Comparative efficiency assessment of novel multi-flash integrated geothermal systems for power and hydrogen production

This paper focuses on a comparative assessment of multi-flash (single to quintuple) geothermal power generating systems integrated with electrolyzers through three definitions of energy and exergy efficiencies. The Operating parameters such as ambient temperature and geothermal source temperature are varied to investigate their effects on the respective efficiencies of individual and integrated systems. The effect of increasing the number of flashing steps on the efficiencies is also studied. The results show that second and third definitions of efficiency provide with same trends, whereas the first definition provides a completely opposite trend. It is also noticed that a rise in ambient temperature and geothermal source temperature results in higher energy and exergy efficiencies and that the quintuple flash system is found to be the most efficient for practical applications. For a base condition, it is observed that overall system exergy efficiency varies from 6.52% to 47.29% with increase in the number of flash from single flash to quintuple flash.

► Energy and exergy analysis of novel multi-flash integrated systems.
► Comparative study of energy and exergy efficiencies of integrated systems.
► Comparison of three different efficiency definitions.