Here is a web site that has lots of info about energy storage systems - it has a section on pumped storage. It also covers some large battery systems and...
Hello, Consider 2 permanent magnet motors - one rated 40 volts dc and the other rated 75 volts dc - being used as generators for small micro hydro system. Both...
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...
Dear Group, Has anyone had experience running micro hydro systems in freezing (-20C) conditions? I have a 4 inch (100mm) penstock pipe that froze solid. It's...
not enough info. Steve Spence Dir., Green Trust http://www.green-trust.org Contributing Editor http://www.off-grid.net http://www.rebelwolf.com/essn.html...
All things being equal the 40 VDC should put out more amps......but all things are rarely equal....the answer begs for more details......mark Hello, Consider 2...
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...
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...
rkweir@...
Feb 2, 2005 6:53 am
5528
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...
The business case that makes any type of energy storage work is that "off peak" power used to charge the system typically has a lower cost value than "on peak"...
I'm very new to this list but, from my experience moving water through 4 inch or even 3 inch should not freeze at that temperature. I have 1200 feet of 4 and 3...
Leigh Hauter
lh@...
Feb 2, 2005 6:57 am
5531
Hi! If both motors are able to the same outcome effect at 500 rpm, the 40 Volt motor has to deliever more ampers. Appr. multiplicated with the factor 1,88...
The kinetic energy in the first case is converted to heat by friction. It may not be noticed because it takes a considerable amount of energy to heat water. ...
With a PMG voltage is proportional to rpm. The ability to delivery current depends on such things as wire size, saturation of core etc. Voltage depends on the...
Chis, The current is related to the wire size, and the voltage to the number of wire turns. The power is related to the weight, so weigh them, and the heaviest...
That's the answer I was looking for - thanks. ... From: H2MJD <h2mjd@...> To: <microhydro@yahoogroups.com> Sent: Tuesday, February 01, 2005 12:17 PM ...
Dominic: The energy from the "turbine" comes from the potencial energy in the upper tank just to the time that tank is empty. Afterwards, nothing to do: the ...
Dear Chris: As penstock is of relative low diameter (4") and some long, at -20 șC must freeze if the water velocity is low and as you can see. I think that...
Yes, I know Reinhold also. The problem seems to be in the practical application of the heat generator. The machine is for generating hot air is a "bad...
... This can be a trick question, however I don't think it is intended this way. As others have already noted more information is required. Let's look at what...
Max Enfield
max@...
Feb 2, 2005 7:02 am
5540
... Yes the difference in potential energy is the same. In the first case where the water flows unimpeded down the pipe most of the potential energy is lost as...
Max Enfield
max@...
Feb 2, 2005 7:03 am
5541
Hi Chris, As for pipe freeze, there is a good chance that the problem is caused by frazil ice. Frazil ice forms in "supercooled" water, or open water with no...
bby2001@...
Feb 2, 2005 7:39 am
5542
Carlos! Thanks for the come-back. Even after all this time I have not been able to locate anybody who has given as much thought as he to the heating of air by...
Work is power times time, so the symbol is kWh, sometimes seen as kW-h. It's multiplication, not division as implied by "/". Frank Leslie ... From: friend...
Hi, Some years ago I have been using a propellor current-meter. I can find out about the brand, if you wish. If you have one, you also can hold a GPS in the...
Chris, The 40 volt motor may produce more Amperes, but this is highly misleading. Total power produced is the main goal, and Power = Amperes X Volts, so now, ...
Note that the first item in the list provided by google (which I heard on the radio this morning is up $20/share), is part of an online reference that has been...
Thanks Max, A nice clear explanation. So - on the water getting warm thing... Lets say we have 1 litre of water in a tank 10 meters above the second tank. I...
Max, et al., Is "two thirds limit to the power " related to the Betz Limit of 59.3% of available power in the wind power domain? Frank Leslie ... From: Max...
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