Production for ENERCON

Impressive production network

All main components of ENERCON wind energy converters – such as annular generators, inverters, rotor blades, cast components, towers and machine houses – are produced at factories operating exclusively for ENERCON. This means ENERCON ensures optimum quality control, stays independent and also reduces the risk of losing expertise. The feedback of experience from production to product development is also of great importance.


Consistent expansion of production network

In accordance with this entrepreneurial decision, ENERCON has been systematically expanding its network of exclusive suppliers in Germany and abroad since the early 1990s. Industrialisation of manufacture is part of the production policy for the plants producing exclusively for ENERCON. This finds expression in the form of ultra-modern and efficient production facilities and in the use of industrial robots, for example. The high quality and labour safety standards that are partially clearly stricter than the Health & Safety inspectorate’s and liability insurance associations’ requirements are also outstanding. 

Generator production

The annular generator is a key component of ENERCON’s gearless wind energy converter design. The ENERCON annular generator is a multi-polar synchronous generator manufactured by the generator plants that produce exclusively for ENERCON at the German sites in Aurich and Magdeburg and the Portuguese site Viana do Castelo. Since ENERCON annular generators have been designed for particularly high stress and a long service life, they are impregnated with resin and powder-coated in subsequent manufacturing steps to protect them against corrosion. The annular generators are completed for delivery at the final assembly factories that work exclusively for ENERCON.

Final assembly

The machinery and plant engineering companies that work exclusively for ENERCON are in charge of the final assembly of annular generators, hubs and machine houses. As well as at the German sites in Aurich and Magdeburg, final assembly is also carried out – primarily for export – in Viana do Castelo in Portugal. In the final assembly the large components are completed in efficient line production, they are subjected to a functional test and finally made ready for shipment. The individual work steps are performed at several stations in the assembly line.


ENERCON is the only wind energy converter manufacturer in the world to have a foundry that produces exclusively for the company. Gusszentrum Ostfriesland GmbH (GZO) at Georgsheil (Lower Saxony) produces mainly rotor hubs, main carriers, axle pins and stator shields for the megawatt-class ENERCON WECs. ENERCON only accepts highest quality standards for these load-carrying spheroidal graphite cast components. A pioneering quality assurance system in which all production steps are monitored and documented is the quality guarantee at GZO.

GZO is one of the most modern foundries in Europe. The production is performed according to the series and line production principle. Mould making, casting and subsequent cast processing are located in separate areas. Labour safety and environment protection measures are also groundbreaking and clearly above the standard in the branch. Efficient filter plants clean the waste air, self-propelled transporters move the moulds in the danger areas. The cast blanks are subsequently transported by the rail company e.g.o.o. mbH for further processing in Aurich and Magdeburg.

Stanztechnologie providing punching technology

Stanztechnologie Aurich GmbH (STA) is a supplier that works exclusively for ENERCON for the generator production. The segment and pole sheets needed for the production of ENERCON’s annular generators are punched out of special electric strips.

Besides the highly automated production processes, the recycling concept at STA is exemplary for ENERCON’s demands for a modern production: Chads are collected automatically in containers and transported to the foundry GZO. The chads are recycled there in the casting of WEC components

Rotor blade production

ENERCON’s rotor blade concept sets the benchmark with regard to yield, noise emission and load minimisation. The same applies to the production of these main components that has been carried out by factories producing exclusively for ENERCON since the 1990s.

Most of ENERCON rotor blades are manufactured using a vacuum infusion system with the so-called sandwich technique. Glass fibre mats placed in the mould are vacuum-impregnated with resin by means of a pump and hose system. In order to efficiently protect the rotor blade surface against weather elements such as wind and water, UV radiation, as well as erosion and bending loads, the rotor blades’ protective finish is composed of gel coat, filler, edge protection and top coat.

Optimised line production in connection with more efficient production logistics was implemented in rotor blade manufacture for the first time at the main rotor blade factory, Kunststofftechnologie Aurich GmbH (KTA). Following the model of the automotive industry, the moulds are moved from one work station to the next at the exclusive ENERCON manufacturing plant. Exactly defined work steps are carried out at every work station. The production of small parts has been relocated to the upper floor of the factory from where they are directly lowered into the moulds in the blade manufacturing process. Laying of glass matting during the production of the spar booms and gluing of the half shells proceeds automatically.

After the blade blank has been removed from the mould, it is traversed to another hall part where the mechanical treatment of the blade surface and of the blade connection takes place. Industrial robots are mainly used for this hard work. After the so-called finish where the rotor blades are given their protective coating and where they are subsequently balanced, also by robots, they are delivered to the installation site or to the export port in Emden.

Tower production (concrete/tubular steel tower)

Hybrid towers for ENERCON wind energy converters comprise individual precast concrete elements and steel sections that form the top end of the tower. Concrete segments with large diameters are produced in two or three shells so that they can also be transported to locations which are complex to reach. After all segments and sections have been assembled, the bottom steel section, the concrete segments and the foundation are joined together and tensioned to form one unit by means of prestressing tendons.

The precast concrete segments are produced under strict quality control measures at one of the exclusive ENERCON concrete tower plants located as close to the installation site as possible. The high level of manufacturing precision is guaranteed through the use of special steel moulds with very low tolerances. Detailed procedure instructions and work procedure instructions are provided for each production area. This ensures that each individual work step can be completely retraced, as well as the materials and tools used. To guarantee optimum quality, the properties of the high-strength concrete are also tested by specialised material testing authorities.

Abnormal load trucks deliver the segments to the installation site. At the site the divided segments are bolted together and placed one on top of the other using the installation crane. The precisely pre-fabricated horizontal joint allows the tower to be quickly assembled under diverse weather conditions.

ENERCON tubular steel towers are produced in several tower sections, connected via stress-reducing L-flanges. Unlike conventional flange joints, the welding seam of the L-flange lies outside the stress zone. Manufacturing takes place at steel tower and WEC assembly suppliers that produce exclusively for ENERCON.

ENERCON tubular steel towers are connected to the foundation by means of a specially developed foundation section or a foundation basket.

Like all other components, tubular steel towers are subject to strict ENERCON quality standards. Quality assurance is already integrated in the development of new tower types in the design stage, to ensure that the prototype meets all requirements before going into serial production.

Energy for the world

ENERCON GmbH - Dreekamp 5 - D-26605 Aurich