Water power for your machines

[vic neweyParticipant @vicnewey60017]

I though this was rather amusing, a water power motor for your machines , I would think it would be rather feeble and struggle to run a sewing machine and not a good idea if you have a water meter

[vic neweyParticipant @vicnewey60017]

[noel shelleyParticipant @noelshelley55608]

This reminds me of a tale told by a friend during the power cuts of I think 1973? Of how his neighbour made a small water turbine to drive a small dynamo so he some light in the evenings ! No water meters in those days ! Noel.

[John HaineParticipant @johnhaine32865]

In (I think) a Manchester industrial museum located in an old textile mill, the clocks were run off the line shaft that were driven by water power. As the water went down, the shafts went slower, so the shifts got longer!

[Ian ParkinParticipant @ianparkin39383]

Manchester apparently had a power delivery system running on water…highish pressure water was supplied to your premises and you could use that to run machines ,generate electricity or power lifts..

[Rob McSweeneyParticipant @robmcsweeney81205]

Back in the day, it was fairly common for church pipe organs to be be blown by mains water operated pumps. At the other end of the scale – does anyone remember the little water turbines that were sold to power Meccano models? Iirc the makers of those also sold a powered toothbrush driven by the same or similar turbine.

[SillyOldDufferModerator @sillyoldduffer]

As a way of estimating the power available from a tap, this attempt may be wrong! Any comments?

I measured how long it took to fill a 1 litre container from the kitchen tap. About 4 seconds.

1 litre of water weighs 1kg and my home is about 100metres above sea-level.

In Metre Kilogram Seconds metric, power is:

Watts = Mass x height x time

Watts = 1kg x 100m x 4s

About 400W available to drive the motor.

Assuming water motors to be 20% efficient, one would output about 80W of usable energy, enough to run a Singer type sewing machine, but not enough to usefully power an ML7! Used to generate electricity at 50% efficiency, 80W out would be enough to power a 40W filament bulb well enough to read or work in small kitchen. 40W of LED light would brightly light a small workshop.

Water motors were popular before mains electricity became common, and I believe they were eventually forbidden by most Water Boards. The problem is where the energy comes from. The energy is only free if one lives below a reservoir that's filled naturally by rainwater. Most homes are fed by water pumped from a low lying reservoir into higher tanks. Pumps were originally powered by steam engines, these days big electric motors, but either way a home water motor is powered by a big engine at the water works. Domestic water is a wasteful way of making power, as anyone with a water meter will confirm!

Hydraulic power systems worked somewhat differently. Water was pumped at high-pressure around a closed loop, and it was easy to meter how much power each customer was using, so they paid for it! Quite a good system, but hard to extend because it depends on high-pressure pipework, which is harder to upgrade and reroute than electric cables, and a national grid system is impractical.

Dave

[duncan webster 1Participant @duncanwebster1]

your height above sea level is immaterial, what matters is the pressure in the water main. This varies wildly, at my in-law's house they couldn't have a shower upstairs as the pressure was too low to give the required flow rate. Water only just staggered out of the taps. I have a feeling that you're not supposed to attach a pump inlet to the mains as reducing the pressure in the main to below that outside could suck contaminants into the pipe. We get away with it on pressure washers because no-one knows, and they are fairly low flow rate , so unlikely to cause an issue.

It's not straightforward to work out available power, as when you open the tap the pressure just upstream of it falls due to losses in the pipework, the higher the flow the greater the losses. There will be a sweet spot somewhere which maximises power available

[roy entwistleParticipant @royentwistle24699]

A lot of cotton and woollen mills had water tanks on the roof mainly to guarantee water for the boiler, but also for the fire sprinkler system and water powered hoists

Roy

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Ian Parkin on 11/01/2023 11:24:42:

Manchester apparently had a power delivery system running on water…highish pressure water was supplied to your premises and you could use that to run machines ,generate electricity or power lifts..

.

See posts on this previous thread: **LINK**

https://www.model-engineer.co.uk/forums/postings.asp?th=173115&p=2

MichaelG.

[Nigel Graham 2Participant @nigelgraham2]

In the early days of broadcasting you could buy dedicated, small turbo-dynamos in the same style, for recharging your wireless-set's accumulator.

I've an idea I have seen advertisements for them in old editions of Model Engineer.

The scullery tap might have been enough for a sewing-machine water-motor but would never have powered your workshop, but that didn't matter. Instead the energy for that was "renewable" as they say now without concern for basic physics. For your lathe of course was powered by treadle, a handle on a flywheel rotated your bench-drill spindle, and the shaper had a lever resembling a beer-engine on its side to give you muscles like a barmaid's.

(My shaper is indeed of that venerable pattern and patina; though I'm not sure that description quite matches its operator. More like frayed round the edges, and muscles our Mam would have likened to "sparrer's kneecaps". Obviously I should do more shaping and less milling.)

