With rapid growth in the wind energy industry, the demand for wind turbines is increasing throughout the world, including regions subject to extreme climatic conditions. LTi REEnergy has produced PITCH system solutions to meet the challenges of offshore, cold and hot climates. This article describes the company's cold climate version (CCV) of the PITCH system.

The NewGen is a new type of direct-drive generator for wind turbines, based on the idea of putting the generator bearings adjacent to the air-gap of a large diameter generator. In this way the stiffness requirements of the rotor and the stator are drastically reduced, which leads to large mass savings in the mechanical structure.  These savings then enable a further diameter increase, which leads to further mass reductions in electrically active parts. The design is based on excitation by use of permanent magnets. So far a 140kW pilot-scale generator has been tested with encouraging results. The next step is a full-scale demonstration in a wind turbine. The development is taking place in cooperation with VG Power AB, Vasteras, Sweden.

By Staffan Engström, Independent Consultant, Agir Konsult AB, Sweden

Wind energy remains the front-runner in the increased use of renewable energy. In the quest for cost-efficient wind energy, the constant availability of strong winds is crucial for every project. This is why, after coastal regions and high mountains, it is important to explore, develop and install near-shore and offshore wind projects. The first 2MW onshore turbines suffered from transformer reliability concerns around 2002. The problems due to vibrations, electric switching surges and overloading were investigated and designs were changed accordingly. Since 2004, step by step, wind energy has increasingly moved offshore.  Again, some reliability concerns were discovered and equipment was replaced. This article summarises the need for higher specifications and more reliable transformers in order to prepare the wind industry business for sustainable growth in offshore multi-megawatt turbines.

Accessing offshore wind turbines is critical to keep all systems running. This is especially true when the weather deteriorates, wind speeds pick up and production can be maximised. But offshore these conditions also mean that wave heights increase and access by boat can become impossible. The Ampelmann has been developed to increase the accessibility from a ship, even in high wave conditions. The system uses six hydraulic cylinders (also used in flight simulators) to support a transfer deck and gangway. By measuring the ship motions continuously and controlling the length of the cylinders, the transfer deck stands completely still compared to the wind turbine. Access to the turbine then becomes 'as easy as crossing the street'.