Available energy assessment in water supply systems

Within European Union priorities, the problematic of available water sources have paid attention through the development of an integrated policy to reduce and control pressures and consequently leakage. In drinking pipe systems Pressure Reducing Valves (PRV) are used as dissipative devices for pressure control through a localized pressure drop. The use of microturbines or pumps operating as turbines (PT) seem to be an alternative and sustainable solution to either control the pressure as well to produce energy. This type of solution generally well accepted within renewable energy sources can be adopted as a mitigation method to control the systems loss, in particular the excess available energy which would be dissipated and the rupture occurrence. The existence of high topographic gradients are favorable to adopt these solutions, avoiding the use of high pressure pipe classes with the consequent minimization of costs and the benefit associated to energy yielding, which although depends on the daily consumptions is always a guaranteed energy. Experimental research is carried out in the Hydraulic Lab of the Department of Civil Engineering at IST, to analyze the hydraulic system response under steady and transient state conditions, as well as the development of comparative analysis between real PRV and PT. The problematic of waste available energy must paid attention through the implementation of continuous monitoring systems, in particular in drinking and irrigation systems. Furthermore, an integrated policy of water and energy systems management must be developed by using optimization analyses, as well as to encourage water companies to implement it.