Keeping the nights bright...
7 kilometres off the southern coast of Sweden lies Vattenfall's offshore wind farm Lillgrund, one of the largest in the world. Experts from Pöyry have served as consultants from planning to operation.
The choice of location in the Sound was crucial when the project started. The middle has the optimum conditions, with regular strong winds and an average wind speed of 8.4 m / s at a height of 64 metres. At an early stage a wind mast was placed at the site to make it possible to perform wind measurements for accurate wind analysis and production calculations.
Lillgrund is located only seven kilometres from the Swedish mainland and there were great local concerns about environmental impact, including the noise from the wind turbines. To minimise Lillgrund´s impact on the environment Pöyry's experts worked closely with the local Swedish county administration, both during project development and construction.
When measuring the noise level during operation, it was found that the sound from the wind farm was actually lower than the background noise. “We had great difficulty to even measure it,” says Thomas Davy, Project Manager at Pöyry, who was responsible for several important environmental studies before, during and after construction.
Since Lillgrund became operational in November 2007, it has delivered renewable energy completely in line with initial estimates.
The wind farm is expected to be operational for 20-25 years. After which almost all the parts can be recycled and the site restored completely. The environmental impacts of the decommissioning of a wind farm, is approximately the same as when constructing it.
The experiences from Lillgrund have been documented carefully and publicly. The client and other project developers were able to take full advantage of the lessons learned in other wind projects. It is knowledge of great value for the further expansion of wind power; still a young industry under development.