HI Chris Hopkins
Nice to hear from another micro hydro user so close
by. I operate a small battery charging system in West
Chazy, NY(near plattsburgh, NY). My 2 inch plastic
pipe runs 1400 feet with 185 feet of drop and normally
run it at 15 gal./min.(1/4 inch nossel). My pipe is
buried the entire distance but the rocky terrain only
allowed me to cover it 6 inches on much of the steeper
drops. I have run it for 10 years now and have only
had problems with freezing twice. If we have at least
6 inches of snow no amount of cold weather can cause
problems. If we have little snow and a week of
sub-zero temperatures I have experienced a gradual
drop in flow and output from my turbine. If I don't go
up the hill and shut the intake valve the pipe will
become blocked with ice which could put me out for the
rest of the winter. The problem I have is that under
low snow conditions and extremely cold temperatures
the small stream that I draw from can actually start
to freeze solid. As the flow is reduced to a trickle
it starts to freeze in my pipe where it passes through
my 18 inch high dam. I also used a small section of
metal pipe where it passes through the dam and this
may contribute to the problem. Our systems are quite
different; you obviously have more flow which should
work to your advantage. Does your freeze ups come
under low snow conditions? Is the flow in your stream
seriously affected by such conditions? Not sure if
this is any help- Let me know.
Peter Allen
West Chazy, NY
--- [email protected] wrote:
>
> ------------------------ Yahoo! Groups Sponsor
> --------------------~-->
> Has someone you know been affected by illness or
> disease?
> Network for Good is THE place to support health
> awareness efforts!
>
http://us.click.yahoo.com/RzSHvD/UOnJAA/79vVAA/FGYolB/TM
>
--------------------------------------------------------------------~->
>
>
> There are 25 messages in this issue.
>
> Topics in this digest:
>
> 1. Re: Confused about potential energy.
> From: "H2MJD" <[EMAIL PROTECTED]>
> 2. Re: Freezing penstock
> From: [EMAIL PROTECTED]
> 3. Re: Confused about potential energy.
> From: "friend" <[EMAIL PROTECTED]>
> 4. RE: Confused about potential energy.
> From: "Bill Shanner"
> <[EMAIL PROTECTED]>
> 5. Re: Freezing penstock
> From: Leigh Hauter <[EMAIL PROTECTED]>
> 6. Re: Permanent magnet motors
> From: "friend" <[EMAIL PROTECTED]>
> 7. Re: Confused about potential energy.
> From: "Steven Schoeffler"
> <[EMAIL PROTECTED]>
> 8. Re: Permanent magnet motors
> From: Michael Lawley
> <[EMAIL PROTECTED]>
> 9. RE: Permanent magnet motors
> From: "Frank Leslie" <[EMAIL PROTECTED]>
> 10. Re: Permanent magnet motors
> From: "Hoppy" <[EMAIL PROTECTED]>
> 11. Re: Confused about potential energy.
> From: Carlos Bonifetti
> <[EMAIL PROTECTED]>
> 12. Re: Freezing penstock
> From: Carlos Bonifetti
> <[EMAIL PROTECTED]>
> 13. Re: Re: Heat Generator
> From: Carlos Bonifetti
> <[EMAIL PROTECTED]>
> 14. Re: Permanent magnet motors
> From: Max Enfield
> <[EMAIL PROTECTED]>
> 15. Re: Confused about potential energy.
> From: Max Enfield
> <[EMAIL PROTECTED]>
> 16. Re: Freezing penstock
> From: [EMAIL PROTECTED]
> 17. Re: Heat Generator
> From: "georgewrbaldwin"
> <[EMAIL PROTECTED]>
> 18. RE: Confused about potential energy.
> From: "Frank Leslie" <[EMAIL PROTECTED]>
> 19. Re: Measuring stream flow
> From: Jacques de M�vius
> <[EMAIL PROTECTED]>
> 20. Re: Permanent magnet motors
> From: [EMAIL PROTECTED]
> 21. Re: Measuring stream flow --- How? see
> Google for almost everything!
> From: "Joseph Hartvigsen"
> <[EMAIL PROTECTED]>
> 22. Re: Confused about potential energy.
