Hydroelectric Power - Water power - micro hydro systems
hydro power is probably the least common of the three readily used renewable
energy sources, but it has the potential to produce the most power, more
reliably than solar
or wind power if
you have the right site. This means having access to a river or creek that
has a high enough flow to produce useable power for a good part of the year.
Many creeks and rivers are permanent, ie, they never dry up, and these
are the most suitable for micro-hydro power production.
A micro hydro turbine can take several forms, the most widely recognized
of which would be the water wheel, used extensively for grain grinding up
until this century. Waterwheels are still used in some situations that do
not require a fast-spinning turbine, such as for pumping water. However,
other type of turbines have become quite common.
Image provided by Bernard Bélisle <firstname.lastname@example.org>
The most common of these newer turbines is the Pelton wheel, which is
basically a series of cups attached to a hub. A jet of water is aimed at the
cups, and the resulting force on the cups causes the turbine to spin.
Other types of turbines include the Turgo, Crossflow and various axial
flow turbines, where the shaft through the center of the turbine runs in the
same direction as the water flow, much like a boat propeller.
Water turbines have many advantages over solar panels or wind turbines,
the most obvious of which is that they produce power continuously, 24 hours
per day. However, they also have some associated problems or requirements.
The most important of these is correct siting of the turbine and associated
equipment so as to cause the least environmental damage as possible. Placing
a large concrete dam across a creek or river can do considerable damage to
the surrounding ecology. A general rule of thumb is to not divert more than
20% of the water flow of the creek through your turbine, and to return any
diverted water back to the creek just below the turbine.
Other requirements that must be considered are flood protection for the
turbine and how to transmit the power to the batteries, which may often be
located a long way from the water source.
Turning water's mechanical energy into electricity
Since the time of ancient Egypt, people have used the energy in flowing
water to operate machinery and grind grain and corn. However, hydropower had
a greater influence on people's lives during the 20th century than at any
other time in history. Hydropower played a major role in making the wonders
of electricity a part of everyday life and helped spur industrial
development. Hydropower continues to produce 24 percent of the world's
electricity and supply more than 1 billion people with power.
Evolution of Hydropower
The first hydroelectric power plant was built in 1882 in Appleton, Wisconsin
to provide 12.5 kilowatts to light two paper mills and a home. Today's
hydropower plants generally range in size from several hundred kilowatts to
several hundred megawatts, but a few mammoth plants have capacities up to
10,000 megawatts and supply electricity to millions of people.
Worldwide, hydropower plants have acombined capacity of 675,000 megawatts
and annually produce over 2.3 trillion kilowatt-hours of electricity, the
energy equivalent of 3.6 billion barrels of oil.
Hydropower in the U.S.
With a capacity of more than 92,000 mega-watts— enough electricity to meet
the energy needs of 28 million households—the U.S. is the world's leading
hydropower producer. Hydropower supplies 9 percent of the country's
electricity and accounts for 49 percent of all renewable energy used in the
The nation's largest hydropower plant is the 7,600 megawatt Grand Coulee
power station on the Columbia River in Washington State. The plant is being
upscaled to 10,080 megawatts, which will place it second in the world behind
a colossal 13,320 megawatt plant in Brazil.
How Hydropower Works
Hydropower converts the energy in flowing water into electricity. The
quantity of electricity generated is determined by the volume of water flow
and the amount of "head" (the height from turbines in the power plant to the
water surface) created by the dam. The greater the flow and head, the more
A typical hydropower plant includes a dam, reservoir, penstocks (pipes),
a powerhouse and an electrical power substation. The dam stores water and
creates the head; penstocks carry water from the reservoir to turbines
inside the powerhouse; the water rotates the turbines, which drive
generators that produce electricity. The electricity is then transmitted to
a substation where transformers increase voltage to allow transmission to
homes, businesses and factories.
Types of Hydropower Plants
Most hydropower plants are conventional in design, meaning they use
one-way water flow to generate electricity. There are two categories of
conventional plants, run-of-river and storage plants.
Run-of-river plants—These plants use little, if any, stored water
to provide water flow through the turbines. Although some plants store a day
or week's worth of water, weather changes—especially seasonal changes—cause
run-of-river plants to experience significant fluctuations in power output.
Storage plants—These plants have enough storage capacity to
off-set seasonal fluctuations in water flow and provide a constant supply of
electricity throughout the year. Large dams can store several years worth of
In contrast to conventional hydropower plants, pumped storage plants
reuse water. After water initially produces electricity, it flows from the
turbines into a lower reservoir located below the dam. During off-peak hours
(periods of low energy demand), some of the water is pumped into an upper
reservoir and reused during periods of peak-demand.
