A water turbine to run a generator? Let's try some math to quantify requirements!
Let the average power required be 2.0kw, drawn from an inverter and battery storage charged by a generator and turbine. Let the additive efficiencies of all the above devices = 50%
Then 4.0kw continuous water potential power is required.
4000W = 5.36HP = 176944ft.lb/minute = 2950ft.lb/second
Using a hill to create a head of water for the machine, say a hill 6ft high.( Modest, but this is Norfolk after all!)
176944/6ft = 29491 lb water/minute needed.
= 2950 Imperial gallons per minute= 4,250,000 gallons per day net.
Sufficient energy must remain in the water for it to flow out of the machine, say a gross water requirement of 6 million imp. gallons per day.
Or, try using the kinetic energy contained in the flow of the culvert. Let water velocity = 3mph, (modest walking speed), = 4.4 ft/ second.
KE = 0.5mv2/g ; the mass of water required
= 2x32.2x49/4.4x4.4 = 163lb water/ second.
16.3 imp. gallons per second= 58,680 imp. gallons per hour. Again, additional water is required to drive exhaust stream, say 75,000imp. gallons per hour, 1,8 million imp. gallons per day.
This would dimension the culvert at only 1ft wide by 7.4" deep, with water travelling at 3mph! In practice a combination of its existing kinetic energy plus as high a fall as practical for the turbine feed pipe would be aimed at.
nb. An undershot wheel shoved directly in the culvert will be nowhere near as efficient as a turbine.
Alan