> From: "ReadFamily" <[EMAIL PROTECTED]>
> 23. Heat Generator
> From: "Steven Schoeffler"
> <[EMAIL PROTECTED]>
> 24. RE: Confused about potential energy.
> From: "Frank Leslie" <[EMAIL PROTECTED]>
> 25. Re: Heat Generator
> From: "georgewrbaldwin"
> <[EMAIL PROTECTED]>
>
>
>
________________________________________________________________________
>
________________________________________________________________________
>
> Message: 1
> Date: Tue, 1 Feb 2005 12:27:34 -0500
> From: "H2MJD" <[EMAIL PROTECTED]>
> Subject: Re: Confused about potential energy.
>
>
> Where did the energy that was extracted from the
> system by the turbine come from?
>
> The Sun.......then rain
>
>
> I'm sure that the answer is somewhere in the
> statement in the first case where the water flows
> through a simple pipe. The potential energy in the
> system has changed - so where did the energy go? I
> dont know.
>
> it returned to its lowest form of
> entrophy.......heat
>
> [Non-text portions of this message have been
> removed]
>
>
>
>
>
>
>
________________________________________________________________________
>
________________________________________________________________________
>
> Message: 2
> Date: Tue, 1 Feb 2005 12:41:30 EST
> From: [EMAIL PROTECTED]
> Subject: Re: Freezing penstock
>
>
> Chris,
>
> I have had a 72 inch pipe freeze so the problem is
> not unique. Insulation is
> a good way to proceed. You might try slipping a
> larger diameter plastic pipe
> over the smaller one so you have a dead air space.
> Then seal the ends so the
> cold air won't move up and down the pipe. Then paint
> the pipe black so
> sunlight will help. Alt.2 build a box around the
> pipe fill it with dry leaves. Alt
> 3 shovel snow onto the pipe so that the snow will
> help insulate it. Alt 4
> Move to Florida.
>
> Bob
> Robert K. Weir
> Hydroscreen CO. LLC
> _www.hydroscreen.com_ (http://www.hydroscreen.com)
>
>
> [Non-text portions of this message have been
> removed]
>
>
>
>
>
>
>
________________________________________________________________________
>
________________________________________________________________________
>
> Message: 3
> Date: Tue, 1 Feb 2005 18:42:04 +0100
> From: "friend" <[EMAIL PROTECTED]>
> Subject: Re: Confused about potential energy.
>
>
> Hi. You mixed up potential energy (kW) with done
> work (kW/h), the waterflow from level 1 to level
> ziro is much faster without the turbin.. so you
> changed waterflow speed into done work.
> With regards
> Friend_m
> ----- Original Message -----
> From: ReadFamily
> To: [email protected]
> Sent: Tuesday, February 01, 2005 2:44 PM
> Subject: [microhydro] Confused about potential
> energy.
>
>
>
>
>
> I was thinking about the pumped water storage idea
> and then started to think about the energy in the
> system.
>
> If there is a full tank at the top and an empty
> tank at the bottom then the potential energy in the
> system is mgh (mass of water x gravitational
> constant x height difference).
>
> So if you let the water flow from top tank to
> bottom tank through a simple pipe then the potential
> energy is gone. (assuming bottom tank is at height
> 0).
>
> Now put the water back into the top tank and this
> time put a turbine in the pipe. The water flows from
> the top tank to the bottom tank and power is
> generated by the turbine and extracted from the
> system. But the difference in potential energy in
> the system is the same. All the water from the top
> is now in the bottom. Where did the energy that was
> extracted from the system by the turbine come from?
>
>
=== message truncated ===
------------------------ Yahoo! Groups Sponsor --------------------~-->
What would our lives be like without music, dance, and theater?
Donate or volunteer in the arts today at Network for Good!
http://us.click.yahoo.com/TzSHvD/SOnJAA/79vVAA/FGYolB/TM
--------------------------------------------------------------------~->
Does your company feature in the microhydro business directory at
http://microhydropower.net/directory ? If not, please register free of charge
and be exposed to the microhydro community world wide!
NOTE: The advertisements in this email are added by Yahoogroups who provides us
with free email group services. The microhydro-group does not endorse products
or support the advertisements in any way.
More information on micro hydropower at http://microhydropower.net
To unsubscribe: send empty message to [EMAIL PROTECTED]
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/microhydro/
<*> To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
