Thinking out of the box, way out!

[Roy Lent]

We tend to work with well known mechanisms like solar panels, wind generators, biodigesters or hydro-plants. But there are many more ideas out there, some not too well known. So here I've started a thread to talk of them.

I'll start with the "trompe". This is a French word for a pump. But it compresses air using falling water. In effect, it is a form of a RAM pump. It goes way back in history. The ancient Romans could not build air compressors but did invent a pipe organ run with a trompe.

So I had an idea. In a dry, hot climate evaporative cooling is sometimes used. But in a humid, hot climate these devices don't work much at all because the ambient air will not absorb much water vapor since it is close to saturated.

So, if you have falling water, you install a trompe to compress air. When air is compressed, it gets warm. So you run the compressed air pipe back down the stream underwater to cool it. Compressed humid air, when cooled, will probably lose some of its water vapor to condensation. This water is bled off the system leaving cool, relatively dry, compressed air. If this air is released into the atmosphere just in front of an evaporative wet pad through which it is forced by the decompression, we will get two cooling effects. The first results from the decompression of cool air and the second results from the evaporative affect of relatively dry air moving through the wet pad. One should get a blast of cool air. What this is, in effect, is a water powered air conditioner with no real moving parts!

I'm putting this up here just so people know such might be possible. Who knows what could happen!

[Mark Parsons]

Greetings Roy,

Have any reference links for the 'trompe' you mention? I am unfamiliar with the technology - or at least the term.

Compressed air could be used directly to drive an air motor that turns a mechanical air conditioning compressor (heat pump) to get your cool result maybe more efficiently or conveniently than highly ambient constrained evaporative cooling. And of course, if a heat sink is available (like the flowing water that is producing the compressed air) then the heat pump efficiency goes way up.

Thanks
Mark

[Roy Lent]

Hi Mark,

Go see: http://www.motherearthnews.com/Alternative_Energy/1977_July_August/Harness_Hydro_Power_with_a_Trompe

These trompes work fine but the pressure differential can't be very high. But they are so simple and rarely used. Anyone who is in alt energy should be very aware of all possibilities.

[Roy Lent]

Another relatively unused technology is the solar tower. See:

http://www.wentworth.nsw.gov.au/solartower/

This is a proven technology. They built a little one in Spain that worked well. The proposed Australian one would have a tower one kilometer tall, the tallest structure on Earth. And, for me, there lies the problem. The construction of a free standing one Km tall structure is expensive, incredibly so.

A solar tower has numerous advantages. Not only does it produce large amounts of electricity from, basically, the Sun, but it condenses much of the water vapor out of the uprushing air as a liquid. So the outer ring of greenhouses that gather the sun's heat, with this water, could be a good food production area. The water lost to evaporation being recovered at the top.

But to build a tower that high is beyond most people. But what if one went to somewhere like the Atlas Mountains of North Africa and found a steep, South facing mountain side. One could build a cheap plastic tube up the mountain side with green houses below. An inclined tube would have to be less efficient but just extend it even higher. A site for this might also be found in the SW US, not quite that high, but satisfactory. I wonder how much power a one or two hundred meter inclined tower could produce?

I believe that this is a completely new idea so I can not give any sucessful examples, but I feel it to be worth consideration.

[Mark Parsons]

Thank you for the link Roy.
Interesting technology. I've been to Cobalt, Ontario and didn't make the connection with Ragged Chutes Trompe.
I assume the outlet height must be considerably lower than intake to ensure sufficient flow to keep the bubbles moving down. In the Mother Earth News article the outlet head is not stated. If outlet head is 351' deep then max air pressure would be 351 feet / 2.31 feet per PSI = 150PSI max. Not bad.

