Influence of equipment size and installation height on electricity production in an Archimedes screw-based ultra-low head small hydropower plant and its economic feasibility

Abstract

Simulations of electricity production are based on archived hydrological data for a water stream with an ultra-low head of 1.4 m in an area with high precipitation. Mathematical models of the equipment, designed for 1.4 m and 1.5 m heads, are constructed from the manufacturer’s data. Conditions for the safe operation of an Archimedes screw and strict limitations of water utilisation are taken into account in the simulation model of the small hydropower plant (SHP). By simulating the equipment at a baseline installation height, the benefit of prolonged operation of the SHP is also shown. The elevation of the equipment at 5 cm or 10 cm away from the baseline moderately increases production, as well. When a larger unit is placed at the proper installation height, it achieves roughly the same production as optimally designed bespoke equipment, if not more. Deploying equipment of identical size on sites with varying nominal heads avoids bespoke installations, and can significantly decrease equipment costs. A more competitive unit price of electricity is achieved, owing to the lower investment costs, and the economic viability of the SHP projects on sites with ultra-low heads is improved.