Question

Planning is underway for a new hydroelectric power plant, and you have been asked to provide an engineering opinion on the best site for the power plant to be located. Two main sites have been identified for the plant. Site 1 is located at the base of a dam wall, with the waterline located 70 m above the turbine. The location has good accessibility for the construction crew, meaning that they are able to bring in a state-of-the-art turbine-generator system. The overall efficiency of the system is 85%, while the efficiency of the turbine alone is 92%. The geology of the area means that a 1.4 m diameter feedpipe can be installed, through which water can be supplied to the turbine at an average velocity of 6 m/s. Site 2 is also located at the base of a dam wall, with the waterline located 100 m above the turbine. Accessibility to this site is not as good as for Site 1, and as such there are restrictions on the type of turbine-generator system that can be installed. While it will be possible to use the same generator as would be used at Site 1, an alternative turbine is required. The identified turbine has an efficiency of 89%. Additionally, because of the more complex geology, a narrower feed pipe can be drilled (diameter = 0.8 m), through which water is supplied at a higher average velocity of 13 m/s. A further consideration is that the cost of distributing power from the two sites is slightly different. Power can be distributed from site 1 at a cost of $0.053/kWh, while the cost of distribution from site 2 is slightly lower at $0.051/kWh. To be competitive in the market, the company intends to retail its hydroelectric power for $0.10/kWh Provide an engineering opinion (of no more than six sentences) as to which site is superior for locating the hydroelectric plant. Your opinion should cover: • Any relevant assumptions you have made • Any thermodynamic considerations (relevant energy balances, etc.) • The power available from each site • The amount of power generated by the proposed plants • The profitability of the proposed plants • Advice as to which site is better for situating the power plant and why

Answer 1