[Gary Williams]

Last year, there was a one-time internet posting that was passed around to the various renewables blogs but there was never a follow-up posting. Some University kids came up with a device that generates 190 F. water from a 35 bbl metal drum converted to a Savonius windmill. It rotated permanent magnets over a copper plate inside a container lined with a copper tubing heat exchanger. Lots of internet researching led pretty much nowhere – except they’d run up against a problem with excess heat causing magnetic field fading in the magnets, and they expected to solve it any day now. Their device inspired me to wonder…so many questions, like: What about using electromagnetic field coils instead of permanent magnets? What progress have they made? Who else has crafted such a device? One fellow pursued water cavitations successfully using rotational energy and ultrasonic bubble formation as a heat and steam generator. His seems too complicated and costly for me as a DIY project. Obviously, if you stir water or air vigorously, it will heat up.
And since the kids’ approach hit a roadblock, what about using friction generation? I can imagine building a not-too-big crucible furnace, a kiln, some kind of hot box in the backyard. I can see obtaining high temperature furnace brick and insulation, good up to about 2800 F, surrounding it with home-made brick using an ingredients formula developed in Costa Rica, good to about 800 F. Methods of heat generation would include electrical heating element, solar concentrated light beamed through a quartz window, and/or mechanical friction. Seems to me that I might be able to add additional heat from a very efficiently designed wood burning stove built in, getting rid of some of the wind-blown branches in the neighborhood.
Before proceeding to a description of a mechanical friction heater, I would like the group to consider the hot box idea and discuss it. I can imagine using the kiln for primary uses of melting & shaping metals, glass & ceramics work, and secondarily for tapping the heat from the box for hot water for the house, cooking pizza and baking instead of using the oven which heats up our home, causing our a/c to kick on at 17 cents/kWH. What do you think of the hot box idea as an inexpensive but logical energy storage device, perhaps disguised as a terraced garden or something?

[Dave Turpin]

There is definately more than one way to skin a cat. That said, some are definately more efficient than others.

The trompe idea would probably work. However it is a 3-step process to simply use a swamp cooler. If you had access to a waterfall like that, you could generate gobs of electrical power with a turbine. Then you can run whatever you want. Even an air conditioner.

A similar way to make power would be to build a waterwheel coil water pump:
http://lurkertech.com/water/pump/morgan/tripod/

You don't even need a lot of head to make one of those. It moves water AND compresses air.

Wasn't there a solar tower like that in a James Bond movie?

[Penny Walters]

Hey Roy that was a really interesting post that you shared. I wonder if in the near future this type of technology will be taken into consideration by major corporations.

[Peter Mckinlay]

We tend to work with well known mechanisms like solar panels, wind generators, biodigesters or hydro-plants. But there are many more ideas out there, some not too well known. So here I've started a thread to talk of them.

I'll start with the "trompe". This is a French word for a pump. But it compresses air using falling water. In effect, it is a form of a RAM pump. It goes way back in history. The ancient Romans could not build air compressors but did invent a pipe organ run with a trompe.

So I had an idea. In a dry, hot climate evaporative cooling is sometimes used. But in a humid, hot climate these devices don't work much at all because the ambient air will not absorb much water vapor since it is close to saturated.

So, if you have falling water, you install a trompe to compress air. When air is compressed, it gets warm. So you run the compressed air pipe back down the stream underwater to cool it. Compressed humid air, when cooled, will probably lose some of its water vapor to condensation. This water is bled off the system leaving cool, relatively dry, compressed air. If this air is released into the atmosphere just in front of an evaporative wet pad through which it is forced by the decompression, we will get two cooling effects. The first results from the decompression of cool air and the second results from the evaporative affect of relatively dry air moving through the wet pad. One should get a blast of cool air. What this is, in effect, is a water powered air conditioner with no real moving parts!

I'm putting this up here just so people know such might be possible. Who knows what could happen!

Hello Roy,

You are on to it, though you may need look to CO2 the natural Refrigerant. It begin its energy release at -40*C. Heat expansion causes a massive pressure increase beginning at 2 bar pressure and climbing to 10,000 bar pressure at +100*C. Any heat differential causes a pressure force energy applicable to shaft rotation. By fridge physics the CO2 is always returned colder than its departure. The pressure difference between CO2 cold and hot is the pressure force of energy supply.

