Author Topic: Power calculation  (Read 797 times)

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newind

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Power calculation
« on: April 07, 2009, 01:36:18 AM »
Hi,

Does this formula apply across the board? ie; typical 3 blade turbines vs vertical turbines? I got it from the AWEA site.

Thanks,

new guy.


Wind Turbine Power:


    P = 0.5 x rho x A x Cp x V3 x Ng x Nb


where:

P = power in watts (746 watts = 1 hp) (1,000 watts = 1 kilowatt)

rho = air density (about 1.225 kg/m3 at sea level, less higher up)

A = rotor swept area, exposed to the wind (m2)

Cp = Coefficient of performance (.59 {Betz limit} is the maximum thoretically possible, .35 for a good design)

V = wind speed in meters/sec (20 mph = 9 m/s)

Ng = generator efficiency (50% for car alternator, 80% or possibly more for a permanent magnet generator or grid-connected induction generator)

Nb = gearbox/bearings efficiency (depends, could be as high as 95% if good)

« Last Edit: April 07, 2009, 01:36:18 AM by (unknown) »

electronbaby

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Re: Power calculation
« Reply #1 on: April 06, 2009, 07:43:45 PM »
yes, it should work for both types. Be careful when calculating the Cp with drag based props.
« Last Edit: April 06, 2009, 07:43:45 PM by electronbaby »
Have Fun!!!  RoyR KB2UHF

newind

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Re: Power calculation
« Reply #2 on: April 07, 2009, 08:21:10 PM »
Thanks.
« Last Edit: April 07, 2009, 08:21:10 PM by newind »