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Hydroelectric Power - Water power - micro hydro systems
Micro 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 <belisleb@webnet.qc.ca> of Electrovent
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. http://www.ata.org.au/~ata/basics/bashydro.htm
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 U.S.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 electricity produced.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
ConventionalMost 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 water.
Pumped Storage
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.
Benefits
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.
Obstacles
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 spawn.
Potential
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/lab/pao/hydroelectric.html)
Micro-Hydro Power Plant overview & basic math formulas & conversion needed to find "Head", "PSI", Flow Losses" & Power Output.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 conditions.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 pressure.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 power/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.netc.net.au/platypus/Info:
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.
Pinecrest Hydro - Many land owners look wishfully at the creek that flows through their property. They dream of tapping the power of the water, but they are not blessed with a waterfall or with any way to develop a head of ten to twenty feet. (The head is the vertical drop of the water.) All they have is a high volume creek flowing through relatively flat land. I designed this system to illustrate the feasibility of using an ultra low head hydroelectric system to provide "usable amounts" of electric power. This system is designed to be located in the creek bed using a small dam to provide a minimum head. The prototype micro-hydroelectric system operates on a head of about 2.75 feet!
http://www.geocities.com/wim_klunne/hydro/index.html 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.http://www.ecn.nl/unit_de/ide/
http://www.geocities.com/wim_klunne
http://come.to/microhydrohttp://members.tripod.com/nxtwave/gaiatech/index.html To make a pulser pump, you need a good flow of water. If your stream is a foot deep (30 cm), 2 yards wide, (or 2 meters wide) and flowing at walking pace, then its plenty big enough. You need somewhere where the water falls (or can fall) about 2 feet 60 cm (about knee high will do). At that place, you can make a pulser pump beside the stream (and a fish ladder in the stream). It can be made using 15 cm diameter plastic pipes and 2.5 cm diameter plastic pipes and pipe fittings to connect them. 8 or 9 meters of 15 cm pipe is required and about 7 m of 2.5 cm pipe. A hole 4 m to 5 m deep, at least 1 m wide and at least 3 m long is required.
Our current focus is on the development and implementation of very efficient water pumping technologies that would be useful in agricultural and business applications in both industrialized countries and third world countries around the globe. Not only is this emerging technology efficient it is also cost effective. This water pumping technology is being developed in a manner that would allow local communities to manufacture this efficient water pump in their own communities by their own cottage industries with local materials. http://www.thepump.org/howpumpworks.html
The following information is provided to help you consider small to mid-sized hydroelectric generators that are designed to be 12, 24, or 48 volt battery chargers. A stream or creek is needed - they operate with a relatively small volume of water. They charge batteries 24 hours per day, and the power can be drawn from the battery. As little as 100 gallons per minute (GPM) falling only 10 feet through a pipe, or 5 gallons per minute falling 200 feet through a pipe can supply enough power to run a small household. http://www.poweriseverything.com/impt-info/hydropwrpage.html
Micro-hyrdo power was one of the earliest of the small scale renewable energy technologies to be developed, and is still an important source of energy today. This short course provides a basic understanding of resource assessment, conversion technology and evaluation of costs and benefits to end users. The fees for the course are given below. http://www.reading.ac.uk/AcaDepts/st/home/energygp/short/micro.html
- micro hydro
- It appears that, for a small initial outlay (about $1,000), a micro-hydro system could be set up which will generate sufficient power to run two or more houses. It may be more efficient to have one large setup, or it may be more efficient to distribute the load. In any case, we will need a site which is fairly damp and has constant running water, but that's okay, because thats exactly the sort of place we'd like to live in anyways. http://www.gii.net/dwayne/HTML/Community/hydro.html
- micro hydro suppliers
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 transfer. http://www.eee.ntu.ac.uk/research/microhydro/index.html
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 requirements. http://www.independent-power.com/
Small 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 independence. http://www.jade-mtn.com/hydro.html
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 to the
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 Micro-Hydro Power
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 good
background information and can be useful They have numerous manuals of dams and river hydraulics.http://www.usace.army.mil/inet/usace-docs/eng-manuals/em.htm
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/
Dealers:
http://www.backwoodssolar.com/
Maya Books
Publications on environmental issues, green politics, alternative technologies, renewable energy, organic gardening and farming, and ecological building. http://www.mayabooks.ndirect.co.uk/renewable.html