That attached is for provided heating rather than ambient heating. However it be same mechanism, though without the heating element to raise the CO2 temperature.

Cheers

Peter

Site states I have attached post, yet it not appear. I can do no more!

[Stuart Barley]

Hi all,

I have been toying with an idea of using a trompe for cooling purposes in a freezer but am finding hard to come up with any solid info. So have joined this forum in search of answer!!!

The basic idea is to use a trompe to compress gas then pass it through a vortex generator which should provide the cooling. No moving parts, no electricity, no harmful gas, perfect right?

I only have a 20m head at a push, which is 800m away from the sight. I was wondering if anyone has got experience of using a system for this purpose and if anyone has connecting multiple down pipes into one chamber to increase volume/pressure of the air generated.

Any help input will be greatly appreciate.

[Peter Mckinlay]

Hello Stuart,

That you have outlined is possible but not by a Ram pump but similar.

Ram pumps cause a water hammer by sudden shut off of flow.

This activity can cause gas compression in similar device, however all water is discharged unlike the Ram pump.

From a 20 meter head a compression pressure of 2 bar is obtainable.

Absorption fridge/freezer's work to very low compression pressures.

Water fall compressor does away with heating to obtain compression pressure.

Peter

[Stuart Barley]

Hi peter,

thank you for your response, you have given me some options to think about. The project is for 16m cube cold room that we use to make ice in the horticulture industry. So am really looking for system that will be able to freeze 300 liters a day (or 900 liters every 3 day) in that sort of ratio/capacity.

any idea or help is always welcome

stuart

[Peter Mckinlay]

Hello Stuart,

Feasibility requires more information,

Any fridge/freezer is designed around the volume and pressure of the Refrigerant passing through the restrictor valve.

What is pressure and volume of the present electric compressor you have.

What is the volume of water flow you have.

Peter

[Stuart Barley]

Hi peter,

Apologies for the late response, work has bee hectic, with regards to you questions. The water source is approx. 2m across 0.025m deep and flowing at around 1.5m per second say 50-75 liters (it is the dry season here at the moment but the river water comes from a spring, I expect this will increase but only slightly). With regards to the freezer a lot of the information has faded on some panels but I have attached a picture of the one remaining I hope it helps.

A little bit of back ground info it may help or not. I was asked to come up with ways to save electricity. so there were 3 thing I was looking into.

Cold store - trompe with a vortex tube which we have discussed.

river pump - thinking of a water wheel spiral pump

Electrical generation - waste (woody) biomass, made into pellet form, gasification to produce steam then a turbine generator set. Approx. size 150 Kva.

The river is around 40m below the farm. We dammed it may years ago. may be 50m across with the water extending back may be 100 - 150m. The height of the water must be 6-7m with the ground dropping of more as it goes down the valley. The idea would be to cut into the ground a run of trench which I believe would be possible to get somewhere between 15 - 20 m head if necessary.

Kind Regards

[Stuart Barley]

Hi Again,

Just a thought I have had. If a spiral pump was to be used could you attach a trompe like device on the outlet so you could harvest the compressed gas from there?

Any thoughts?

[Peter Mckinlay]

Hi peter,

Apologies for the late response, work has bee hectic, with regards to you questions. The water source is approx. 2m across 0.025m deep and flowing at around 1.5m per second say 50-75 liters (it is the dry season here at the moment but the river water comes from a spring, I expect this will increase but only slightly). With regards to the freezer a lot of the information has faded on some panels but I have attached a picture of the one remaining I hope it helps.

A little bit of back ground info it may help or not. I was asked to come up with ways to save electricity. so there were 3 thing I was looking into.

Cold store - trompe with a vortex tube which we have discussed.

river pump - thinking of a water wheel spiral pump

Electrical generation - waste (woody) biomass, made into pellet form, gasification to produce steam then a turbine generator set. Approx. size 150 Kva.

The river is around 40m below the farm. We dammed it may years ago. may be 50m across with the water extending back may be 100 - 150m. The height of the water must be 6-7m with the ground dropping of more as it goes down the valley. The idea would be to cut into the ground a run of trench which I believe would be possible to get somewhere between 15 - 20 m head if necessary.

