has the correct capacity for the current market demand. As markets grow we always consider if there is a business case for setting up local production, hence our recently announced plans for a factory in the U.K. As developing markets like Romania mature we will be looking to find local suppliers in areas where we see development potential.”

GE Energy is also making its presence felt out East. The energy behemoth supplied 240 wind turbines to the CEZ Group for the 600-MW Fantanele project in Romania, Europe’s largest onshore wind project. In Poland, 110.5 MW of wind energy capacity has been installed, comprising 21 2.5-MW turbines and 39 1.5-MW turbines. In April GE announced its first wind farm project in Bulgaria, developed with local partner the Winslow Group and expected to generate up to 69 MW of power.

An Emerging Market

Magdalena Dziegielewska, research analyst for energy and power systems at Frost & Sullivan, states that the overall market for wind farm components in Eastern Europe is just beginning to take shape. “The first visible signs of growth are seen in foundry and welding sectors. However, these components are mostly produced for wind farms located in Eastern Europe.”

The benefits work both ways, says Dziegielewska. “[Eastern European] companies also participate in Western European projects, however they are usually sub-contractors for local firms and provide work related to painting and welding of steel parts.”

With regards to projects in Eastern Europe she believes Western European suppliers are using local firms to make substantial cost savings. “Due to the significant size of components and high transportation costs that vary from €60–€80 per kilometre manufacturers are looking for sub-contractors and sub-suppliers among local producers,” she explains.

Looking to the future, there is clearly the potential for major wind turbine manufacturers to operate manufacturing bases in Eastern Europe, especially if markets like Romania and Poland continue their impressive growth.

Modernisation around the World

Outside Europe, factories in the US are also looking to modernise their production facilities. Spanish firm Gamesa Wind, the number two producer of wind turbines worldwide, has aggressively ramped up production of its wind turbines at an abandoned US Steel plant in Bucks County, Pennsylvania in order to enter the U.S. alternative energy market. The plant is now capable of producing two 300-foot tall steel and carbon fibre wind towers every day. One year’s production output has the potential energy generating capacity of 700 MW.

Working closely with state and local economic development and regulatory agencies, the site was ready for initial production within six months. Renovating an existing building in a timely manner was critical to meeting the market window for Gamesa products. As with Nordex in Rostock, Gamesa chose to recycle a brownfield site, thereby saving on the costs of constructing a new building entirely from scratch.

Another noteworthy project in terms of automation is WinWinD Power Energy’s manufacturing facility at Vengal, not far from Chennai, in India. The Vengal facility will assemble and test nacelle hubs and produce rotor blades, and will initially manufacture utility grade 1-MW (WWD-1) wind turbines. The plant has an initial production capacity of four wind turbine generators per day (12 blades) and going forward, the company plans to scale up capacity to eight (24 blades) per day.