Author Topic: hydro interest in friends 20 acre lake  (Read 996 times)

0 Members and 1 Guest are viewing this topic.

gcsmith

  • Newbie
  • *
  • Posts: 2
hydro interest in friends 20 acre lake
« on: March 13, 2007, 02:30:01 AM »
 I'm an electrical contractor in northern n.j. I've only looked at the site 2x.I need to do the flow and head calcs I an aware.the site is an earth dam ,aprox 20 acre lake.the spillway is a concrete vault  aprox 6 foot sq ,aprox 6ft off the face of the dam,which allows the water to run throuh and under the dam in a 6ft sq tunnel that I can walk threw.Seems to be a great potential.inthe summer the flow is little 100 gallons a min,winter and spring 1000 gal a min. I just got 2 3phase 120 volt  induction motors very old but working when they were removed,does it sound as if there is any potential to use these generators here guesstimate head to be 15 to 20 feet.these 2 motors are directly connected to  a cetrificul pump,this was my idea to run the water through these pumps backwards to turn the motor generator to produce heat for as many greenhouses as possible to grow flowers.I'm a newbie and will try to send pictures next posting if I get some feed back

                          thanks GCSMITH
« Last Edit: March 13, 2007, 02:30:01 AM by (unknown) »

gcsmith

  • Newbie
  • *
  • Posts: 2
Re: hydro interest in friends 20 acre lake
« Reply #1 on: March 13, 2007, 03:51:58 AM »
oh,I forgot to mention that the pump housing  inlets "in reverse "are 6 inch.I've

 never explored anything like this before,it seems fascinating,I want to develope ever site in n.j.I have noticed lots of old dams as I look around,should really help to have the contractor license here,guess all I need now is MONEY

                   greg-GCSMITH
« Last Edit: March 13, 2007, 03:51:58 AM by gcsmith »

Nando

  • Hero Member
  • *****
  • Posts: 1058
Re: hydro interest in friends 20 acre lake
« Reply #2 on: March 13, 2007, 04:55:28 AM »
GC:


The use of a Pump as a Turbine (PAT) in your site is not possible, one of the problems is the head available in your site.


Using your basic GUESSED values :

100 gallon/minute = 6.3 liter/second

head 15 feet = 4.5 meters


The power available is 6.3 * 4.5 * 9.81 = 278 watts, then one needs to apply the efficiencies for each part of the system and for these small power levels the power available would be around 140 watts if carefully done for 3.36 KWH/day of useful harvested energy.


In winter if the water volume is real the energy available would be then about 1.4 KW for 33.6 KWH/day useful, indeed, if a careful analysis of the site and the installation of a well built hydro turbine system.


First step and accurate site evaluation without any GUESSES since water is a very deceiving "animal" that is constantly erroneously "GUESSTIMATED"


Nando

« Last Edit: March 13, 2007, 04:55:28 AM by Nando »

Flux

  • Super Hero Member Plus
  • *******
  • Posts: 6275
Re: hydro interest in friends 20 acre lake
« Reply #3 on: March 13, 2007, 07:22:25 AM »
I agree with Nando, pumps are not effective as turbines at low head. They are also not suitable for large variations in flow even at high head.


You are not going to get much useful heat in summer, if your figures are reasonable you may be ok in the winter with a suitable low head turbine.


Flux

« Last Edit: March 13, 2007, 07:22:25 AM by Flux »