Palma del Río is a municipality located in the south of Spain, in Andalucía, and has about 22,000 inhabitants. The drinking water supply system has a treatment plant that pumps the treated water to a reservoir located in an upper area.
From that reservoir, the water is transported through a pressurized pipe to the municipality. To avoid breaks in the water network, the transport pipe has a pressure regulating valve that reduces the supply pressure of the municipality. This valve works 24 hours a day, 365 days a year, dissipating excess pressure in the form of noise and heat and without any type of energy use.
To take advantage of the energy dissipated by the pressure regulating valve, the water turbine has been installed in parallel to it. In this way, part of the flow is diverted by the water turbine and the rest continues to pass through the reducing valve.
The water turbine works with a flow rate of 20 liters / second and a pressure drop of 18 meters. The electrical power generated under these conditions is 2.5 kW. which means that 70% of the available hydraulic energy is transformed into electrical energy
Electrical panel and the grid connection inverter have been installed in a recently built concrete box. The electrical energy generated is used 100% for self-consumption in the treatment plant itself, thanks to a 150 meter long electrical line installed for this purpose.
Due to the power consumption of the plant is so much higher than the power generated by the water turbine, there are no surpluses of energy to be exported to the electricity grid.
Thanks to the water turbine at the outlet of the Palma del Rio drinking water tank, significant savings are achieved in the purchase of electricity. The water turbine is capable of generating 21,900 kwh per year, contributing to the reduction of the energy bill of the treatment plant.
Installation date: February 2020