Analysis of the thermal efficiency of a compound parabolic Integrated Collector Storage solar water heater in Kerman, Iran. (December 2019)

• Record Type: Journal Article
• Authors: Panahi, Rashid; Khanjanpour, Mohammad Hassan; Javadi, Akbar A.; Akrami, Mohammad; Rahnama, Mohammad; Ameri, Mehran
• Is Part Of: Sustainable energy technologies and assessments. Volume 36(2019)
• Publication Date: 2019-12
• Subjects: DT Diameter of storage tank (cm) -- VT Volume of storage tank (liter) -- CR Concentration Ratio -- ICS Integrated collector storage -- SWH Solar water heater -- ηd Mean daily efficiency -- rT Radius of storage tank -- DTmD Mean water temperature difference during the day -- CPC Compound-parabolic-concentrator -- Wα Width of concentrator -- LT Length of storage tank -- Lα Length of aperture -- Mw Mass of water -- Cp, w Specific heat of water -- Af Aluminum foil -- T1 Final storage water temperature -- Tma Average ambient temperature -- Mb Mirror booster -- ω Involute concentrator's angle (°, rad) -- ώ Upper involute concentrator's angle (°, rad) -- Aα Area of aperture (cm2) -- Ar Area of absorber (cm2) -- C Maximum mean daily efficiency coefficient -- QW Heat in the tank of water storage (J) -- QR Integrated solar radiation on the aperture of the system (J) -- TmN Mean water temperature difference during the night -- Α Acceptance angle of the system (°, rad) -- DtD Time interval during daily operation -- Ta Ambient temperature -- G Incoming solar radiation intensity -- Dt Time interval -- Us Coefficient of thermal losses during the night -- Gm Mean daily solar radiation intensity -- T0 Initial storage water temperature -- t0 Initial time -- t1 Final time -- SS Steel sheet -- DTmN Mean water temperature difference during the night -- Ψ Parabolic concentrator's angle (°, rad) -- ψ́ Upper parabolic concentrator's angle (°, rad); Solar water heater -- Integrated Collector Storage -- Compound parabolic concentrators -- Thermal performance -- Sustainable development; Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2019.100564
• Languages: English
• ISSNs: 2213-1388

Abstract

Abstract: This paper presents an experimental study involving the design, manufacturing and testing of a prototype integrated collector storage (ICS) solar water heater (SWH) in combination with a compound parabolic concentrator (CPC). The thermal efficiency of the developed system is evaluated in Kerman (latitude 30.2907° N, longitude 57.0679° E), Iran. The developed system is intended to supply hot water for a family in remote rural areas. A 6-month experimental study was undertaken to investigate the performance of the ICS SWH system. The mean daily efficiency and overnight thermal loss coefficient of each experiment were analyzed to examine the appropriateness of these collectors for regions in Kerman. The results showed that mirror has the highest mean daily efficiency (66.7%), followed by steel sheet (47.6%) and aluminum foil (43.7%). The analysis of hourly and monthly operation diagrams for variations of water temperature for the developed ICS system showed that by increasing the amount of radiation entering the water heater, the thermal efficiency of the system decreases, such that the highest efficiency was in April and the lowest in July. With the distribution of radiation intensity in the months of August and September, the thermal efficiency of the system increased. This regional study illustrates how selecting a proper concentrator can increase the thermal efficiency of this solar-based system. It also shows how the temperature gradient between the ambient air and internal water in the storage tank can influence the performance of such systems, and how a controlled amount of hot water withdrawal can affect the system's efficiency. Developing the ICSSWH system is an ideal sustainable solution in countries that benefit from a large amount of solar intensity.