Water Lift

The idae is sound insofar as you can store energy as a head of water, but obviously it takes slightly more energy to raise the water than you will recover from it (losses in friction, efficiency, heat etc)

The one fundamental mistake is your comment ..

2.) the weight of water naturally exceeds the weight of the air.

This is completely wrong.. Atmospheric pressure is exactly what it's name suggests...and is the weight of the air...and that corresponds to exactly how much force you can generate with a vacuum.

A 'vacuum' doesn't actually apply any force...it is the atpmospheric pressure which applies the force...thus you can only ever suck a column of water up to 33feet (approx)

I hope this clarifies the situation. (Don't feel bad...many people make this error!)

Del

Is this my error?
"the weight of water naturally exceeds the weight of the air."

In the container there is a fixed amount (volume) of air, which is
pressurised, by the external air, pressing down on the water, which
in turn, pressurises the air in the container.

Correct me if I am wrong, but this volume of trapped air, seems to
have a "negligible" weight? compared to the identical volume of water
replacing the air. That is, for a little energy to remove the trapped air;
nature, by air pressure, refills the space with much heavier water.

This water has more weight (i.e. energy) than the previous air.
It seems we can encourage nature to provide us with an advantage?

Or am I seeing this wrong? If we remove x cubic metres of air and then
nature replaces it with x cubic metres of water, have we "won" energy?
(ignore all frictional pipe losses etc.)

jt.

Try getting a 3' vertical length of clear hose and sucking out the 'negligble weight' of air to allow the water to flow in.

You will soon see it is not negigible, as you are working against atmospheric pressure. I'll bet you can't suck the water column up even a metre.

I can't think of a better way to explain it...

Imagine a tall container approx. 30 ft high with the base
connected to a water supply, eg.. a pond or lake.
The inlet/outlet pipe to the tank, has an electrical generator
included. A pipe connected at the top of the tank creates a
partial vacuum within and the water rises inside the tank, due
to air pressure; the tank fills up to approx. 30 ft in height.

27" w.c/2ft-3" = 1 psi . What do you actually want to do? Generate electricity with water pressure of 30 psi? Is the water going to drive the blades of the electric generator ? What output W/Kw capacity of generator you have in mind? What Gpm flow it requires/w or Kw? Are you aware of the quantity of water flow Gpm Vs W or Kw? Prior going further you need to detail:

Electric Generator type/capacity/in take Gpm?

Total Storage Volume & Container size?

Water passing via the generator after drive returning back?

Generating electricity with water from a 30 ft container is more complex than what you think is my honest opinion.

The sizes (numbers) are not relevant; we can make them as
big or as small as we like; we just need to know if it will work,
and if so, the best criteria.

We could use a 6 foot wide tank or a 36 foot wide tank a 1 kw
generator or a 1 meg. watt generator, it's the calculations of
the principle I seek.

When the air pressure (in the tank) is reduced the water rises
and replaces the removed volume of air. The water is heavier;
will this provide an advantage? What are the principle calculations?

It "seems" to work well on a small scale, I would just like to actually
confirm it with the maths before tackling it in a big way.

jt.

Since you've made the small scale and it "seem" to work why the fuss! magnify it as per your requirement.Good luck.

"The sizes (numbers) are not relevant; we can make them as big or as small as we like; we just need to know if it will work, and if so, the best criteria."

NOT SO! The size of the tank is quite relevant. The size of the tank is quite relevant as that determine the quantity of water it 'can' hold which in turn determines the size of the turbine and generator.

You mention a vacuum valve which will (Hopefully) pull water to the 30 ft height of the tank, which it cannot do! At -14.7psi (O psia) the water would have been boiling due to the low pressure per the thermondynamic properties of water. It would take all of the power generated to run the vacuum pump and that would rule out the whole project. An intermittent system such as this is useless unless you intended to use a bank of storage batteries. There is still the negative energy balance working against you any way you slice it.

Consider using an an air lift? but here again the power consumption of the air compressor will exceed the power output of the generator.

Drop the whole idea, have a hot cup of java, and a cookie or two, read a good book and relax. You might be inspired to come up with something workable.

U said it Stan

Sorry when I posted this I forgot to log in:

Since you've made the small scale and it "seem" to work why the fuss! magnify it as per your requirement.Good luck.

I've reserved a seat with others and woul'd like to see it work.

My best advice - drop the idea.

Ah, another trip down the river of denial. I just have to post to see where this goes. It's like a train wreck, you just can't not watch.

Save me a seat too.

Energy can only be converted.

Energy required for pumping out air from container from atm pressure to vacuum =

energy required to lift water.With all most ideal conditions you can generate power from water column = power you have used for creating vacuum.

The calculations requested may not be as simple as imagined. You have to consider that air is soluble in water. Simply stated, it is that the amount of air that can dissolve in water decrease with temperature and increase with pressure. Also you have to consider the surface area of the water that is exposed to air, the bigger the area of the tank or whatever vessel is assumed, the bigger will be the amount of air that will dissolve.

Oh dear, I believe this is "The Engineer's Place for News and Discussion" but i'm sorry jt take it from an actual Engineer - This will not work!!

Vacuum pumps for very high vacuum levels run at very low flow rates and would need to run for hours/days to achieve even half of the 30 feet you require. The heat losses in the motor would be colossal over such a length of time.

The length of time over which energy can be generated would be a small fraction of the time to raise the water level.

Why don't you set the tank 30 feet below the level of the lake/reservoir so it fills with water then allow the water to flow out to a lower point? Oh no wait, that's hydroelectricity! This is far better as nature does all the hard work!

