A few lucky souls out there enjoy the luxury of living close enough to a water source that they can make use of micro hydro power. You might actually fall into this category without even realizing it.
Micro Hydropower Systems Definition
Any power generation system on a small scale is known as “micro hydro”. These systems are typically used to provide power to small villages or individual home owners. It’s been said that systems that generate less than 100 kilowatts of electricity fall into this category.
Components of a Microhydro System
There are three main components of this type of a power generation system. The first is a steady source of water, the second is a micro hydro turbine, and the third is a way to control the rate at which the water spins the turbine.
Types of Water Sources
The water source for this type of a system can vary quite a bit. Everything from swift moving rivers to ponds can be used effectively. The primary thing that is necessary is for the source of water to be moving in some way. With a fast moving stream or river, the flow of the waterway can be harnessed directly to turn a microhydro turbine.
In applications where the water doesn’t naturally flow at a fast enough rate to power a turbine something needs to be done to create a flow of water. This may mean running a long pipe from a water source at one elevation to a turbine at a lower elevation. It may also mean building a small dam to cause water to back up so that it can flow over a man made waterfall. There are many ways to accomplish this but the goal is the same and that is to manipulate a water source in some way to create a flow of water that can be used to power the turbine.
Some terms to understand about micro hydro turbines are “head” and “flow”. Head is the difference in elevation between the water source and the turbine. Flow or flow rate is the speed at which the water is traveling. As a general rule, low head micro hydro systems have water that falls a distance of 16 meters or less.
Controlling The Flow Of Water
Depending upon the type of generator that is being driven with the micro hydro turbine, the voltage could vary with changes in the flow of water. This happens because differences in the rates of flowing water could cause the turbine to spin at different speeds. Slower speeds would mean lower voltages and higher speeds would mean higher voltages. To regulate this, some kind of a controller or regulator is needed. This is commonly an adjustable valve that automatically adjusts to control the flow of water entering the turbine.
Alternately, a special generator that only produces electricity when the turbine is spinning at a certain rate can be installed. This type of generator is sort of an “all or nothing” type of a system. If the flows aren’t high enough to spin the generator fast enough to generate the precise voltage of power, the generator doesn’t output any power at all. If the flows are faster than what is needed, the voltage doesn’t increase with this type of a system, it remains constant.
Your Water Source May Actually Be Quiet Suitable
Don’t think that because you don’t have a huge reservoir or a raging river in your back yard that you can’t make use of a micro hydro power system. There are many ways to make use of existing water sources. For example, if you have a small stream or pond at a high spot on your property you can construct a long pipe that gradually slopes to a lower area of your property. In this case the weight of the water that is built up in the pipe from the difference in elevation will create a lot of pressure. This pressure can be increased even more with the use of a nozzle. If you direct this high pressure water though a nozzle and into a micro hydro turbine, it will often be more than adequate to spin the turbine at sufficient speeds to generate electricity.
If you have a raging current of water in your backyard river, you can likely install a home hydro power system that will actually produce 120V AC power that you can wire right into your home. You may even be able to tie into the grid and sell your excess power back to the power company. Most people, however, won’t have the right conditions for this but that doesn’t mean they still can’t benefit by installing a small scale hydro power system. In this case, a smaller turbine that puts out DC electricity could be used to charge a bank of batteries.
The bottom line is that you should realize that with a little bit of ingenuity, there’s a pretty good chance that your water source could be harnessed as a source of clean, renewable energy for your home.