The objective of hydro power generation is to transform the potential energy of flowing water into electrical energy by driving a turbine and generator. This concept is universal throughout all types of hydro power generation. The precise capacity and definition of small scale hydro can vary across different countries, therefore our study will consider generation below 5MW to be small scale.
The amount of power generated by a scheme is directly proportional to the volume of water passing through the turbine and the height difference between the turbine and the scheme intake. The difference in height between intake and turbine is commonly referred to as the “head”.
In general, schemes can be characterised whether they are high, medium or low head configurations and are classified as:
- High head: Above 100m
- Medium head: 30m -100m
- Low head: 2m-30m
Hydro schemes that have minimal storage capacity, i.e. no reservoir, rely heavily on the instantaneous flow rate of the river to provide sufficient water.
As the economics and performance of a common pressure header system are found to be highly dependent on the geographical layout of the scheme, it proved beyond the scope of the project to develop a method that would model this for all general conditions. It was decided therefore that it would be of more benefit to accurately model the economics and performance of individual systems and, through accurate and thorough assumptions, the effect of joining them in a combined pressure header configuration. This section details the methods and calculations that are of significance to this process.
This section will cover: