assessing hydro potential

Small-scale hydropower projects are becoming increasing popular for homeowners in remote places, with a small stream near their houses.

Hydropower can be an economical and clean source of electricity.

Hydropower Potential

The small hydro-electric potential varies widely from region to region within each country, and from site to site.

In the United States, for instance, that potential is high in the west coast (namely in the northwest), while in countries like Canada, Brazil or Russia that potential is rather dispersed all over their territory.

For an assessment of regional hydropower potential in USA, see the Idaho National Laboratory map.

Assessing the Hydro Potential of your site

The amount of power you can get from your hydro project is crucial. And to assess it, you should figure out the power output and the constancy of the water flow over the year.

To know the amount of power a hydro project can yield, consider two elements: 1) the vertical distance associated to the water falling (the Head) and 2) the amount of water falling (the Flow).

The Department of Energy suggests an equation to calculate the hydro power output in Watts, based on the Head and Flow of the system. It multiplies both, and divides the result by 10:

Power (Watts) = [Head (feet) x Flow (gallons per minute)] : 10.

This formula will give you the system’s output in Watts.

Expert assessment

Even if your estimates are sufficiently accurate, you still need the help of a qualified professional to determine the feasibility of the project and its design.

Technical Details

For technical details on how to determine the head and the flow of a hydropower site, see the EERE’s pages: Site’s Head and Site’s Flow.

See also, for some economics on Micro Hydro Power systems: Feasibility of Small Hydro Projects

Hydropower Worldwide

China is a leader in the small hydropower systems - it has already surpassed Canada as the world leader in large hydropower systems -, but many other countries worldwide are focusing part of their energy policy on small hydropower plants, and the installed capacity of micro-hydro is estimated to grow steadily in the next few years (around 55 GW in 2010, according to the WEC/World Energy Council.

Countries like Australia, New Zealand or Canada are also betting heavily in small hydropower projects for small communities and homeowners.