The power available from your river is a function of the flow of water and the drop (head). We were able to get estimates of flow from the Environment Agency but there are formulas for estimating flows over a weir that are a function of the width of the weir and the height of water over the weir's edge. The estimates suggested that the flow would exceed 1 m³/sec for c.66% of the year and this was used as the flow to size the system. With 1.0 m³/sec of flow, an effective head of 1.5m and allowing for 75% efficiency factor indicated a power potential of 11KW
Power = Head (m) x Water flow (m³/sec) x Water density (kg/m³) x 9.81 (coefficient of gravity) = 1.5m x 1.0 m³/sec x 1000 x 9.81 x 75% efficiency = 11 KW
Potential to serve 14 average homes...
Allowing for 70% efficiency factor implies... Potential for 70,000 KWhr per year or electricity consumption of 14 average homes