Building Hydropower Plants
Most hydropower plants are built through federal or local agencies as part
of a multipurpose project. In addition to generating electricity, dams and
reservoirs provide flood control, water supply, irrigation, transportation,
recreation and refuges for fish and birds. Private utilities also build
hydropower plants, although not as many as government agencies.
Hydropower is a clean, domestic and renewable source of energy. Hydropower
plants provide inexpensive electricity and produce no pollution. And, unlike
other energy sources such as fossil fuels, water is not destroyed during the
production of electricity—it can be reused for other purposes.
Hydropower plants can significantly impact the surrounding area—reservoirs
can cover towns, scenic locations and farmland, as well as affect fish and
wildlife habitat. To mitigate impact on migration patterns and wildlife
habitats, dams maintain a steady stream flow and can be designed or
retrofitted with fish ladders and fishways to help fish migrate upstream to
The best sites for hydroelectric plants are swift-flowing rivers or steams,
mountainous regions and areas with heavy rainfall. Only 20 percent of
potential U.S. hydro-power has been developed, but unfavorable terrain and
environmental concerns make many sites unsuitable for hydropower plants.
However, since only 2,400 of the nation's 80,000 dams are currently used
for hydropower, new projects do not necessarily require building new
dams—many existing dams can be retrofitted to produce electricity. At
existing hydropower plants, advanced technologies can be installed to
increase efficiently and energy production. (http://www.nrel.gov/applying_technologies/climate_neutral/pdfs/hydro_characture.pdf)
Campo Nuevo Watermotor is the only
modern turbine designed to drive common machines directly with waterpower.
It converts waterpower directly into mechanical power at a highly efficient
The Watermotor has a patented switch that allows
instant on/off power control. This unique feature makes it practical and
safe to run machines directly with waterpower. The combination of high
efficiency and power control makes it possible to use much smaller
waterpower sources than ever before.
Although water-power has been in use for thousands of years, with the
Watermotor small scale waterpower has become a vast new natural energy
Most of the common machines used in workshops, industry, and farms are
driven by motors of only .5 - 5 horsepower. The Watermotor will produce this
amount of power at an extremely low cost and with a minimum of ecological
Micro-Hydro Power Plant overview & basic
math formulas & conversion needed to find "Head", "PSI", Flow Losses" &
A basic explanation of how an electric
motor may be used as a generator. Also includes safety precautions
for and the reasons they are needed.
A large table containing pipe flow losses
for Sch 40 steel & PVC pipe with diameters from 3/4" to 42" & flow fates
to 56,000 GPM ( 7486 CFS)
Weirs and several other methods for
measuring water flow from small streams to rivers. Diagrams &
specs. included for weirs as well as weir charts.
Several Tables detailing various
mechanical properties of various pipe types (PVC, Steel & Others)
A basic outline of why a Governor or Load
Control is needed for Asynchronous (Real) Generators, as well as some AC
theory within the context of line frequency & high & low voltage
Most of the basic Turbine types are on
this page with photos and their theory of operation. Several
"Older" turbine types will also be found here
"The Banki Water Turbine", Oregon State
University, Civil Engineering ,Department Engineering Bulletin Number 25
By C. A. Mockmore and Fred Mayfield. Originally published
in 1949. Details the theory of operation of the crossflow turbine.
Very math intensive.
Various "home-brew"' method for machine
work need for the Banki Crossflow Turbine.
Basic aspects of waterhammer. What it is,
how to control / prevent it as well the math to find peak excess
A look into the past. A variety of
waterwheel types with photos.
Various "Hardcopy" publications I used as
research for this web site as well as internet links relative to hydro
By Joe Cole
Micro Hydro Systems work?
Hydro power is an old established method of energy production.
Water is captured via a filter / intake structure and passes downhill in a
pipeline to the turbine. The water exits the pipe under pressure through a
nozzle and strikes a water wheel (runner). The force of which spins the
runner which is direct coupled to an electricity generating permanent magnet
alternator or enhanced performance induction generator. The electricity is
then electronically regulated and transmitted via cable for use. http://www.platypuspower.com.au/
People living in remote locations are often denied the
benefits of electricity. Diesel, kerosene, batteries and
firewood only supply certain energy needs. These are often
difficult to transport, require ongoing expense and ultimately
damage the local environment. PowerPal micro-hydroelectric
generators provide an effective alternative. Many isolated
settlements are located next to permanent streams that can be
used to harness the power of micro-hydro electricity 24 hours a
day. Until now, cost and reliability have been major issues.
