A river runs through it

It was a white Christmas but a wet new year so the stream that runs under our house is in full flow. I posted this photo on facebook and within seconds one of my former students, Erik Torstensson, commented about installing turbine. So I thought I'd take some measurements. Armed with a 10 litre bucket I found that about 1/3 of the stream filled it in 3 s, so the total flow rate is 10 kgs-1. I looked up on a map to find the difference in height which turned out to be 20 m.

The power is therefore 2 kW, if it's 50% efficient that would be 1 kW. With the present price of electricity that might be worth doing however:

  • the river is rarely so full.
  • we would need to have some sort of collection point at the top.
  • we would lose our water feature inside an ugly plastic pipe.