Design and cost analysis of regulator type hydropower plant

In this study, design and cost analysis of a typical regulator type hydropower plant in which water transmission tunnel has a free surface flow and penstocks is externally reinforced have been performed for the water intake rates in the river basin. By using Excel program annual average volumetric flow rate, annual effective volumetric flow rate, annual amount of water that will be processed for each water intake rate, friction losses, local losses, net head, the amounts of firm and secondary energy have been calculated. According to the value of project volumetric flow rate, settling basin, economic tunnel diameter, economic penstock diameter, installed power capacity, turbine type selection, number of turbines and generator capacity analysis have been conducted. Approximate cost of plant elements, plant incomes, outgoings and profitability, unit cost of energy have been calculated. Reliable volumetric flow rate, economic tunnel diameter for project volumetric flow rate (Qmaks=35 m3/s), economic tunnel slope, economic penstock diameter, net head for the gross head (Hb=100 m) and installed power capacity have been estimated to be Qgüv=7.9 m3/s, DoptT=3.30 m, 0.0037, DoptCB=2.77 m, Hn=94.63 and P= 28.129 MW, respectively. The length of forebay has been calculated to be LÇH=93 m for the hydraulic radius of 2.65 m and particle diameter of 0.27 mm. For the effective volumetric flow rate that corresponds to project volumetric flow rate, flow velocities in the tunnel and penstock have determined to be VT=2.65 m/s and VCB=3.56 m/s, respectively. For the tunnel length of LT= 2500 m, head loss has been calculated to be ΔHT=3.38 whereas it is ΔHCB=0.75 m for the tunnel length of LCB=250 m. Annual primary energy, secondary energy and total energy have been calculated to be 55.399, 90.500 and 145.899 GWh, respectively. Unit investment cost of water transmission tunnel for fresh surface has been determined to be YBT=3281 ABD$/m, whereas it is YBCB=7264 ABD$/m for externally reinforced penstock with constant wall thickness and constant diameter, 410 ABD$ per kW for electromechanical facilities, 1004 ABD$/kW for the unit investment cost of the plant and TYB=28,235,860 ABD$ for total investment cost. Annual net income, unit energy cost and profitability have been calculated to be 3,266,387 ABD$, 0.0209 $/kWh and 2.07, respectively.