Powerpal has successfully addressed these issues. http://www.powerpal.com/
Micro-Hydro List -
Egroups - This discussion group focuses on technical and non-technical aspects
of run-of-river micro hydropower schemes.
The definition of micro hydropower varies
in different countries and can even included systems with a capacity of
a few megawatts. One of the many definitions for micro hydropower is:
hydro systems up till a rated capacity of approximately 300 kW capacity.
The limit is set to 300 kW because this is about the maximum size for
most stand alone hydro systems not connected to the grid, and suitable
for "run-of-the-river" installations.
The Micro Hydro
Centre has been carrying out research into low-cost equipment for
small-scale hydro-electric power (up to 100kW) since 1985. The main
motivation for this research is to develop and disseminate standardised
hydro generator units that are directly affordable by villagers in
developing countries, financially viable, through fuel savings and
income generation, and suitable for local manufacture and use in adverse
conditions. In addition to research and development the Micro Hydro
Centre is involved in information dissemination, training and technology
Micro-hydro is a proven cost effective renewable energy system. If you
have access to a reliable flow of water, it should be an option you
consider. The energy of running water is harnessed by a turbine and
converted to electricity.
The amount of energy you produce depends on water pressure (measured
in terms of "head"or the vertical distance from the water
take-off point down to the turbine), and volume, (measured as
"flow" in litres per second.) Heads as low as 5 meters and
flows of 1 litre per second will produce power. Low head systems require
large water flows, and low flow systems require a high head. http://www.power-options.co.nz/hydro.html
Independent Power & Light supplies photovoltaic(PV) panels, small
hydropower turbines (microhydro), wind generators, inverters, batteries,
power control panels, meters and other materials required to put
together a complete off-grid power system along with expertise in
design, installation and adapting the system to the individual site and
or mini–micro hydro power is one of the earliest known renewable
energy sources, in existence in the country since the beginning of the
20th century. In fact much before that, the technology was used in
Himalayan villages in the form of waterwheels to provide motive power to
run devices like grinders. References to mechanical energy extraction
have been found from as early as twelfth century. http://www.anzwers.net/free/wnr/hydpower.htm
From falls of water as low as 3 feet with flows as small as 12 GPM,
hydro systems can take your creek, spring, pond, river, or runoff water
and turn it into clean, efficient electricity. This can put a lid on
rising power bills or create a completely independent power system at
the lowest cost. In areas with high rainfalls in the winter and sunny
summers, hydro combines naturally with solar electricity for year-round
Over twenty two years
experience in micro hydro, utility grade
turbine designs and modern production techniques, have all
combined to bring the first ultra-low head micro turbine
renewable energy market. http://www.waterturbine.com/
An Easy to Build and Operate
Induction Generator http://www.qsl.net/ns8o/Induction_Generator.html
Motors as Generators for
by Nigel Smith
$13.95 (includes USA shipping), 1997, 82 pages.
Nigel Smith shows you how to convert ordinary induction motors for use
in micro-hydro applications. Covers topics such as motor selection,
efficiency, advantages and disadvantages of induction motors vs. other
types of generator, capacitor requirements, voltage and frequency, load
considerations, conversion of 3 phase to 1 phase, motor startup, and
more! Covers both theory and practice of using commonly available
induction motors for DIY micro-hydro applications. If you have a stream
and want to build your own micro-hydro plant, you must check this out. Order
it now from PicoTurbine.com!
US Army Corp of Engineers manuals sometime provide
background information and can be useful They have
numerous manuals of dams and river hydraulics.
Planning for Sustainable Agriculture
Keyline is a set of principles, techniques and systems, which form the
logical basis for a practical plan for the sustainable development of
rural and urban landscapes.
The first book on Keyline book was published in 1954. In it, P.A.
Yeomans exploded the myth that it takes 1,000 years to produce an inch
of topsoil. Yeomans pioneered, among other things, the use of on farm
irrigation dams in Australian, as well as chisel plows and subsoil
aerating rippers. Yeomans perfected a system of amplified contour
ripping that controlled rainfall run off and enabled the fast flood
irrigation of undulating land with out the need for land terracing. http://www.keyline.com.au/
on environmental issues, green politics, alternative
technologies, renewable energy, organic gardening and
farming, and ecological