Enercon has installed more than 15,000 wind energy converters with a power of 18.5 GW

Enercon came into being when company founder Aloys Wobben had an idea: In the wind energy converters of the time, rotor and generator turned at a fixed speed because they had to adapt their power feed to the 50 Hz frequency of the power grid. The grid determined the rotational speed. However, wind turbines produce more energy, if they can adjust their rotational speed to the wind speed. Wobben’s idea was to use a converter to transform the variable frequency of the generator and thus adapt it to the grid. This makes it possible to decouple WEC and grid, and the WEC can adjust its rotational speed.

In 1984, Aloys Wobben and a small team manufactured the frequency converters needed for turbine yawing in a former carpet warehouse in Aurich in Northwest Germany. As the WEC manufacturers of the day were unwilling to take up the idea of grid decoupling, Aloys Wobben decided to press on with the development of his own WEC. One year later, the first E-15 turbine with 55 kW of rated power was erected near the home of the company‘s founder. This machine, with some modifications, is still in operation today: Apart from the converters, it consisted entirely of supplied parts.

“The Flüger furniture store in Norddeich and the municipal utilities in Norderney and in Norden were our first customers in the region. In the first year of production, we made five turbines; in the second year, twenty,” remembers Klaus Peters, who has been with ENERCON from day one and is now Overall Production Manager. Company founder Wobben was the only person back then who was convinced that one day, they would build 1000 machines per year.

Switching to direct drive technology

The zero series production allowed ENERCON to gain valuable experience. The biggest source of problems turned out to be the gearbox with oil leaks and gearwheel breakages. As a result, the decision was taken to dispense with this component completely. After years of intensive development, the first gearless WEC was built in 1992: An E-36 turbine, the precursor of the E-40 that would soon be widely sold. At the same time, options were explored to reduce the load on the rotor, resulting in the introduction of adjustable rotor blades that can rotate around their own axes to turn out of the wind when necessary.

In parallel, manufacturing capacities were expanded. The most successful approach proved to be the in-house production of those components for which a satisfactory supplier could not be found on the market. When no annular generators of the required size existed in the early 1990s, ENERCON began to develop their own generators. Because the efficiency of the conventional rotor blades left to be desired, the company designed their own optimised rotor blade shapes and set up a series production facility.

In the course of the 1990s, ENERCON fully industrialised their wind energy converter production. Milestones included the begin of E-40 series manufacturing in Aurich (1993); the first international production facilities in India (1995) and Brazil (1996); as well as the acquisition of machine engineering company SKET (1998) based in Magdeburg in Eastern Germany, which constituted the breakthrough to large-scale series production.

By now, development had progressed to the E-66/1.8MW. With SKET, ENERCON acquired a formering GDR large-scale enterprise. After a brief period of cautious probing on both sides – SKET had had bad experiences in earlier takeovers – a synergetic relationship evolved that combined the strengths of two different company cultures: SKET came with great experience in large-scale industrial projects, ENERCON contributed its innovative spirit and flexibility. Manufacturing capacity doubled within just one year, positioning the company perfectly for the wind turbine boom that started after the turn on the millennium, not least thanks to the amended German Renewable Energy Sources Act.

Growing production capacities and technology advances

Even during the years of growth in which a lot of energy was directed towards expanding production capacities, ENERCON never lost sight of the advancement of their product design and technology. The development focus lied on the introduction of the new rotor blade design for all turbine types; the enhancement of power electronics; the continued differentiation of the model range; and the widening of the range of application of gearless turbine technology.

At the end of 2007, the most powerful WEC to date made its appearance in the ENERCON product offering: The E-126 with 6 MW of rated power. In addition, ENERCON developed their own fuel-efficient cargo ship for transporting WECs, with an innovative sail rotor propulsion system and optimised hull and propeller shapes. The company has also been active in the fields of hydropower and seawater desalination, and the supply of wind-diesel systems that provide an efficient and environmentally-friendly electricity supply in stand-alone systems.

Culture of innovation

ENERCON’s success is founded on a culture of innovation that permeates all parts of the company from research & development to manufacturing, where engineers are constantly looking for ways to improve products and processes and to implement ideas that create solutions. The company also manages to strike the right balance between bringing in outside expertise and relying on home-grown skills for filling management positions. And since the knowledge required for creating cutting-edge WEC technology needs to be passed on to the next ENERCON generation, the company training policy has been exemplary right from the start. Currently, it is offering apprenticeship opportunities in 20 different vocations.

At the end of the day, ENERCON also owes its growth capacities to the high customer satisfaction, which in turn is founded on the high technical availability and the proven reliability of ENERCON’s WEC technology.