Selecting the Right System
Choosing the right type of micro hydropower system for your site depends on its unique physical characteristics and conditions.
As water flows downstream, its gravitational energy can be converted into electric power by a hydroelectric system. Many smaller rivers and streams are capable of providing micro-hydro power for local use and to be fed into the power system grid. While different sites will have unique systems that are best here are several common components that make up a micro hydropower system. Other systems may not have a penstock, instead having the intake feed directly into the powerhouse, including the turbine, located alongside or as part of the dam.
Intake: A structure that diverts water from a natural waterway into the turbine
Canal: A structure that moves water from natural waterway to the forebay
Forebay: Impoundment or reservoir immediately above a dam or intake structure at a hydropower plant
Impoundment: Body of water created by a structure that obstructs flow, such as a dam
Penstock: A closed conduit or pipe for conducting water from the forebay to turbines in the powerhouse.
Powerhouse: The structure that houses generators and turbines at a hydropower facility
Turbine: A machine that produces continuous power in which a wheel or rotor revolves by a fast-moving flow of water.
Image from DOE’s Office of Energy Efficiency and Renewable Energy.
Site Restrictions & Considerations
Water Use Restrictions
There may be laws that restrict the amount of water that can be diverted from a stream, either permanently or temporarily, requiring a system to limit water input.
Many streams support fish and other wildlife whose habitat could be affected by the installation of a micro-hydro system.
Site Survey Checklist
Before getting started on technology selection, it’s important to understand your site. Use this checklist to make sure you understand the characteristics of your site and it’s potential for microhydro. While understanding environmental impacts of microhydro is a priority, it is also critical to make sure your site is suitable for a microhydro system before moving further along in the process.
- Environmental Impacts
- Measure head
- Measure site flow
- Calculate estimated power
If your site is suitable, the next steps include following local, state, and federal regulatory requirements, as well as determining how you will finance the installation and ongoing maintenance of the system.