Any such thing as "small steam turbine"?

Patrick32

I'm doing a project for a high school science fair and it involves a steam-driven turbine power plant. I would like to build two models: one demonstrating the workings of a normal power plant and another which will not release steam but will condense it and reuse it (don't ask how, it's a secret), therefore being better for the environment in three ways:
1. It will not waste water.
2: Water vapor is a greenhouse gas, so this will slow down global warming, if only very slightly.
3: The steam that is released in a normal plant must cool from well over 100 degrees Celsius to the temperature of the surrounding air, thereby warming the atmosphere. If the steam is not released, it will only have to cool to just below 100 to condense, therfore releasing less heat and, again, slightly slowing down global warming.

Anyway, I'm not very experienced with building power plants, and I could use some advice, so if you have any ideas, such as what materials I should use or where I could get them, I would appreciate your help.

randy 123

a large scale power plant has blade turbines they are hard to make without a cnc. but the tulsa can be bilt of large washers you can find at the hardware store and a bolt or thredid rod. her is a link to give you a idea of what it is http://en.wikipedia.org/wiki/Tesla_turbine
or you can look at the book
The Tesla Disc Turbine ISBN 0-9536523-2-7
your in for a big project good luck

chayced

Another good off the shelf turbine is a auto turbocharger. The problem is it won't like wet steam and it requires reduction gear to get power out.

I begin to wonder what kids are being taught in school these days. Water Vapor is a greenhouse gas? Sure, but if you honestly think man has ANY control over the amount of water vapor in the air you are sadly mistake. It's not like we evaporate it and it stays up in the sky.

Steam is not released in a normal power plant. The water is condensed and reused. The only exception to this is cooling towers seen on some power plants. These are not releasing steam but rather running cool water over a heat exchanger that then evaporates. It's rather usefull when no natural heat sink such as a river or lake exists.

Patrick32

Yeah, I know the whole greenhouse gas thing really isn't going to make a difference, but I want people to think it will

lelandmonroe

We live in Alaska - obviously solar doesn't work 6 months out of the year. We need to find a small steam generator system that can be hooked to a wood burning boiler system. Anyone have any ideas as to where to find one?

Leejjay

does anyone know a small steam turbine exists that will run off of a multi fuel stove to produce electricity?

Dogma72

I read the white papers on this site - specifically referencing the steam usage calculator program. I noted that the enthalpy of the exhaust steam was really high. I don't believe that a condensor was incorporated in this design. A question for the author - since you were not using a condensor, did you consider using the exhaust steam to pre-heat your incoming feedwater? certainly that would have markedly increased your efficiency?

Dogma72

@Patrick - Steam - from the process - from a commercial power plant is not released to the atmosphere. It goes into a condenser and the heat is rejected to a cooling fluid - usually from a nearby river or lake.

So, in total - the amount of heat that you reject to the atmosphere from a power plant is directly related to the thermal efficiency of the power plant. That said, commercial plants use the minimal amount of cooling possible because a large component of a power plants efficiency is driven by how much they have to reheat the incoming feed water - generally speaking - they want it as close to boiling as possible.

Dogma72

@Patrick why would you 'but I want people to think it will" - why would you want people to think or put emphasis on something that isn't factual? We have enough problems with ignorance in society as it is. What you are saying is just contributing to fear mongering that is already overwhelmingly part of today's society.

DoggerDan

It will run poorly. You're better off with a piston-based steam engine for the smaller stuff.

kend

Interesting ideas. My little company recently patented (U.S. #7824149) a robust, low cost, turbine which we are trying to adapt to small scale solar electric systems. We are building a few 4 to 16 inch test turbines for this purpose which will generate power in the 3- 10 KW range. If anyone is interested testing their steam producing system with this turbine please let me know and we can discuss. barlazysm@gmail.com

boab

Patrick32
There is a book called "Model Steam Turbines-How to Design and Build Them", written by Harrison. It is a 126 page book written about a 100 years ago, and is "very well done". It contains all the formulas needed to design a turbine of just about any size, and some plans for several model turbine designs. It is listed on SCRIBD, catalog# 73878136 under the above title.
That said.........these turbines in the book "aren't easy to make". Also......at the speeds they get up to, 30 to 70,000 rpm, throwing a turbine bucket would be like a .22 cal bullet, and seldom does just one bucket come off. So BEWARE. And I mean that for real.
I'd suggest for simplicity that you go the steam piston engine route in your project. There are quite a few steam engine kits available, and require a lot less steam than a turbine does. I think you'd prove your science project equally well using one piston engine and valving it from exhausting between the atmosphere, and valved to a condenser, or your secret device. Just a thought.

Guys.........by water vapor being a green house gas, I think Patrick was referring to the latent heat retained in the vapor, not it being a chemically active type of gas.
And I think Patrick's comment that he wants people to think his idea will work, is not to pull the wool over people's eyes, but to encourage them to accept it and try the idea if it works out.

boab