Replacing existing valves with a micro-turbine and generator system
This project was an upgrade on an existing reservoir created by a dam on Mark Creek, which supplies water to the City of Kimberley.
Water flows from the supply intake to a head tank through a 760mm diameter water supply pipe. The water level in the reservoir is 35m (50 psi) elevation above the water level in the head tank. The water level in the head tank was controlled by a series of float valves which discharged water into the head tank from a header located in a small building on top of the tank, fed from the water supply main.
As water discharged through the float valves, the pressure was broken to atmosphere and the water flowed to the City. As demand increased and the water level continued to drop in the head tank, the float valves opened sequentially as required to meet the demands.
The micro-turbine in the replacement system utilizes the energy of the water to generate power. Water from the supply pipe is directed through an Impulse Turgo Turbine with a nominal capacity of 25 kW. Two nozzles modulate to control the rate of flow through the micro-turbine to match the city water demand as measured by the water level in the head tank. Water discharges to the head tank below the micro turbine.
The old float valve system has been retained as a backup.
The power will be used to supply power to the adjacent chlorination facility. Power generated from the micro-turbine and generator is anticipated to be in excess of that required for this facility, and excess power will be delivered to the BC Hydro grid through BC Hydro’s New Metering Program, offsetting the City’s electricity costs.