Micro Hydro Electric Power Plant is usually classified as a hydro electric power plant that can produce up to 100 kW of power. They are usually used to supply energy to small off-grid communities that have a natural water source close to it that never runs out.
First, let me get to the most important part of this post right away. For me, the easiest way to build a micro hydro electric power plant if you have no experience what so ever and don’t come from an engineering background, is to enlist the aide of engineering students.
I’ve known of a couple of mechanical and electrical engineering students who designed and built a hydro electric dam for a community for their thesis. One can easily approach the faculty of an engineering school at the start of the school year and ask if they have students willing to take up building a micro hydro electric power plant. This way you can save on engineering expertise and maybe some of the cost if the students or school are willing to shoulder some of it.
If the electricity is to be used by off grid communities, then you could also enlist the aide of NGO’s or Electric Companies who have social arms specific to bringing electricity to rural communities via renewable energy means.
If that’s all you needed to know then you can skip this article already because the remaining parts could get technical.
Compared to most renewable energy technologies, Hydro electric generators can operate for 24 hours and isn’t entirely dependent nor affected by the weather (unless its a drought). Care must be taken however to check if there are regulations barring the use of micro hydro in your area or if permits are required to install one.
From a simple body of water, one can easily tap it for electricity as long as the water source has either elevation or is flowing. It is crucial to determine early on if the flow and head of the water source is adequate enough to harvest energy from.
Water taken from the top of a water fall or an elevated body of water can be classified as high head/low flow. Examples of low head/high flow water sources are irrigation ditches, running rivers and streams.
Flow is defined as the speed with which a volume of water flows and is usually measured as ft3/sec or m3/sec. Head is defined as the pressure exerted by the fluid and is usually obtained by the distance of the surface of the water source to the input to the turbine. Head is usually measured in ft or m.
Components of a Modern Micro Hydro Electric System:
- Turbine - is responsible for converting the motion of the water to rotational energy. The type of turbine to be used will depend greatly on the type of water source to be harnessed. If it is of high head/low flow, typically a pelton wheel type turbine is used. If it is of low head/high flow.
- DC generator - converts the mechanical rotation of the turbine into direct current electricity.
- Inverter - converts the DC electricity into AC electricity. There are some cases where a generator which produces AC electricity is already used.
- Electronic Load Controller - is the most important addition to the micro hydro design that simplifies greatly the creation of a steady flow of electricity. The Load controller has made it possible to automatically regulate the electricity generated, even when the speed of the flowing fluid varies.
Below are some videos from Youtube showing some practical applications of micro hydro projects.
Micro Hydro from Old Generator Parts
Columbia University Micro Hydro Project
Micro Hydro Peru
Micro Hydro Project Indonesia
Micro hydro project in Thailand
India Micro Hydro project from scrap materials and in an irrigation channel
Indian Thesis Project
Kenya Hydro Electric