Measuring Flow for Hydropower Site
To see if a microhydropower system would work for you, determine the vertical distance (head) available and flow (quantity) of the water.
To build a microhydropower system, you need access to flowing water on your property. A sufficient quantity of falling water must be available, which usually, but not always, means that hilly or mountainous sites are best. Other considerations for a potential microhydropower site include its power output, economics, permits, and water rights.
To see if a microhydropower system would work for you, you will want to determine the amount of power that you can obtain from the flowing water on your site. This involves determining these two things:
- Head -- the vertical distance the water falls
- Flow -- the quantity of water falling.
Once you've calculated the head and flow, then you can use a simple equation to estimate the power output for a system with 53% efficiency, which is representative of most microhydropower systems.
Simply multiply net head (the vertical distance available after subtracting losses from pipe friction) by flow (use U.S. gallons per minute) divided by 10. That will give you the system's output in watts (W). The equation looks this:
[net head (feet) × flow (gpm)] ÷ 10 = W