Transcript FLOATING WIND TURBINES

FLOATING
WIND
TURBINES
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INTRODUCTION

Renewable energy is energy which comes from natural resources such
as sunlight, wind, rain, tides, and geothermal heat, which are renewable.
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Climate change concerns, high oil prices, and increasing government
support, accelerates the growth of this sector.
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In 2008, about 19% of global final energy consumption came from
renewable sources.
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With nations pledging to reduce the carbon emission to counter global
warming, the need for systems that generate renewable energy has been
on a rise.
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WIND POWER
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Wind power is the conversion of wind energy into a useful form of energy,
such as
wind turbines to make electricity,
wind mills for mechanical power,
wind pumps for pumping water or drainage,
sails to propel ships
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Wind energy has been the world’s fastest growing source of electricity
during the past decade, with over 20% annual growth
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Energy production from wind was 340 TWh, which is about 2% of worldwide
electricity usage.
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WIND TURBINES
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A wind turbine is a rotary device that extracts energy from the wind.
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If the mechanical energy is used directly by machinery the machine is called
a windmill.
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If the mechanical energy is instead converted to electricity, the machine is
called a wind generator.
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A wind farm is a group of wind turbines in the same location used for
production of electric power.
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Wind farms and wind turbines are built onshore as well as offshore.
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FLOATING WIND TURBINES
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A floating wind turbine is an offshore wind turbine mounted on a floating
structure.
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As of December 2009, there have been two operational floating wind
turbines
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BLUE -H
80 kW
21 km off the coast in waters 113 meters deep, southeast of Italy.
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HYWIND
2.3 mW
10 km off the coast of Karmoy, Norway in 220-m deep waters.
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THE NEED
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Power Output from a wind turbine is proportional to the cube of wind velocity
and to the square of the rotor diameter.
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The wind can be stronger up to 10 m/sec and steadier over water due to the
absence of topographic features.
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Existing fixed-bottom wind turbine technology deployments had been limited to
water depths of 30-meters.
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Worldwide wind resources are abundant over deep-waters.
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Wind should be steady and consistent for the smooth working of turbines.
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Noise and visual pollution created by fixed turbines near the costal areas
are to be avoided.
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POWER CURVE
Simplified wind turbine model.
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Power [MW]
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Maximum
Power
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Constant
Power
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1
0
0
5
10
15
20
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Relative wind velocity [m/s]
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WORLDWIDE WIND SPEED DISTRIBUTION
Wind velocity increases from lighter to darker shade.
From 1m/s to 10 m/s
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DEEP WATER OFFSHORE TURBINES
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FEATURES
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Floating platforms can be classified into.
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single-turbine-floater (one wind turbine mounted on a
floating structures).
multiple turbine floater (multiple wind turbines mounted
on a floating structures)
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The electricity generated is sent to shore through undersea HVDC cables.
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There are mainly three types of systems used for station keeping for the
turbine.
Barge System ,Spar Buoy System ,Tension Leg System
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THREE MAJOR DESIGNS
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Barge Systems
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Spar Buoy
Systems
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Tension Leg
Systems
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WIND TURBINE
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MOORING
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It is the process of fixing the
floating structure to the seabed.
Absorb dynamic loads, transfer
load to seabed
TWO TYPES
Catenary
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Taut leg
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FORCES ACTING ON THE TURBINE
Hydrodynamic loads
Aerodynamic loads
• Horizontal and Vertical loads
• Dynamic and static loads
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DRIVERS
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Higher wind velocities allow higher capacity turbines to be installed.
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Thus giving much more power output per installation when compared to
fixed turbines.
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Lower Offshore Wind Turbulence – Longer Turbine Life ~ 25-30 Years
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Wind isFree
Inexhaustible
Environmentally Friendly
Clean
Safe &
Cost Effective Energy Source.
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CHALLENGES
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Huge initial cost when compared to other renewable energy sources.
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The economics of deepwater wind turbines will be determined by the costs
of the floating structure and power distribution system when compared to a
fixed turbine.
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Enough buoyancy to support the weight of the turbine and to restrain pitch,
roll and heave motions .
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Only at few sites with high wind speeds can compete economically
with conventional power production ,at present.
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CHALLENGES(contd..)
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Offshore construction is more complicated and it should survive severe
marine environments.
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Maintainace is high when compared to on-shore turbines.
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Complexity of the system.
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CONCLUSIONS
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Blue H has successfully decommissioned the unit as they are planning to
build a 38-unit deepwater wind farm at the same location.
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The US State of Maine will be soliciting proposals in September 2010 to
build the world's first floating, commercial wind farm.
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Portugal govt is partnered with Principle Power to install a multi-megawatt
full-scale floating wind turbine off the coast of Portugal in 2011.
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The enormous wind energy resource offshore, covering more than 70% of
the Earth’s surface, can be effectively tapped resulting in a cleaner and
smarter energy …
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THANK YOU!
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