Hydropower specs

[Phantasm]

Oh .....I hate my screen name.... I thought I was messing around with a broken web site cause I must have tried over 50 screen names and nothing went through........Oh well...... the damage is done! You will rarely see me.

Anyway here's my question



The City of Columbus operates O'Shaughnessy Dam, a low-impact hydropower installation on the Scioto River, at a head of 5.5 meters. The installation consists of two turbines spinning at 64.3 rpm.  Each turbine has an output capacity of 25.9 megawatts.  Photo below from the 2003 Central Ohio Solar Tour as participants view base of O'Shaughnessy Dam near turbine room.

This is an excerpt from this web site

http://www.greenenergyohio.org/page.cfm?pageId=54

With the 5.5 meters of head could someone give me a high end ball park figure of the gpm's to turn the turbines at the 64.3 rpm. Or what I'm mainly looking for is a head pressure and volume of water to power up a typical megawatt generator. And I'll guess there is no such thing as typical for each one is probably custom designed.

Earl

 

[Phantasm]

I apologise for that Photo advertisement. I did not do that. It must have been a part of the website excerpt. I was never into advertising and will never be. I have got too many things to design!

 

[rmw]

What is wrong with using the formulae in bullet point #4 in the link given?

rmw

And PS; I think your handle rocks.

 

[Phantasm]

Thank you rmw
Absolutely nothing is wrong with bullet no 4 and It didn't even register when I seen it earlier. Time for me to take a break.

And thanks for the compliment about my handle!

Earl

 

[itsmoked]

Let me toss in a wrench.

I once owned property in WA with the intent of hydropower production. The flaming hoops you need to jump thru to even be allowed to contemplate dropping anything of any type permanently into a river, creek, stream, or drainage ditch these days are mind boggling. You will likely never get permission these days.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[wolf39]

The picture shows a dam with a head considerably higher than 5.5 meters. However, with a head of 5.5 meters and a turbine output of 25.9 MW the required flow is about 560 cubicmeters per second under the assumption that the penstock efficiency is 95 percent and the turbine efficiency is 90 percent.

The formula given under 4. may be valid for micro hydropower with their low efficiency components. A turbine of 25.9 MW does not fall under such category. By the way: The flow dimension has to be cubicfeet per second (feet power three per second).

Best regards

Wolf

 

[Phantasm]

Thank you itsmoked
I have no intention of actually doing this. I was curious about math and the specifications.

And thank you wolf39
You provided me with the information I needed. That formula in bullet 4 had me wondering. I was looking for a fluid volume flow rate in cubic format and if there is a math formula where one can convert a flow rate into a volume flow rate I don't know what it is or where to look.

It's not here

http://www.engineeringtoolbox.com/unit-converter-d_185.html#Volume_flow

P.s I deeply regret the timing of me looking for answers to this question. In no way does this have anything to do with the tragic flooding problems anyone is facing. This has everything to do with a project I started years ago and progress is at a snails pace.

 

[wolf39]

Considering an efficiency of 100% each for the penstock, the turbine and the generator, the formula for calculating a generator output is as follows:

P = 9.81 * H * Q

P (electrical output) in kW
H (head) in meters
Q (flow) in cubicmeters per second

So, for a 1 Megawatt generator the product of head and flow is about 102, under the assumption of a total efficiency of 100% for the conversion from mechanical power to electrical power. In practice you can use a factor of about 8.8 (instead of 9.81) in the above formula for a modern hydro generator output, this considering all component efficiencies mentioned above. However, for micro power generators the factor is well below the above 8.8 figure

Regards

Wolf

http://

http://WWW.HYDROPOWER-CONSULT.COM

 

[itsmoked]

wolf39; Please note that you are NOT to include email addresses in your posts. If you will notice your first post had it removed.


Keith Cress
kcress -

http://www.flaminsystems.com

 

[itsmoked]

BTWay Hello wolf39 and welcome to Eng-Tips. Thanks for the contributions.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[wolf39]

Sorry, Keith.

This was a misunderstanding! I thought that under step 3 my email address was required.

Regards

Wolf

 

[wolf39]

The O'Shaughnessy Dam has two hydro units installed according to the information I found. Unit 1 has an output of 1.4 MW and unit 2 an output of 4.0 MW. Both units are operational since 1988.

Wikipedia is mentioning a head of 18 feet (5.5 meters) but from the photograph shown I think that the head in reality is about 18 meters, not 18 feet. Does the photograph really depict the O'Shaughnessy Dam?

Best regards

Wolf

http://www.hydropower-consult.com