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Marcel Haenggi


There were interesting systems of direct use of hydro power at Lake of Zurich (and probably elsewhere) in late 19th century. In the heights close to the villages there were little artificial lakes ("Weiher") which provided a network of pipelines with high pressure water. Any factory or crafts workshop in the village could get connected to the system for a fee. The water than powered the machines. On sundays when factories did not work, the water was used for waterspou fountains, some of which still are active today or have been re-established (e.g. in Richterswil: http://www.fontaene.ch/typo3temp/pics/5f7b1245bd.jpg ; http://www.fontaene.ch/typo3temp/pics/a70c569059.jpg ; http://farm6.staticflickr.com/5106/5628095345_7e53a35a78_z.jpg).

Alfred Max Hofbauer


Hi Kris!

A flow of water through a pipe is as much energy as a flow of electrons in a wire. There is no compelling reason why it shouldn´t be possible to have a lamp working on waterpower... or on compressed air, mechanical work, etc.
The method has not been developed yet, but it should proove interesting to do so...



Nice article about rotary hydropower.

i was swimming in the lake today. In the bath the have a small lift. It is used to lift handicapped people in and out the water. The lift is powered with water from a garden hose. Basically the lift is an hydraulic cylinder with two valves and a chair attached to it.

Many machines use hydraulic or pneumatic cylinders. Electric cylinders are still expensive. With hydraulic cylinders we can power lifts, rams, scissors, presses, dumpers, gates, cranes and much more.
Many tools are still operated pneumatically which is the most expensive form of energy. £he could be constructed to run with water.

Look at modern construction machines like an excavator. The diesel prime mover is powering the hydraulics. The caterpillars are powered by hydraulic motors and all the rest by hydraulic cylinders. If we have enough pressure it should be possible to convert a machine from oil hydraulic to water. With a flexible hose it would be possible to operate construction machines. Houses bridges and tunnels could be built just with water hydraulics.

Kris De Decker


@ Marcel: That's correct. These and other systems will be discussed in the next post.

@ Alfred: Interesting. I thought that a light bulb required electricity. An LED does for sure, because its operation is based on moving electrons. The same goes for computerchips. Whatever power source you use, you will always have to convert the energy to electricity. Are non-LED light bulbs different?

@ Matthias: Exactly. See upcoming post.

Alfred Max Hofbauer


Any kind of energy can be transformed into any other kind... Here is a list of the known types: http://en.wikipedia.org/wiki/List_of_light_sources
I´ve been trying sonoluminescence and triboluminescence (even into the X-ray spectrum).
A friend of mine made a "hydraulic LED", years ago, drilling a T-junction of hydraulic lines into a block of clear plexiglass. It lit only when the flow ran in one direction.

Laurent S


There is a loss when you produce electricity, but you can use electricity anywhere. Direct hydropower means that you have to carry the wood, the seeds,... to the hydropower plant, and then you will also lose a lot of energy. So the ratio win/loss is more complex to calculate.



Did you know that electric motors are the single biggest users of electricity in the world; using almost half of all of the world's electricity. I would agree with you that, in some instances, using mechanical energy from a turbine/waterwheel to generate electricity to power a motor and turn the energy back into mechanicl energy is slightly stupid. However, I would add that, in my opinion, this mechanical energy might not be as easy to transmit as electricity over distances of more than several metres or to serve multiply users at once and inconsistent load that are continually coming on and offline and/or changing speeds. The resaon why I think that most hydropower projects are for hydroelectricity is be more flexible and possibly user friendly because a river won't light your house and you can't recharge a cellphone with a stream



Water wheels are great but not everyone has a stream and a good head of water. A deep well and a small head of water can be used to compress air in a "trompe". Bubbles flow down and are compressed and captured in an air chamber. The deeper the well the higher the pressure. The greater the head the faster the flow. Compressed air is versatile and since it is expensive if produced by electricity a deep well trompe might be worth drilling.



