Feasibility of Hybrid Desalination Plants Coupled with Small Gas Turbine CHP Systems

Abstract

Nowadays, several technologies for desalination processes are available and widely employed. However, they consume a considerable amount of energy and involve high capital and operating costs. Therefore, the techno-economic analysis of a system coupling different energy sources with the desalination processes is of value. The possibility of coupling a small gas turbine combined heat and power system (GT CHP) with hybrid desalination plants (HDPs) has been assessed in this study. The proposed gas turbine power generation system, based on a single-stage centrifugal compressor and an uncooled centripetal turbine, provides design simplicity and reasonable installation costs for the power generating plant. The hybrid desalination technique, based on the use of two different desalination technologies, i.e., Reverse Osmosis (RO) and a thermal desalination process, has been chosen to better exploit the electrical and thermal energy produced by the mini CHP plant. The proposed solution is numerically investigated from both thermodynamic and economic points of view, and the results of the thermodynamic analysis of the cycle are used as input for the evaluation of the amount of freshwater produced and of costs. The economic assessment of standalone desalination systems is also shown for the comparison with the hybrid solutions here proposed. Results show that the total cost of the water produced by MED + RO was less than the total cost of the water obtained by MSF + RO, and that the energy cost of MED + RO hybrid desalination system was about 15% less than that for stand-alone RO desalination technology. Thus, the MED + RO hybrid desalination system can be considered a promising solution for the coupling with the proposed mini GT CHP plant, which, due to the small size and cost, as well as the easy installation, can be easily applied in off-grid or remote areas.

Energy Storage for Water Desalination Systems Based on Renewable Energy Resources

“…In fact, compared with the WDSs powered by RERs, hybrid applications exhibit high flexibility of fresh water capacities, simple system design, and easy management. The inputs of the hybrid systems are any RER, hybrid renewable energy, or hybrid renewablefossil fuel resource; on the other hand, the outputs are hydrogen, biofuels, electricity, potable fresh water, heating, cooling, etc., [139][140][141]. The multiple utilities of hybridization WDSs make for low levelized costs of electricity and a low environmental impact.…”

Preliminary Design of a Mini Gas Turbine via 1D Methodology

“…A general trend related to such engines towards the introduction of small-sized units can be seen. Inland-distributed generation in the context of the growing amount of renewable energy systems on the grid [1] and key applications such as clean water production via desalinization [9] would benefit from the use of compact combined heat and power (CHP) GT units, from both economic and performance perspectives. A similar need for compact machinery has been observed in the fields of aircraft propulsion [10] and naval onboard energy generation [11,12], where such machines are seen as valid options for compact layouts.…”