# How to calculate the turbine output at hub height????

• Hamza Ali
• Topic Author
27 Sep 2022 08:48 #11492 by Hamza Ali
Hello Sir / everyone.

I want to ask how to calculate the turbine output at hub height wind speed?

I can see formula/equation 25, 26, 27 and 28 (page17-18) in MANUAL. but i am unable to appropriately use the values and that is
why my calculations by hand are wrong. can u pls solve it?

(screenshots and EXCEL FILE and screenshots are attached.)

guide me please, what does it mean by V1,V2 and P(V) (although i can read the description but i am unable to use the correct values and get the right result)

can u please solve any example? (take any wind turbine power curve in order to solve).

Thanks.
##### Attachments:

• Paul Gilman
27 Sep 2022 23:08 - 28 Sep 2022 17:35 #11499 by Paul Gilman
Hi Hamza Ali,

V1 and V2 are wind speed values from the wind resource data file. This assumes that the file contains wind speed data at two or more hub heights.

For example, if the turbine height is 110 m, and the file contains wind speed columns for 100 m and 125 m, then V1 = wind speed at 100 m and V2 = wind speed at 125 m. P(V1) is the power in kW from the power curve at V1, and P(V2) is the power in kW from the power curve at V2.

Best regards,
Paul.
Last edit: 28 Sep 2022 17:35 by Paul Gilman.

• Hamza Ali
• Topic Author
28 Sep 2022 10:03 - 28 Sep 2022 17:33 #11500 by Hamza Ali
Sir honestly I did not get you. I am confused, doing the reverse math since yesterday and didn't get the right of these three equations. I need ur help in detail.

Can u pls do the manual (handwritten calculations for 2-3 steps pls)? I have attached an excel sheet, screenshots and manual to see the formula! pls favour me and do the hand calculation and let me understand pls.

How P(V1) is the power (in kW) from the power-curve at 100m? (at 100m, really? we know that cut-off speed is 25m/sec)! weather file (with name SAME) is attached.

#### File Attachment:

File Name: SAME.csv
File Size:931 KB

SAM result excel sheet is also attached. and in this excel sheet, my calculations are also there. please show me how to use values and equations. Its a request sir pls.

The most important question is (to be specific) = in manual, it is written as: "see the screenshot in this msg".  how to find rho j and rho o?

﻿Sir, I request you to pls find the final answer of eq. 26, 27 and 28! PLEASE.

#### File Attachment:

File Name: SAME.csv
File Size:931 KB

reply as soon as possible. (or can we talk on a phone call, sir?

Thank you so much.
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Last edit: 28 Sep 2022 17:33 by Paul Gilman.

• Paul Gilman
28 Sep 2022 17:38 #11509 by Paul Gilman
Hi Hamza Ali,

Please see my revised response above.

Best regards,
Paul.

• Hamza Ali
• Topic Author
02 Nov 2022 07:03 - 02 Nov 2022 23:37 #11632 by Hamza Ali
Respected Sir,

can u please clear my this confusion (below explained): Query referring to the previous conversion on this topic (confusion is not clear)

Turbine hub height is 93m.

say for example for any hour j,  I have four height and their wind speeds.

50m = 6m/s
80m = 7m/s
90m = 8m/s
100m = 100m/s

as the Turbine hub height is 93m.

Note: in SAM manual statement is written like this: "V1 and V2 = the next smallest and largest power curve wind speed to the hub height wind speed, respectively."

Q1 = now according to above SAM manual statement and as per given my heights and their wind speeds, what is the V1 and V2 value?
Q2 = and what is the value of P(V1) and P(V2) ?????

Note: in SAM manual statement is written like this: "P(V1) and P(V2) = the turbine output at wind speed V from the power curve"

Power curve for Gamesa G114 - 2MW is =

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Last edit: 02 Nov 2022 23:37 by Paul Gilman.

• Paul Gilman
02 Nov 2022 23:41 #11638 by Paul Gilman
Hi Hamza Ali,

In this case:

V1 = 9 m/s
V2 = 10 m/s (I think you typed a mistake. I assume you mean 10 m/s, not 100 m/s)

P1 = 1836 kW
P2 = 1965 kW

Best regards,
Paul.