Technical assessment of Multi-generation energy system driven by integrated renewable energy Sources: Energetic, exergetic and optimization approaches

Abstract

The integration of renewable resources such as solar, biomass and geothermal energies with other technologies and energy production cycles can lead to a more efficient power generation process. In addition, the development of multi-generation energy configurations can increase the sustainability, popularity, and flexibility of energy production process. In this regard, this article presents and evaluates an annotative multi-generation configuration based on solar and geothermal energies integrated with Kalina (KC), organic Rankine (ORC), refrigeration, water electrolysis, and thermoelectric (TEG) cycles. The thermal energy of the process is supplied through geothermal well, parabolic trough solar collectors (PTSC) and biomass sources. Kalina and organic Rankine cycles are installed to generate electricity. A thermoelectric generator is also embedded to increase electricity generation rate by exploiting the cycle heat losses. Meanwhile, water electrolysis and refrigeration cycles are responsible for producing a cooling load and a clean hydrogen fuel. The performance of the multi-generation configuration is evaluated and discussed from the points of view of thermodynamic, energetic, exergetic, and exergoeconomic. Moreover, a multi-objective optimization algorithm is established to optimize the exergetic efficiency and products unit cost. It was found that under the optimum case, the proposed multi-generation configuration can produce 80.1 kW and 1930 g/h of electricity and hydrogen fuel, respectively. In such a context, it can achieve 35.9 % for the exergetic efficiency and 36.95 USD per GJ for the products unit cost. Furthermore, the Levelized Cost of Electricity and hydrogen of the configuration were 5.67 USD per kg and 0.098 USD per kWh, respectively.