Kind Regards

Hello Stuart,

Good info thanks. The stream flow allows 50 litres per second. This can be converted to 50 litres per second flowing through the restrictor valve in your freezer. However your freezer shall have been designed for x litres of refrigerant per second at x pressure. This would need be known if the electric compressor is to be replaced by stream flow.

The greater the volume and higher the pressure the Refrigerant passes through the restrictor valve the greater the heat loss. To achieve what your asking may require a new engine etc but not cabinet.

Sorry but a water wheel and Archimedes screw not give any greater water head but lesser due to the energy taken to drive the Archimedes screw.

As for a 75Kw generator of low heat requirements you may to look for or self build one of many DaS Energy CO2 energy conversion devices.

Attachment not possible without a URL so you may wish to private email.

Peter

[Greg Felix]

These are great ideas! I'm just getting started with DIY green living, and you've all been incredible help. Awesomeness.

[Chuck Roberts]

I've several videos of the trompe on Youtube, which is basically a self-powered water pump. One pump had water flowing through a stream and the water squirted 5ft above the stream surface, more than enough to pipe the water to another pipe to carry it towards a house or barn.

While 80% of the water flowing by is used to power the thing, you still get more than enough water pressure to pump it horizontally. I don't know the limit of the distance if you were pumping uphill.

[Peter Mckinlay]

Hello Stuart,

Good info thanks. The stream flow allows 50 litres per second. This can be converted to 50 litres per second flowing through the restrictor valve in your freezer. However your freezer shall have been designed for x litres of refrigerant per second at x pressure. This would need be known if the electric compressor is to be replaced by stream flow.

The greater the volume and higher the pressure the Refrigerant passes through the restrictor valve the greater the heat loss. To achieve what your asking may require a new engine etc but not cabinet.

Sorry but a water wheel and Archimedes screw not give any greater water head but lesser due to the energy taken to drive the Archimedes screw.

As for a 75Kw generator of low heat requirements you may to look for or self build one of many DaS Energy CO2 energy conversion devices.

Attachment not possible without a URL so you may wish to private email.

Peter

Hello Stuart, thank you for your information. In Australia such pump is known as a RAM pump. Your idea of using water flow to generate electricity to power a Fridge compressor is most viable. A Banki turbine requires a one litre flow per second at 9 bar pressure to produce 720 Watts. The CO2 turbine engages heat to increase the expansion pressure of the CO2. Whilst a water flow can be used to drive a turbine driving the Fridge compressor to drive a generator , that same water flow force may be used directly to generate electricity. Not included information in the original post is CO2 heat expansion commences at -47*C. So long as the chill side is lower temperature than the hot side power shall be produced. CO2 pressure to temperature scale is web available (unfortunately a computer loss has seen I regathering that information), thank you again for sharing the information you have, Peter

[Peter Mckinlay]

Hello Stuart,

Good info thanks. The stream flow allows 50 litres per second. This can be converted to 50 litres per second flowing through the restrictor valve in your freezer. However your freezer shall have been designed for x litres of refrigerant per second at x pressure. This would need be known if the electric compressor is to be replaced by stream flow.

The greater the volume and higher the pressure the Refrigerant passes through the restrictor valve the greater the heat loss. To achieve what your asking may require a new engine etc but not cabinet.

Sorry but a water wheel and Archimedes screw not give any greater water head but lesser due to the energy taken to drive the Archimedes screw.

As for a 75Kw generator of low heat requirements you may to look for or self build one of many DaS Energy CO2 energy conversion devices.

Attachment not possible without a URL so you may wish to private email.

Peter

Hello Stuart, this Peter is not the Peter in the post. It agreed a screw pump not increase water pressure and was never intended to. It be a simple Steam boiler refill pump. It be correct the greater the CO2 pressure and flow the greater the power produced by the turbine. The loss off energy in doing this reduces the CO2 temperature, however not enough so the CO2 is back to start temperature.