electricity won the role of the transportation of energy, not the production of it, as is shown with small hydro energy too

with the image above, in the article, we are locked having a stream with a given head fall and water amount, which may not be accessible where it just needed - the wire can be used to transport it to the right location, time, and size

however, i like the idea for direct mechanical use of water energia, but rather as energy storage, than energy production

so, i have an intermittern energy source, let it be an own wind mill, off-peak grid electrical energy, or a combuston engine running on wood gas

i can use the mechanical primary energy to pump up water to give it a height based energy, and then when i use it, release it down, through water wheels, either reproducing electricity again, or use it directly

j walker


You may be interested in this:


he's a retired Electrical Engineer living in Chile who set up his own 4kw hydro plant essentially from scratch with help from 2 or 3 other people. It's pretty amazing.



Paul's comment [7] is partly correct. At least a third of those electric motors are actually pumps of one sort or another. Either moving fluid or air. Heating or cooling buildings, especially commercial buildings. Luddites also have a problem with trying to accommodate commercial enterprise of today's size and breadth - running out of sites for hydropower torque quickly.

Trying to replace electricity in any serious production of commodities, sale and use, is hilarious.



the problem with direct mechanical power is always about power transmission limiting the distance from the power source to the factory itself.

as you yourself wrote about, you got stagenkunst, jerker lines, then you have pulley lines as used for older streetcars. power can physically transmitted over distance in mechanical form by pulling or pushing. as spinning direct drive shafts cannot extend for any meaningful distance .

given this is the case, you either have a problem of having to build a factory on site, or needing to first convert the energy to electrical form for sending it a few kilometers to the location for building the factory.
this is why and how the design of hydroelectric damns make sense.

mechanical direct hydropower is obviously superior as is any direct power method. but direct power is too limiting and is thus superior only in the very narrow number of situations where it can be made useful RELATIVE to those made possible by hydroelectric power generation.

articles like these just contextualize technology in order to emphasize the superior aspects of simpler technologies....



Perhaps it would make more sense to say that Direct hydropower is more efficient "in the moment". This would clarify its true advantages, while simultaneously admitting to its disadvantages.
Unless a Direct hydro plant such as the one in Nicaragua is Depulping coffee 24 hours a day, 365 days a year, then all of those hours of non-productive time begin to add up considerably and completely erode any inherent advantage of momentary efficiency.
Even if one considered the low end of the spectrum of efficiencies for a small battery and inverter hydro electric plant(30%), when one considers the overall productivity thru time for the plant, electric plants will usually come out way, way ahead since they can store the electricity in batteries.
In addition, almost all small hydro electric plants have diversion capabilities, so that as the batteries themselves get full, then any excess electricity is diverted to a whole suite of other potential uses, such as hot water heating.
You did reference these potentials in your article - of using surplus water power to run all sorts of electrical devices.
Once again, my recommendation would be not to say that "Direct Hydro is more efficient", because for 99% of cases, this simply is not true.
But instead to say that "Direct Hydro is more efficient in the moment".
Combine this fact with the fact mentioned by other commenters about the advantages to Hydro electric for power transmission, and hydro electric just runs circles around direct transmission.
Of course, what is left for Direct Hydro beyond any momentary advantage in efficiency is the much cheaper up front capital costs - as you mentioned - which is admittedly a huge advantage to many folks in the world.
Thanks for the article.



It is possible to Increase the efficiency of transmitting water by lowering the velocity of the water through the tube. larger tubes are also more efficient do to the lower the ratio of surface to volume. So by making the pipe larger in diameter than minimally necessary for the volume of water you get a more efficient flow both from the lower velocity and the greater efficiency of the pipe.



@ 11 Eideard

You are really unable to get out of the box. It's tragic really. Do you also complain when someone is so greedy that he finds a use for all the byproducts of his operation and stops dumping waste into a river?

John Paul


35 m of head and 300 L/s flow gives almost 100 kW of power so there's power to spare here.

800 W (mechanical) for $1900 isn't much of a bargain with 1500 W (electrical) turbines going for $1600 (2016). An 800 W electric motor costs a few hundred dollars.

The opportunity cost here is pretty big since the mechanical system can only be used for one purpose and probably for only 8-12 hours per day.

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