Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Micro Hydro shopping experience:
1. Compare - without doubt the biggest advantage that the Micro Hydro offers shoppers today is the ability to compare thousands of Micro Hydro at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Micro Hydro? Wrong! If the Micro Hydro is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Micro Hydro then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Micro Hydro? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Micro Hydro and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Micro Hydro wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Micro Hydro then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Micro Hydro site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Micro Hydro, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Micro Hydro, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
Micro Hydro is a term used for
hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a Remote Area Power Supply (RAPS). There are many of these installations around the world, including several delivering around 50 kW in the
Solomon Islands, supplying energy for small communities.
Micro hydro is frequently accomplished with a pelton wheel for high head, low flow water supply. The installation is often just a small dam pool, at the top of a waterfall, with several hundred feet of pipe leading to a small generator housing.
In low-head installations, maintenance and mechanism costs often become important. A low-head system moves larger amounts of water, and is more likely to encounter surface debris. For this reason a
Banki turbine, a pressurized self-cleaning crossflow waterwheel, is often preferred for low-head microhydropower systems. Though less efficient, its simpler structure is less expensive than other low-head turbines of the same capacity. Since the water flows in, then out of it, it cleans itself and is less prone to jam with debris.
Micro hydro systems complement
photovoltaics solar energy systems because in many areas, water flow, and thus available hydro power, is highest in the winter when solar energy is at a minimum.
Frequency stability
The frequency of the alternating current generated needs to match the local standard
utility frequency. Typically, the controller valves the water supply to generate a constant frequency for motors and clocks. The normal controller is a small programmable logic controller with a custom program that uses a deadband to minimize valve motion so the valve wears out as slowly as possible, while conserving water.
A grid-linked system slaves its generator to the grid by measuring current, to assure that the power is always output, so the grid never drives the turbine. The usual scheme is to measure voltage across a shunt resistor on one of the phases. The external utility's grid controller provides precision frequency controls.
An independent system usually governs its long-term frequency from an externally-broadcast time-standard. The hydropower's AC time may vary by several seconds per hour, but over many days, it varies not at all. Traditionally a caretaker would compare a simple AC clock driven by the hydropower system to a short-wave clock broadcast and adjust the mechanical governor on the hydropower system until the AC clock read the same as the broadcast for a few minutes. Over time, the result would be good. With a modern PLC-based system, the care-taker can just set the PLC's clock periodically from a radio clock, say once per week. Some more-professional systems automatically set the controller's clock from a radio clock.
See also
External links
- Portal on microhydro power
- Informational articles at Energy Systems & Design
- Some notes on microhdyro classifications and equations
- Cheap energy hope from waterwheel BBC news story.
- Micro Hydro information Dorado Vista ranch application
- European Small Hydropower Association
- Idaho National Engineering Laboratory Hydropower Prospector
Micro Hydro is a term used for hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a Remote Area Power Supply (RAPS). There are many of these installations around the world, including several delivering around 50 kW in the Solomon Islands, supplying energy for small communities.
Micro hydro is frequently accomplished with a pelton wheel for high head, low flow water supply. The installation is often just a small dam pool, at the top of a waterfall, with several hundred feet of pipe leading to a small generator housing.
In low-head installations, maintenance and mechanism costs often become important. A low-head system moves larger amounts of water, and is more likely to encounter surface debris. For this reason a
Banki turbine, a pressurized self-cleaning crossflow waterwheel, is often preferred for low-head microhydropower systems. Though less efficient, its simpler structure is less expensive than other low-head turbines of the same capacity. Since the water flows in, then out of it, it cleans itself and is less prone to jam with debris.
Micro hydro systems complement
photovoltaics solar energy systems because in many areas, water flow, and thus available hydro power, is highest in the winter when solar energy is at a minimum.
Frequency stability
The frequency of the
alternating current generated needs to match the local standard
utility frequency. Typically, the controller valves the water supply to generate a constant frequency for motors and clocks. The normal controller is a small programmable logic controller with a custom program that uses a deadband to minimize valve motion so the valve wears out as slowly as possible, while conserving water.
A grid-linked system slaves its generator to the grid by measuring current, to assure that the power is always output, so the grid never drives the turbine. The usual scheme is to measure voltage across a shunt resistor on one of the phases. The external utility's grid controller provides precision frequency controls.
An independent system usually governs its long-term frequency from an externally-broadcast time-standard. The hydropower's AC time may vary by several seconds per hour, but over many days, it varies not at all. Traditionally a caretaker would compare a simple AC clock driven by the hydropower system to a short-wave clock broadcast and adjust the mechanical governor on the hydropower system until the AC clock read the same as the broadcast for a few minutes. Over time, the result would be good. With a modern PLC-based system, the care-taker can just set the PLC's clock periodically from a radio clock, say once per week. Some more-professional systems automatically set the controller's clock from a radio clock.
See also
External links
- Portal on microhydro power
- Informational articles at Energy Systems & Design
- Some notes on microhdyro classifications and equations
- Cheap energy hope from waterwheel BBC news story.
- Micro Hydro information Dorado Vista ranch application
- European Small Hydropower Association
- Idaho National Engineering Laboratory Hydropower Prospector
