Design Wind Power Turbine - Hybrid Anisotropic Materials for Wind Power Turbine Blades - page 15

2

Design Win d Power Turbine

2.1 Introduction

Wind.technology.is.measured.by.the.nature.of.the.resource.to.be.harvested..
The.United.States,.particularly.in.the.middle.of.the.country.from.Texas.to.North.
Dakota,.is.rich.in.wind.energy.resources,.which.is.now.measured.at.a.50-m.
elevation.. Measuring. potential. wind. energy. generation. at. a. 100-m. elevation.
(the.projected.operating.hub.height.of.the.next.generation.of.modern.turbines).
greatly.increases.the.U.S..land.area.that.could.be.used.for.wind.deployment.
Taking.these.measurements.into.account,.current.U.S..land-based.and.off-
shore.wind.resources.are.estimated.to.be.suficient.to.supply.the.electrical.
energy.needs.of.the.entire.country.several.times.over.
Wind. turbines. capture. the. wind's. energy. with. two. or. three. propeller.
blades. that. are. mounted. on. a. rotor. to. generate. electricity.. The. turbines. sit.
high.atop.towers,.taking.advantage.of.the.stronger.and.less.turbulent.wind.at.
100.ft..(30.m).or.more.above.ground..A.blade.manufactured.from.glass/iber.
epoxy.composites.acts.much.like.an.airplane.wing..When.the.wind.blows,.a.
pocket.of.low-pressure.air.forms.on.the.downwind.side.of.the.blade..The.low-
pressure.air.pocket.then.pulls.the.blade.toward.it,.causing.the.rotor.to.turn..
This.effect.is.called. lift ..The.force.of.the.lift.is.actually.much.stronger.than.
the.wind's.force.against.the.front.side.of.the.blade,.which.is.called. drag ..The.
combination.of.lift.and.drag.causes.the.rotor.to.spin.like.a.propeller,.and.the.
turning.shaft.spins.a.generator.to.produce.electricity..For.utility-scale.sources.
of.wind.energy,.a.large.number.of.turbines.are.usually.built.close.together.
to. form. a. wind. farm.. Several. electricity. providers. today. use. wind. farm. to.
supply.power.to.their.customers..New.design.and.technology.concepts.for.
increasing.the.power.of.wind.farms.have.been.proposed.and.developed.
For. example,. without. changing. the. location. of. the. rotor,. energy. capture.
can.be.increased.by.using.longer.blades.to.sweep.more.area..Blades.that.are.5.
to.16.percent.longer.can,.for.the.same.rated.power.output,.produce.a.10.to.35.
percent.increase.in.capacity.factor..Building.these.longer.blades.at.an.equal.
or.lower.cost.is.a.challenge.because.blade.weight.must.be.capped.while.tur-
bulence-driven.loads.remain.no.greater.than.what.the.smaller.rotor.can.han-
dle..With.the.potential.of.new,.structurally.eficient.airfoils,.new.materials,.

15