If you step away from the vacuum business for a minute, what you are proposing is very much like what they do at hydroelectric dams.

Surplus off-peak power, from a source that produces continuously 24/7 (such as nuclear), is used to pump water from below the dam back up to the head pond. It can then be used to generate power during peak load periods.

A similar approach could be used to "level out" a power supply system, taking a fluctuating power source and storing part of it as water pumped into an elevated reservoir, to be "tapped" (pun intended) as required.

One twist would be if the reservoir was an enclosed pressure vessel, and the air at the top could be pressurized as water is pumped in.

That way, your power generating capacity would not be limited by volume and column height. In any case, the higher the placement of the reservoir the better (top of the hill, tower, etc.).

Bottom line, water + gravity = good, clean, reliable power.

If you can get enough water to a place where gravity can do its thing, using a clean power source, you have a clean, continuous and/or on-demand power system...

... with no batteries required.

Thank you all; for the constructive, (Munky) and the comic-sarcastic
(several others) I accept all the slings and arrows. (par for the course.)
One cannot talk about "stupid" ideas without at least some derision.

May I say, please accept not all entrants are blind to the constraints.
I accept unity, etc. and the wisdom of others; and only seek a new
method to overcome this energy problem; possibly a new application
of something "old." or well known. Ideas can originate anywhere.

It's unlikely I admit; but belief is the starting point and, if one doesn't
originate and experiment, we are just robots on a daily conveyor belt.

One day! eureka! Diligence and perseverance may, just may, obtain a
reward (for my ideas) from others. If only; why didn't I think of that?
Seek and you shall find. Which reminds me of:

A lad was searching under a lamp post, and I enquired why? He said
he'd lost a pound coin, in a nearby alley. So? "Why are you looking here?"
I asked? "Because there's more light here," he replied.

Thank you all for your input.

jt.

http://www.mfnb.at - a free web page in 30 secs.

The added dificulty is that the air you want to pump will inflate 10:1 under vacuum. Each liter of water you wish to "suck" becomes 10 liters at 30', 3 liters @ 20', and the back pressure of the air pump is growing just as rapidly.

Rich

Thanks for your good natured reply. Some of the flack is accumulative and most of the time the proponents of an unworkable idea are themselves the least open minded and as such tend not to be tolerated gladly. Some responses are really more a response to other posters as a result.

When we are able to benefit from the knowledge and experience of others and realize we all suffer from occasional mistaken assumptions there is progress and hope. Keep trying, maybe you'll be the one to stumble onto something yet undiscovered.

My mind has been opened and I have seen the answer.

All we have to do is take the output of the vacuum pumps that are creating over unity energy from air pressure and use it to compress air to run compressed air cars.

Oh wait, it gets better. Now we take the air cars and we hook them up to a very large horizontal mill type wheel like they used to drive with oxen to grind grain. The wheel has to be really big so we can get more mechanical advantage and more power out of the electric generator that we attach to the wheel.

Now I realize that as ground breaking and optimistic as this may seem and we are already getting at least 2X over unity let's not waste all this electricity on common applications, no. This is where my true genius shines in this next step.

We take all this free electricity see and we use it to make big magnets that we put into over-unity converters. All earths energy problems are solved.

Next problem to solve is how to keep the planet from bursting into flames because I guarantee you if this machine is ever turned on that, with no reason not to use as much power as you want, at thermodynamic crisis of untold proportion would result.

But wait, I feel a solution coming on. We could put big circulated water radiators in space with hoses and pumps to move the heat to where it can be radiated and escape. Now we can all rest easy. We are saved.

Oh I almost forgot. I'm sure that investors will be eager to get in on this opportunity so if you a couple of million lying around and want to get rich quick just send me a note and I'll get you a routing number for the deposit.

LOL

Slow down...I can't design it that quick...I'm struggling with the big mill wheel....

Hey we could use the engery to power big thrusters so we could manouver the Earth to a different location in the solar system!... Or tilt it on it's axis so that only the 'good' countries get a nice climate...(I'm sure G W B has a list...) Oh no..I've slipped int politics....

Absolutely genius! With your political aspirations and my design we can rule the world![p/]

I really like the idea of moving the planet around. That's really thinking outside the box![/p]

They can't call us negative and closed-minded now. We have pierced the envelope!

LMAO ...

Gosh, then we could use that spare power wired up to our electromagnetic traction tractor to move the earth. Then we could put some rotating coils near it to generate even more energy. And just leave an open=topped pipe about 200 miles up for our vacuum source to fill our tower.

Then build 2 towers, connected at the top. When one drains, it will suck the water up the other.

I'll watch and I will try and stay quiet too.....

Why not use the "wind" to pump water directly? People have been doing this for years.

Power companies have also been using water to drive turbine generators for years also. As long as it rains, there's water to drive generators. They charge money for producing power, 'cause to do so ain't free.

Why don't you try using a hydraulic water ram pump to fill the tank. The power from a six foot drop in water pressure (head) can be used to pump free water up as high as 100 feet. This pressure can be harnessed from streams or tidal flow. Then you are not requiring any artificial generated power to fill the tank.

These pumps seem like the material of folk lore or mystical "grandpa did it" power, but I have seen one work, and it is really amazing. You can build one for next to nothing with pvc tubing and a diaphram valve.

if you were to plug in the vacuum pump and measure how much electricity it uses then attach the generator to the water tower and release the water and measure the energy made, you will find that the energy used to run the vacuum pump exceeds what was produced by the generator. Basically, no matter how carefully you manage the presses of loading your tank you will always use more energy then you can gain.