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A multi-parametric sensitivity analysis of Solar Water Heater (SWH) systems was undertaken for the city of Brisbane in Australia using computational models calibrated by experimental data. The models were calculated using EnergyPlus 8.6. The following technical specification parameters were assessed in the modelling: (i) solar collector efficiency; (ii) solar collector area; (iii) tank volume; (iv) tank heat loss; (v) electric back-up heating power rate; (vi) electric back-up heating position (height) for vertical tanks; and (vii) electric back-up heating temperature range. The site-specific parameters included: (i) solar collector direction; (ii) solar collector tilt angle; (iii) solar collector shadowing; (iv) solar collector dust accumulation; (v) hot water pipe insulation; (vi) hot water pipe length; (vii) electricity tariff time-of-use; and (viii) cold water temperature. User behaviour patterns were comprised of the following parameters: (i) end-use water temperature; (ii) end-use water demand; and (iii) end-use time-of-use. For all parameters, two system types were assessed, namely: (i) thermosiphon systems with natural (passive) circulation in collectors and unstratified horizontal hot water storage tanks; and (ii) split systems with forced (pumped) circulation in collectors and stratified vertical hot water storage tanks. The performance of SWHs was analysed considering both energy performance indicators (i.e. total and peak-hour energy consumption, solar fraction and energy intensity) and level of service indicators (i.e. compliance with recommended hot water temperatures for Legionella spp. control and comfort levels). Notwithstanding the prevalence of thermosiphon systems among SWH technologies, results indicate that split systems usually outperformed thermosiphon systems both in terms of energy efficiency and level of service, and hence should be a preferred option for energy efficiency initiatives and policies. [ABSTRACT FROM AUTHOR]

In this study, a MATLAB/SIMULINK model of a solar water heater has been developed and simulated for an aviculture building in Tehran, Iran. The thermal behavior of the subsystems, such as temperature changes of the collector, heat exchanger, and storage tank, etc., has been determined. Three different simulation approaches have been considered. The thermal performance of the system was evaluated by proposing two auxiliary heaters within the storage tank and using them in three different cases. The results showed that the collector surface area has a great impact on the absorber plate average temperature. Also, a greater amount of auxiliary heating would cause the inlet and outlet of the heat exchanger to be equal for a much longer time and thus reduce the heat exchanger efficiency. [ABSTRACT FROM AUTHOR]

The optimization of a solar domestic hot water system (SDHWS) for the provinces in certain climate zones of Turkey was investigated in the present study. The optimum design of the system was divided to a three level structure. The simulation level (TRNSYS), the Generalized Pattern Search (GPS) optimization method Hooke-Jeeves Algorithm level (GenOpt) and the interface for the communication between those two levels (TrnOPT). Taking into account the financial (life cycle cost) analysis, the optimum collector area, the optimum collector slope and optimum hot water storage tank volume were determined for each province. The annual simulation of the SDHWS was accomplished with the determined optimum size and the monthly auxiliary heating rate, the monthly solar fraction and the monthly collector efficiency were calculated for each province. In the designed system, the highest auxiliary heating rate was determined 379.63 kWh/month in Hakkari on October and the lowest auxiliary heating rate was determined 177.48 kWh/month in Izmir on October. The lowest monthly solar fractions from the solar water heating system were calculated for Edirne as 8% in December and as 17% in January. The costs of meeting the annual auxiliary heating rate and the annual energy rate to load with electricity and natural gas were compared. The effects of increased utilization of the SDHWS in buildings on the energy supply of Turkey were addressed. [ABSTRACT FROM AUTHOR]

The maximum electricity conversion efficiency of the Solar Photovoltaic panel is 8-18% under the Standard Test Condition (STC) temperature of 25 °C. The atmospheric temperature of lndian climatic condition is mostly above 30 °C - 45 °C, it incites 30 °C-80 °C heat over the panel since black body of the PV panel observe more heat, and this temperature majority affect the electrical efficiency of the panel. The newly designed Glass to Glass Photovoltaic Thermal System (G2G-PVTS) is a combined Photovoltaic (PV) and Flat Plate Solar Water Heating System (FPSWHS). In this technology, the water act as a coolant inside the Copper fins and it absorb the heat of the PV panel and stored in the insulated storage tank by way of natural flow of water. The test result shows that the G2G-PVTS electrical efficiency was 0.7% higher than conventional G2T-PV panel, and in addition that 44.37% of thermal efficiency was also stored The simultaneous conversion of electrical and thermal energy was obtained by this system with effective space utilization. The overall efficiency of the G2G-PVTS panel was improved. [ABSTRACT FROM AUTHOR]