[SillyOldDufferModerator @sillyoldduffer]

Posted by duncan webster on 11/01/2023 13:30:06:

your height above sea level is immaterial, what matters is the pressure in the water main. …

…

My logic is enough energy had been put into the system to lift my tap water 100m up above where it exhausts, in the sea. I hoped the numbers were about right in terms of potential energy, admittedly ignoring pressure in the main.

Thinking local circumstances through though, my water almost certainly comes from a hilltop tank, which is 100m higher than my home. The water is probably pumped from Chew Valley Lake, which is roughly 50m asl.

Pressure = Density of Liquid x Height x Gravity Acceleration

In MKS, Density of water is 1000kg/cubic metre. Height is 100m, and Gravity is 9.81m/s/s (all it 10!)

So pressure at my tap could be:

P = 1000 * 100 * 10 = 1000000 Pascals

It isn't! 1000000Pa is 10 bar or about 145psi is much higher than I get. The water company must be regulating the pressure. Based on the force water comes out of my bathroom cold tap, my guess is it's between 1 and 2 bar, something near 20psi.

So if 1kg of water comes out of a tap in 4 seconds at 1 bar, what's that in Watts?

My brain hurts. Might try again after a strong coffee!

I should be doing something productive…

Dave

[egaParticipant @ega]

Some years ago mains water-driven pumps for evacuating veneering bags were in use.

[VicParticipant @vic]

I’ve never seen one but one of my old bosses told me they had a water powered vacuum pump of some sort where he worked many years ago. It was for contact printing and it did indeed run off the mains water supply.

[Michael GilliganParticipant @michaelgilligan61133]

Back in Schooldays, we had little ‘aspirator pumps’ attached to the taps on the lab-benches

This video shows how to make one from modern plumbing fittings

**LINK** https://youtu.be/_6PNs9TQ44g

MichaelG.

.

People with workshops might well do it differently … but I admire his initiative ! 

Edited By Michael Gilligan on 11/01/2023 17:24:08

[egaParticipant @ega]

Would I be right in thinking that the OP's illustration is of a Peltier wheel-based device?

[Jim GuthrieParticipant @jimguthrie82658]

Posted by Rob McSweeney on 11/01/2023 12:05:45:

Back in the day, it was fairly common for church pipe organs to be be blown by mains water operated pumps.

My father was organist in a church with a water operated blower for a large three manual Lewis. By the mid-50s the operation of the engine was getting distinctly problematic and was only kept going by the ministrations of the chief engineer from the power house in the local disillery, a colleague of my father. It was supposed to have a start stop remote control by the manuals but that had stopped working and the engine was started just before the service and left running till the end. The whole service was accompanied by the creaking and groaning of the engine. This noise did have one advantage in that it indicated when the engine had stalled, which was frequent and my job as a youngster was to climb up into the organ loft and kick the valve to re-start it, and stand well back as it took off restoring pressure.

It saw its end in the 1950s when there was a long dry spell with restrictions on water use and the church had to make do with a piano. My father persuaded the church to install an electric blower and it appeared not long after.

Jim.

Edited By Jim Guthrie on 11/01/2023 17:20:58

Edited By Jim Guthrie on 11/01/2023 17:21:52

[SillyOldDufferModerator @sillyoldduffer]

Posted by Vic on 11/01/2023 16:44:17:

I’ve never seen one but one of my old bosses told me they had a water powered vacuum pump of some sort where he worked many years ago. It was for contact printing and it did indeed run off the mains water supply.

One of these perhaps?

They were commonplace lab equipment when I did Chemistry at school. The example above may look cheap plastic but it costs £75!

Not much to them. Tap water enters at the top, is forced into a jet by a cone, and sprays out through the down-tube into a sink. The jet passes through a chamber, to which a side nozzle is added. The mass of water flying past at high speed entrains air and pulls it out of the chamber to create a useful vacuum. A rubber tube connects this to whatever apparatus needs a moderate continuous vacuum.

Not powerful, but convenient, chemical resistant, and idiot schoolboy proof! Only used twice to my recollection. Once to speed filtration, the other time to quickly evaporate an alcohol solution to get a precipitate. Can't remember why, I was probably thinking about girls…

Dave

[Nigel Graham 2Participant @nigelgraham2]

EGA-

I think you mean "Pelton", but it most likely is of that form. ("Peltier" is the name of the heat-tranferring effect of a type of transistor.)

'

In the late-19 / early 20C an enormous amount of work was done on water-turbines for driving machinery, though industrially, using rivers. The two basic situations are of high head / (relatively) low flow for which the impulse Pelton runner is ideal, or of low head / high flow better handled with Kaplan-pattern (propellor-like) and various other reaction turbines.

A text-book I have from that period concludes its chapter on water-turbine types and design calculations, by confidently asserting the world's rivers contain enough power for everyone! It hedge its bets though. Longer chapters teach us how to design reciprocating steam-engines and boilers.

