Micro-Hydro Systems

1. Description of the Technology
2. State of the Industry
3. Is a Micro-Hydro System Right for Me?
4. Basic Numbers
5. Benefits, Drawbacks and Possible Pitfalls
6. Planning Issues and Regulations
7. Setting Up and Operating a Micro-Hydro System
8. Additional Resources

Description of the Technology

Hydropower uses turbines to convert the energy of flowing water into electricity. Micro-hydro systems generate less than 100 kW and are usually "run of the river" operations that don't involve large dams or water storage reservoirs, so they generally create very little impact on the local ecosystem.

A simple micro-hydro system consists of:

1. An intake or weir that diverts water from the stream or river
2. A pipeline or canal that carries the water to the turbine
3. A trash rack that filters out debris before water enters the turbine
4. A turbine (usually enclosed in a powerhouse) that converts the mechanical energy of falling water into electrical energy
5. A tailrace that brings the water back to the river or stream
6. Transmission lines that carry the electricity to its destination

State of the Industry

Waterpower has been used for centuries to grind grains and, more recently, to generate electricity. Currently it is a major source of energy in Ontario, but much of this comes from big projects.

That still leaves thousands of megawatts of untapped potential, however: there are thousands of rivers and streams in the province that could be used to generate electricity.

Is a Micro-Hydro System Right for Me?

Clearly, the first requirement is to have a suitable stream or river on your property. The amount of energy you can capture depends on the flow rate (how much water flows per second) and the head (the vertical distance it falls). You'll need at least a year's worth of data on water flow to decide if it's worth installing a system at a particular site.

Depending on your needs and physical set-up, you can choose to install a stand-alone system or connect to the power grid. In either case, you'll need transmission lines to deliver the electricity to its destination.

Basic Numbers

According to the Integration of Renewable Energy on Farms website, a low or ultra-low head system costs $2,000-9,000 per kilowatt, installed. Most turbines have a life expectancy of at least 25 years.

Benefits, Drawbacks and Possible Pitfalls

Benefits:

• Reliable, proven technology
• Low operating and maintenance costs
• No emissions

Drawbacks:

• Water flow can be affected by seasonal changes and climate fluctuations
• Micro-hydro systems require regular maintenance: making sure the intake is not clogged, clearing out silt, checking for leaks, greasing machinery, tightening belts, etc.

Possible pitfalls:

• Waterpower systems may not be permitted on certain streams and rivers

Planning Issues and Regulations

Before you get started, you'll need a water license, land-use approval and other local permits.

Apply to the Ministry of Natural Resources for a site release, and contact both your municipality and your local conservation authority for approvals and permits.

Your project will also need to undergo an environmental screening process, and it must comply with required electrical codes, building regulations and site regulations.

Finally, if you plan to connect your system to the power grid, there are additional requirements you'll need to meet.

Setting Up and Operating a Micro-Hydro System

If you opt for an ultra-low-head pre-packaged turbine system, you may be able to install it yourself with the help of the supplier. To install other micro-hydro systems, you'll need either earth-moving, mechanical and electrical skills or a qualified contractor.

Once your system is installed, be prepared for a number of weekly, monthly and yearly maintenance tasks, from keeping the intake pipe unclogged to greasing the machinery.

If you use batteries to store your electricity, you'll need to top them up and equalize them regularly.

Additional Resources

Publications and Websites

Natural Resources Canada has published two helpful guides: An Introduction to Micro-Hydro Power Systems and Micro-Hydropower Systems: A Buyer's Guide. You'll also find information on low head and ultra low head hydro at the Integration of Renewable Energy on Farms website.

Online Tools

The Ontario Ministry of Natural Resources' Water Power Atlas can help you identify promising sites for waterpower development.

Online Courses

Alterative Energies Ltd. offers an online course on designing and installing your own micro-hydro system.

Associations

• Ontario Waterpower Association