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centraL HIDROELECTRICA casera y economica

Central hidroeléctrica casera y económica

10 comentariosmanzanaPor manzana El 29 de agosto de 2011
Navegando me encontré con este curioso diseño de turbina hidráulica hecha por muy bajo costo y de forma muy sencilla. Sam Redfield es el responsable de este brillante diseño donde con un cubo de plástico de unos 20l podría servir uno de pintura por ejemplo, y unas tuberías de PVC junto con un  alternador de imanes permanentes como generador eléctrico obtiene este pequeña fuente de energía limpia.
pico hydro 4 Central hidroeléctrica casera y económica
pico hydro Central hidroeléctrica casera y económica
Turbina funcionando en Guatemala.
Al generador se le instala un regulador de voltaje, una batería de automóvil y un inversor. La batería almacena la energía, el regulador controla el voltaje e impide la sobrecarga de la batería y el inversor transforma la corriente directa en alterna. Según el inventor se puede generar 60 Watts, capaz de cargar 10 teléfonos móviles al mismo tiempo sin que se reduzca la carga de la batería.
turbina pelton de pvc Central hidroeléctrica casera y económica
La turbina construida con codos de PVC
turbina pico hidro Central hidroeléctrica casera y económica
Detalle del interior donde se ve la correcta disposición para que funcione el sistema.
No es mucha energía, no obstante, es necesario considerar que este generador al contrario que otras alternativas como la eólica o solar dispone de su fuente de poder las 24 horas del día y en general, sin interrupciones y otra posibilidad es instalar varios generadores y cargar un sistema de baterías en serie con lo que se podría ampliar la potencia.
El costo entero del sistema es de unos 350 euros, la mayor parte por el motor, se podría convertir un alternador de coche, o utilizar un dinamo o hasta construir el motor en si, claro que seguramente no se lograría la misma potencia, eso si el costo seria mucho menor.
alternador pico hydro Central hidroeléctrica casera y económica
Alternador colocado en su sitio.
Este tipo de sistemas hidroeléctricos que generan menos de 1 kW (1000 vatios) son conocidos como pico-hydro (en inglés) o pico-hidroenergía. Permiten producir energía eléctrica aprovechando pequeños riachuelos con caídas de agua como fuente energía. Algo muy bueno para las comunidades rurales que se encuentran cerca a estos riachuelos, ya que habitualmente no tienen acceso a la electricidad, de tal forma que este tipo de pico-turbinas de bajo costo ofrecen una excelente oportunidad para proveer electricidad.
turbina pico hidraulica Central hidroeléctrica casera y económica
Sam Redfield con la turbina ya montada y funcionando en Guatemala.
Para mas información y la lista completa de materiales necesarios para construir este generador hidráulico en la pagina de AIDG(Appropiate Infrastructure Development Group).
Te gusto, ayúdanos y compártelo:



Work continues. One of the issues that we face in deploying the system is cost. The Permanent Magnet Alternator that generates the electricity in the system costs more than $300.00 US and has to be imported from the States. As part of my program with AIDG in Guatemala, I investigated the possibility of rebuilding a Toyota alternator to function as a Permanent Magnet Alternator. After investigating several possibilities, I am happy to report that we now have a working prototype, which is being integrated into the system. Other improvements include integrating the voltage regulator into the device and improvements in turbine performance. In the coming months trials will continue and no doubt improvements in economy and performance will be made. My work with AIDG Guatemala was invaluable to me in understanding the energy issues people face in the developing world and provided me an excellent opportunity to develop my technology in an environment that fosters innovation in a setting where people’s lives are positively effected. Thanks AIDG!




Tech Update: Pico-hydro system developments

Sam Redfield, Project Manager of AIDG’s pico-hydro program in Guatemala was just accepted for MIT’s International Development Design Summit in Ghana this summer! Here is an account of some of his work at our new facility in Guatemala. Keep an eye out for the build manual he is producing for the Five Gallon Bucket Generator!
Sam Redfield
Hi everyone. I’m back in Xela, home of AIDG’s offices and research facility in Central America. Big things are happening down here. This January we moved into a beautiful new compound. Rising above the neighboring buildings, the new office resembles a pagoda. Its red corrugated roof flanking three stories of golden clapboard walls is something of an enigma in a neighborhood dominated by low concrete block houses. In addition to much needed additional office space, we now have a new fabrication shop, electronics and water lab and, under construction, housing to accommodate several interns and visiting researchers. The new office is full of light and the staff and interns that work here are noticeably happier with the new work space. In what can be chilly mornings in a city perched at roughly 7000 ft., it’s nice to work in a place where the brilliant morning sun comes in through the windows and warms the space.
New AIDG Compound
I have returned to Xela to continue my work on the pico-hydro system that I field tested in La Florida last year. Pico-hydro systems are small hydroelectric generators that produce less than one kilowatt of power. We are looking at using the generator to provide basic lighting, cell phone charging and ultra violet water purification in under served communities. Housed in a five gallon bucket, and employing a modified car alternator driven by a turbine, the generator promises the potential of cheap clean energy to those without access to the electricity grid.
Pico-hydro test in La Florida in 2008
Pico-hydro test in La Florida in 2008

