Converting hydraulic resistance energy of the system into electricity

Introduction. A gravity conduit with a control valve and a pressure regulator in the gravity water-supply pipe is considered under conditions when the hydraulic regime of the water-supply system is not disturbed. In relation to such a system, the problems of converting the energy of local artificial hydraulic resistance into electricity are investigated.Materials and Methods. Literature that highlights the possibility of using microturbines for power generation in water systems was studied. The actual values noted by the continuous pressure recorder (logger) for 12 hours were presented, as well as the water consumption by the turbine at a given unit section (the average for a year), and the pressure differential. It was noted that the use of small hydroelectric power plants in water supply systems significantly reduced the cost of their operation. The indicators of water consumption in the hydroturbine unit during the year, broken down by months, were given. The maximum power at the turbine inlet was calculated. The principles of selecting the type of hydraulic turbine were described. The average efficiency values for different elements of the hydroturbine plant, the average parameters of the power of the small hydro and the corresponding indicators of the average monthly electricity generation were indicated.Results. Equipping the units under study with specially designed turbines can enable to obtain electrical energy through converting artificially created by local resistance and extinguished mechanical energy. It is possible to apply the approaches described in this article when replacing many of the pressure control units of the Yerevan City Network system. The productivity of a small hydro power plant was predicted, as well as the terms of its construction and operation - for 2 years and 30 years, respectively. The construction and maintenance costs were calculated in advance. The expected data on income, expenses, and net profit are given. It is indicated that it will potentially be close to 6 million drams per year. The analysis of the data allowed us to conclude that the internal rate of return will be at the level of 10.4%, and the payback period is 9 years.Discussion and Conclusions. We recommend replacing the regulator with a hydroturbine having the same hydraulic resistance and automatic flow control in the system. The conclusions were confirmed by the energy and economic indicators of the hydroturbine plant located on the section of the Arzakan - Yerevan main water pipeline.