Comparative evaluation of a natural gas expansion plant integrated with an IC engine and an organic Rankine cycle

The paper evaluates the performance of the aforementioned four configurations by means of both energy and exergy analysis. Several alternative performance indicators have been defined, calculated and discussed. Sources of irreversibilities have been identified by means of exergy analysis methodology. The fuel-product approach was used to define the exergy efficiency. Except for the reference system with a throttling valve, the analyzed systems achieve favourable values of exergy efficiency (up to 52.6%), and outstanding performance ratios (0.69-0.77), relating the energy fluxes of generated work to the fuel locally combusted in the system.