Analysis Of Flat-plate Collector Research Articles

Statistical analysis of solar thermal collectors in the Solar Keymark Database

Experimental, analytical, or numerical investigations are ordinarily conducted to reveal optimisation potential for solar thermal collectors. At the same time, the ‘Solar Keymark Database’ contains more than 2,000 test reports from certified laboratories featuring properties including thermal efficiency, dimensions, or optical properties. This dataset offers untapped potential for statistical analyses as an alternative optimisation approach. Hence, this paper aims to provide a) the first statistical findings of solar thermal collector properties listed in the Solar Keymark Database and b) insights into statistical relations between these properties. The key correlations observed from the analysis of flat-plate collectors were between efficiency and both gross height (R=0.30) and gross area (R=0.27). We concluded that preferable collector designs may be featured with larger area to height ratios. The analyses of evacuated tube collectors revealed a strong correlation between efficiency and transversal incidence angle modifier (R=-0.65) as a result from different tube spacing. It was noticeable that the quasi-dynamic test method reported significantly higher efficiencies (7.14 percentage points) for evacuated tube collectors, which should be carefully considered for future test procedures. Overall, the statistical analysis was in accordance with conventional bottom-up analyses and revealed insightful dependencies for the present collector data.

Theoretical and Experimental Analysis of Flat Plate Collector

In this work a flat plate collector was designed and manufactured with dimension of (100cm×160cm×20cm) and analyzed experimentally and theoretically. The designed FPC consist of Nine pipes with (2.223cm in diameter with 140cm long) welded above the plate to act as heat removal fluid passage ways. The flow inside the pipes can takes place by forced convection. However, certain energy absorbed by the plate is lost to atmosphere due to higher temperature of the plate. Effect of plate temperature on efficiency and top loss coefficient studied for different wind velocities and different air temperature. Effect of emissivity of absorber plate on top loss coefficient was estimated.The obtained result showed that the efficiency of FPC increase by 3%with the increase in ambient temperature by8 ̊C, the efficiency decrease with the increase in plate temperature and the top loss coefficient increase when the emissivity of absorber plate increase and when wind velocity increase. The comparison of result showed a good agreement.

96/00542 Economic analysis of flat plate collectors of solar energy

96/00542 Economic analysis of flat plate collectors of solar energy

Economic analysis of flat plate collectors of solar energy

Although solar energy potential in Turkey is far more than its total annual energy consumption, because of technical, economic and efficiency problems it cannot be harnessed to its fullest extent. Solar energy collecting systems have an initial cost two to five times higher than alternatives using electricity, LPG, fuel or other solid energy sources. However, their annual repair and maintenance costs are much lower than alternatives due to high energy prices. Solar systems with inflated annual costs have a minimum present value of US$867.19. Solar energy systems can be recommended for the countries that want a dependable and environmentally sound energy source. However, investment in R&D activities is necessary to reduce total cost of the system through improved efficiency and better production technology.

Extension of the Hottel-Whillier model to the analysis of combined photovoltaic/thermal flat plate collectors

The well known Hottel-Whillier model for thermal analysis of flat plate collectors is extended to the analysis of combined photovoltaic/thermal collectors in a manner, such that, with simple modification of the conventional parameters of the original model, all of the existing relations and supporting information available in the literature still apply. Beyond the basic assumptions of the original model, it is only necessary to assume that the local electrical conversion efficiency of the solar cell array (absorber) is a linear decreasing function of the local absorber temperature over its operating temperature range. Based on the extended model, examples of both thermal and electrical performance of a combined collector as a function of collector design parameters are presented and discussed.