An Integrated System of Electricity and Potable Water Production for Naval Cadets by Solar Concentration on POLYSUN

บทคัดย่อ

The POLYSUN software was developed to design and simulate sustainable energy systems: Photovoltaic system (PV), Photovoltaic Thermal system (PVT), Concentrated Photovoltaic Thermal system (CPVT). In this study, the CPVT system is proposed to be operated with Direct Contact Membrane Distillation (DCMD) to produce both electricity and clean water from seawater to match the requirements of a naval-cadet regiment in Royal Thai Naval Academy (RTNA), Thailand. The system will utilise heat waste from the CPVT system to desalinate seawater via the DCMD. The aims of this project are to design and simulate this hybrid system on POLYSUN to match the requirements of 100 units: 400 cadets in the regiment with the available area of 100 m x 100 m by supporting of literature reviews. The concentration tracking system of 100 collectors with nominal power at 1,878 W/collector is designed to cover the annual consumption electricity at 13,308 kWh and daily water consumption at 2,000 litres or 5 litres/person/day. The specific requirements of the DCMD are to feed seawater at 70°C and permeate water at 25°C into the DCMD with flow rate of feeding heat and permeate at 1,689 litres/hour. Furthermore, the financial assessment needs to be considered including the Levellised Cost of Electricity (LCOE) and the Return on Investment (ROI) as well as the Feed-in-Tariff (FiT) for 25-year lifetime. All in all, although the hybrid system can support both electricity and potable water for naval cadets, this system cannot make a profit within 25 years to have the ROI. The feasible reason is the daily electric consumption of naval cadets is different from other departments. Namely, the routine of daily electric consumption usually requires after sunset. In summary, this system has high-cost investment when calculated from the naval-cadet daily electric consumption and a recent policy: an electric fee of bureaucratic departments and a FiT at 3.10 Bath/kWh and 2.20 Bath/kWh, respectively.