is quite common to confuse Hydrostatic power with Hydrodynamics, confusion of excessive expectations which arise in the presence of " running water." A single stream or even a river plain, contrary to what might be expected, is not a useful source of energy to be converted into electricity. other hand, a small shed at a rate of only one liter per second but with a good drop can be a solution for individual self-generation.
We assume that the fluid dynamic energy is:
Where as we had seen,
d = density of fluid in kg / m 3
S = cross section of the fluid in
; ; movement m 2
v = velocity in m / sec
For water d = 1000 kg / m 3 thus
From In practical terms, a river with a current order of meters per second, it implies a fall equivalent to 5 cm
From 
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but this should not be confused with the slope of the river bed or canal, confusion often occurs that gives the problem and excessive expectations.
The hydropower, solar energy conversion by natural means, as we have seen a million times *, usually presenting as hydrostatic , thanks to evaporation process, lifting and moving inland water and ocean, which eventually will be deposited from hundreds to thousands of meters above sea \u200b\u200blevel, which returned transforming that potential energy , indeed negligible in kinetic energy. This in turn, is degraded in friction, unless the man conscious of his power in his path control devices, read dikes or dams, so take advantage of it. In a way, these
reservoirs act as accumulators, transforming potential into kinetic energy as needed and avoiding wasted naturally. 
To get an idea of values \u200b\u200bthat assume this natural process, let us take an example: Suppose the Lanin Volcano, a snow or rain falls of 100 mm. and that the area covered by the "cone" is the corresponding to a diameter of about 25 km, with the height of 3700 meters the potential energy of the precipitation is around 200 million Kwhora, energy equivalent to 5% of monthly consumption across the country. The potential energy of the Limay basin, whose origin is known is the Nahuel Huapi, is capable of delivering less than 500 km of travel over 2500 MW, equivalent to more than 20% of total consumption in the country. From its origin to its confluence with the Rio Neuquén giving rise to Black, the fall of Limay is 500 meters, bringing the average gradient is 500 / 500,000, or 1 per thousand (0.001). To exploit this fall should make 100% in Neuquén dam 500 meters high, a true utopia for two reasons, the lake would inundate half Patagonia and resistance of the wall should be immense. Another alternative would be to break that point on 5.6 or 10 heights ... so equivalent to solve both problems.
lakes would be more reasonable, there would be the river, because the edge of the wall of a dike along the lake would come next. With that achieved a 100% return failing hydraulic water movement out of the turbines. That is the reality and see what happens tendencia.Ahora the Black River. The slope is very different: 300 meters at a distance of 700 km. The business is not the same. The topography of the land
is not the same, the mountains are no longer helpful as natural dams, lakes would be extremely large. The potential energy in the absence of water containing who is transformed into kinetic lost completely. Intuitively, a producer over the banks adjacent to dream of obtaining that benefit. Is available energy, as solar radiation and a lot ... but let's see what happens to our purposes. As discussed, the kinetic energy available is:
and although the rate depends on location, we can take extreme values \u200b\u200branging from meters to 2.5 m / s. This means, for example, that we need 2 square meters with a current theoretical one meter per second for a power of 1kW. Zuppinger A wheel type, similar to the mechanism of promotion of the old ships of the Mississippi, tour currently in use in many lakes in the world, should have no less than 10 meters wide with 50 cm depth which already gives us an idea as impracticable, under the economic point of view. Improving the speed, using natural locations where slopes located narrowing or increased to twice that speed, would lose a quarter of the width of the wheel is 2.5 meters. However, compared with devices that convert the potential energy, kinetic rather than force us to think about how impossible the dynamic use: an artesian well, a spring or spring of 100 meters at a rate only 1 liter per second gives the same theoretical capacity of 2000 liters / sec required to take a stream of 1 m / sec. Once again, nature takes care of collecting, underground, in huge "underground pools" a modest hydrostatic potential, ideal for the individual adequate supply of energy capable of meeting the consumption of a family away from the centers of power distribution Community. The expectation with respect to the hydrodynamic advantage is not very reasonable. The question that immediately arises is it not possible then, and transform dynamic potential energy in the jump of 100 meters and only one liter per second of flow, do the opposite with a dynamic flow of thousands of liters? The answer has two aspects, the technical and economic asserts that denied. The investment required to achieve that purpose is of such magnitude that only becomes feasible in very few cases. We try to show, for which as a starting point we must return to the first paragraphs. Calculate the slope of the current that corresponds to the speed of the stream we want to exploit. Applying Bernoulli's theorem and supported by Bazin, Kutter and Ganguillet, Weischman and other specialists in the field, we know that la perdida de carga h de un tramo de río con pendiente i , de longitud l , con un radio hidráulico r= F/U donde F es la Sección del torrente y U el perímetro mojado, con velocidad media v , etc. etc. es
which shows that
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In conclusion it can be argued that trying to transform the velocity of water in another form of energy is not suitable for speeds of the order of a few meters per second. Measuring the speed of the stream may take a few minutes. Appreciation visual of it is simple and it allows an immediate analysis of the situation. Reasonable slope to take advantage of this energy should be allowed to gain several hundred feet in meters rather than thousands, which makes the slope of the course to be a waterfall, noticeable to the naked eye. "Several meters" split "several hundreds of meters" means talking about a pending order of% instead of 0 / 00 as it emerges from the above analysis. To double the speed of the water means quadruple the slope. To achieve interesting speeds necessary to harness the kinetic energy of water is needed, pending the conclusion very important, but ultimately when such steep gradients are associated with significant flows, the most reasonable is to transform kinetic energy into potential through a dam, obtaining by this means, fulfill other required parameter which we have discussed repeatedly, to earn. At this point one can differentiate the integral use of energy, ie community use, compared to the attitude of partial use, intended for individuals surrounding the
coastal rivers. For these cases say that there are special micro but of such low power, for example the order of 100 watts for speeds of around 2 to 3 meters per second.
The last aspect is related to tourism. When water velocities are important, as we saw, a synonym for jump, is associated to the energy problem in assessing the beauty of nature and economic evaluation of the subject. Who would ever turn to Niagara Falls in a hydroelectric plant?
NOTE
The original speech, responding to repeated inquiries from neighboring farmers on the banks of Black River and Colorado was synthesized, adapting the television space available. But questions arose subsequently, many of them specialists in the field colleagues who requested clarification. This note is intended to cover all aspects relevant to the demonstrations, at the risk of complicating the understanding of the whole or limit the readership. I ask those not familiar with formulas, ignore skipping rows and reading only generalities.
Many thanks.
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recommend access to Google search by entering the search word followed by enrique nielsen. Eg energy enrique nielsen
Mr. Enrique O. Nielsen recommend access to Google search by entering the search word followed by enrique nielsen. Eg energy enrique nielsen
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