The Permanent Magnet Alternator

Last year, we established that the generator was viable as a single point power source that could be installed quickly with limited resources and could produce consistent power with modest water usage. Still unresolved were issues of cost, longevity of service and overall performance for electrical output. The generator was built using a rather expensive modified GM alternator produced in the States for the home brew wind turbine market. This modified alternator, called a permanent magnet alternator (PMA) produces energy at low RPM’s and works well in small-scale hydroelectric systems. In addition to the price, (more that $300.00 U.S.), the alternator would have to be shipped to its destination country, adding additional cost. The PMA was by far the generator’s most expensive component and the only element in the system that would need to be imported, so we looked to it to reduce the generator’s overall cost.
My solution was to modify the Nippo Denso alternator produced for Toyota’s 22R engine. They key was using low-tech mods that could be cheaply and easily reproduced in a basic machine shop. The Nippo Denso alternator, found in most Toyota pickup trucks and many sedans in developing countries, might just be the most common alternator in the world. They are often shipped to developing countries to be rebuilt for the market in the US and other developed countries. Where in the States these alternators are simply replaced with rebuilt alternators when they fail, in developing countries there is extensive infrastructure to rebuild them. They are available in quantity in Guatemala and are cheap.
My design for the Toyota based PMA uses only the alternator casing and the stator (the wire coils that surround the rotor inside the alternator). For the conversion, the rotor is completely rebuilt with powerful neodymium magnets and the stator is rewound with thinner gage wire. Non-functioning Toyota alternators can be had for about $20.00 US in Guatemala if bought in bulk. The magnets are the only part of the new alternator that may need to be imported.
Left: rebuilt rotor with permanent magnets. Right: Toyota rotor.
Left: Rebuilt permanent magnet rotor. Right: Toyota rotor.
Toyota based permanent magnet alternator
Toyota based permanent magnet alternator

Our new hydro test bench

Last year we lacked the facilities to do extensive testing of the PMA and could only determine that, yes, it worked and that it produced energy at low RPM’s. But we couldn’t determine which gauge windings of the stator would produce the most power given the bucket generator’s RPM ranges. We needed more controlled study conditions, particularly as field tests were difficult to repeat (distance to test site, variability of water flow, etc.).
This past month, we set up both a hydro and a PMA test bench. The hydro test bench simulates the head and water flow rate that determine the output of a small hydroelectric system. By varying the head and flow in the test bench, we can simulate the various conditions under which the bucket generator operates and rate its performance under different loads.
Bucket generator connected to hydro test bench
Bucket generator connected to hydro test bench
We can’t directly measure the RPMs of the bucket generator when it is hooked up to the hydro test bench, but we can estimate this number using the PMA test bench. Simply put, we find the number of RPMs in the PMA test bench that replicates the current produced by our bucket generator in the hydro test bench, and thereby get an estimate of the bucket generator RPMs. Using the PMA test bench we can only investigate which windings offer us the highest current at the appropriate RPMs for the system.
PMA test bench
PMA test bench
Direct comparison of the GM and Toyota PMAs is difficult due to differences in configuration, size and layout of the 2 systems. That said we were able to determine that the Toyota PMA offers performance in the same general range of the GM system and at a fraction of the cost. If manufactured in bulk, the Toyota PMA would come in at around $120.00 U.S. and the entire bucket generator could cost about $160.00 U.S.
Currently, we are trying to determine which wind of the Toyota PMA will give us the maximum current at the RPM ranges of the bucket generator system. At our maximum available head on the test bench, about 90’, we were able to produce over 1,200 RPMs and 90 watts. We expect to get more than 100 watts in the field at slightly higher heads. We don’t know yet what the maximum output will be.
This spring, we’ll be installing at least two of the bucket generators in Haiti to power ultra violet water purification equipment. A portion of the funding for this project was generously provided by St Peter’s Church in Weston. AIDG’s Haiti office is partnering with local NGOs, including our good friends at SOIL, to address the lack of clean potable water in their service areas. Each ultra violet purification device draws about 30 watts. With the generator, we expect to be able to power three or more UV devices at 100’ of head and 50 gallons a minute of flow. Currently, sites surveys are being conducted in Haiti to determine head and flow conditions and find suitable sites that provide year round consistent water. These long term test sites will provide data on performance as well as service and maintenance needs of the system.
Sam Redfield
AIDG
Quetzaltenango, Guatemala
Related posts:
Sam Redfield on Pico-hydro at La Florida
Parts List for Five Gallon Bucket Hydroelectric Generator
ddress will not be published. Required fields are marked *
https://www.engineeringforchange.org/static/content/Energy/S00070/5%20Gallon%20Bucket%20Build%20Manual.pdf