Pico Hydro power generation calculations
James F. Hensel, Portland, Oregon USA, June 24, 2007

In thinking about the Pico Hydro videos, I created the attached spreadsheet. It has two tabs.
1. The first tab attempts to calculate the energy output of the Pico Hydro system described by Jeff Davis. This calculation assumes 100% efficiency. It is worth noting that this unit produces very little power. So I wanted to work backwards from a given fan output to determine the head and volume of water needed.
2. The second tab starts with a desired power output (replicating an electric computer fan) and calculates the head and volume needed to produce the required fan power. It attempts to take into consideration various assumed efficiencies.

I would appreciate someone more knowledgeable than I checking my calculations and thinking.

If these calculations are correct, at fan outputs of one watt or higher, this looks like a very impractical method of producing power in the kitchen unless one has a strong roof that can hold 200 pounds of water - ~25 gallons - and a method to get the water up to the roof. Even then, the water receptacle would have to be of similar volume which puts the turbine 2-3 feet off the floor and possibly in the wrong position to drive a TLUD.

Jim

James F. Hensel
Portland, Oregon USA
AIM and SkyPe: hekla57
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