Dynamic behaviour of suction caissons

Chapter 1
Introduction
Offshore wind energy is a promising source of energy in the near future, and the
plans for expanding the capacity in the European seas will increase the percentage
of total electrical consumption produced by wind power. The offshore wind power
generation by wind turbines is briefly introduced in this chapter. Subsequently, the
various foundation types for offshore wind turbines are discussed. Afterwards, the
need for further research and within foundation of offshore wind turbines and the
research aims of the project are presented. At the end of the chapter an outline of the
thesis is given.
1.1 Offshore wind turbines
Wind energy has proven to become a significant and powerful global energy resource. The
international developments in wind energy technology has been governed by the European
market for the last 25 years and the wind energy technologies have been well established
in most western European countries. In 2004 Germany achieved 7 % (16,629 MW),
Spain 6.5 % (8,263 MW), and Denmark 20 % (3,117 MW) of the total national electrical
consumption from wind energy resources, according to the Global Wind Energy Council
(www.gwec.net). The general aim of the Renewable Energy Policies for most countries
with significant wind energy potential is to increase the percentage of total electrical
consumption produced by wind power. The wind power has until recently been based on
onshore wind turbines, but the newly developed megawatt sized wind turbines and new
knowledge about offshore wind conditions are improving the economics of offshore wind
power. Hence, offshore wind energy is rapidly becoming competitive with other power
generating technologies. The continuous improvement in wind turbine technology means
that the wind turbines have increased tremendously in both size and performance during
the last 25 years. The general output of the wind turbines is improved by lager rotors
and more powerful generators. In order to reduce the costs, the overall weight of the
wind turbine components is minimized, which means that the wind turbine structures
become more flexible and thus more sensitive to dynamic excitation.
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