[Neil WyattModerator @neilwyatt]

Coincidentally I found this in my 'archive of interesting things' yesterday:

Neil

[Michael GilliganParticipant @michaelgilligan61133]

Here’s a nice tidy one, with some decent drawings : **LINK**

https://worldwide.espacenet.com/patent/search?q=pn%3DGB189415255A

MicaelG.

[Nigel Graham 2Participant @nigelgraham2]

A bit worrying that among the butchers, carpenters and general mechanics, dentists would also find invaluable, an off-hand grinder with no tool-rest and supported apparently only by the turbine's attachment to the tap….

.

The Bray patent application is interesting but to succeed he would have needed prove novelty of design, not of "improvement".

His is a simple Pelton turbine but what would appear to be his claim is fundamentally flawed.

The true Pelton "bucket" (yes, it is called that) is a twin component like a pair of spoons side-by side. The central wall is sharp, and exactly on the centre-line of the single nozzle. There may be more than one nozzle per turbine, but only one per bucket.

The result is that the water divides into two equal streams flowing down their own sides of the wall to impinge on the bottom of the bucket – impulse action.

The spoon shape of the bucket then reverses each stream by somewhere around 150º or so, making it leave the bucket somewhat to the side of the wheel, and possibly giving a reaction component.

This smooth reversal extracts the bulk of the jet's potential energy.

The bucket usually also has a semicircular notch in its rim. I take it that this eases its movement into the jet at the best angle.

Bray's provision of two nozzles means the water will hit the bucket close to the bottom of the "spoon", making the reversal less efficient. Further, some of the water would rebound up the central wall, so the two jets would interfere with each other.

He would have been better, perhaps, using two single nozzles on opposite sides, but I doubt he could have patented that. Many large industrial turbines were built with multiple nozzles, each with its own valve, for speed control.

'

I have seen a small grain-mill driven by two very simple reaction-turbines. Located in the Pyrennean foothills, it was clearly preserved and open to visitors, but closed when we saw it. Even so, I managed to paddle into the large, arched tail-race to inspect the two turbines, of open construction.

Bright shiny stainless-steel bolts contrasted with the dark cast and wrought irons, showing recent repairs.

The runner resembled a simple extractor-fan. .An iron ring maybe 150 mm deep (this is France!) by 500mm diameter, having four, rigid, "spoke" vanes inclined at 45º to the plane of the wheel. The wheels are on vertical shafts rising through the floor above, perhaps driving the stones directly rather than through gears.

The water simply falls onto the turbines from curved elbows protruding from the wall, with their sluices or valves presumably in the mill, built basically on the dam. The head (from memory) would be about 3 or 4 metres.

I spotted a large salamander in the shallow tail-race water.

[duncan webster 1Participant @duncanwebster1]

Posted by SillyOldDuffer on 11/01/2023 16:33:10:

Posted by duncan webster on 11/01/2023 13:30:06:

your height above sea level is immaterial, what matters is the pressure in the water main. …

…

My logic is enough energy had been put into the system to lift my tap water 100m up above where it exhausts, in the sea. I hoped the numbers were about right in terms of potential energy, admittedly ignoring pressure in the main.

Thinking local circumstances through though, my water almost certainly comes from a hilltop tank, which is 100m higher than my home. The water is probably pumped from Chew Valley Lake, which is roughly 50m asl.

Pressure = Density of Liquid x Height x Gravity Acceleration

In MKS, Density of water is 1000kg/cubic metre. Height is 100m, and Gravity is 9.81m/s/s (all it 10!)

So pressure at my tap could be:

P = 1000 * 100 * 10 = 1000000 Pascals

It isn't! 1000000Pa is 10 bar or about 145psi is much higher than I get. The water company must be regulating the pressure. Based on the force water comes out of my bathroom cold tap, my guess is it's between 1 and 2 bar, something near 20psi.

So if 1kg of water comes out of a tap in 4 seconds at 1 bar, what's that in Watts?

My brain hurts. Might try again after a strong coffee!

I should be doing something productive…

Dave

According to the interweb there should be a pressure regulator in every house just after the stop tap. I've never seen on in any of the houses I've lived in, but if the mains pressure is below about 3 bar you wouldn't need one. Even without a reducing valve, you'd only see the full head if no-one was running a tap, so no pressure drop in the pipes.

[egaParticipant @ega]

Nigel Graham 2 and MichaelG:

Thanks for pouring cold water on my Peltier! And for those unusually fine drawings.

[Michael GilliganParticipant @michaelgilligan61133]

This business of ‘head’ is interesting …and I think the missing factor is probably the inevitable frictional loss in the very long pipes.

As an aside … I once had to do an immersion test on a piece of military hardware to [if I recall correctly] eight foot depth. As an innovative cost-saving, we put a good strong lid on a domestic [grey plastic] cold-water tank and added a vertical ‘stack’ of plastic drain-pipe. … the bulging sides of the tank were an adequate demonstration that the head was effective [because the aspect-ratio [bore/length] was sufficient to make the friction trivial].

MichaelG.

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