Thermal Performance of a Solar Concentrating Photovoltaic Module with Spiral Mini Channel Heat Sink

ICP 2015: International Conference on Polygeneration, Chennai, India, 18-20 February 2015Concentrating Photovoltaic (CPV) power generation is one of the attractive choices for efficient utilization of solar energy due to its high cogeneration efficiency. The increase in temperature of solar CPV cell significantly reduces the performance. The efficiency of a CPV system can be improved by introducing effective thermal management or cooling system. In this paper, a new spiral mini channel heat sink with rectangular cross section is developed and its performance is numerically analysed using commercial CFD software ANSYS 14. The mini-channels provided high heat transfer over cell surface area and resulted in lower pressure drop. The coolant outlet temperature rise across the mini-channel is estimated as 343K in CPV module of 300 X 300 mm2 and with a pressure drop of 8.043 k Pa at a flow rate of 0.16 liter/s. Based on numerical simulations, it is found that the optimum configuration of micro-channel with 4mm width and height of 20mm, having higher figure of merit.Department of Science and Technology (DST), Government of Indi

Design a 16-cell densely packed receiver for high concentrating photovoltaic applications

A novel densely packed receiver for concentrating photovoltaics has been designed to fit a 125× primary and a 4× secondary reflective optics. It can allocate 16 1cm2-sized high concentrating solar cells and is expected to work at about 300 Wp, with a short-circuit current of 6.6 A and an open circuit voltage of 50.72 V. In the light of a preliminary thermal simulation, an aluminum-based insulated metal substrate has been use as baseplate. The original outline of the conductive copper layer has been developed to minimize the Joule losses, by reducing the number of interconnections between the cells in series. Slightly oversized Schottky diodes have been applied for bypassing purposes and the whole design fits the IPC-2221 requirements. A full- scale thermal simulation has been implemented to prove the reliability of an insulated metal substrate in CPV application, even if compared to the widely-used direct bonded copper board. The Joule heating phenomenon has been analytically calculated first, to understand the effect on the electrical power output, and then simulate, to predict the consequences on the thermal management of the board. The outcomes of the present research will be used to optimize the design of a novel actively cooled 144-cell receiver for high concentrating photovoltaic applications

Colour properties and glazing factors evaluation of multicrystalline based semi-transparent Photovoltaic-vacuum glazing for BIPV application

Low heat loss vacuum glazing offers high heat insulation for indoor space, which reduces the building’s heating energy demand. However, the transparent nature of this glazing allows similar daylight to double glazing that creates discomfort glare. Double pane semi-transparent type photovoltaic (PV) glazing introduces control of solar heat gain, daylight and generates clean electricity. The transparent portion between regularly distributed PV cells allows light penetration. Addition of these two technologies can offer low heat loss PV-vacuum glazing that will control heat loss, heat gain, and daylight and generate renewable power. In this work, two different areas of multicrystalline PV cells were employed to form 35% and 42% transparent PV-vacuum glazing. Spectral characterisation, glazing factor and entering light quality through the transparent part of this PV-vacuum glazing were evaluated. Colour rendering and correlated colour temperature of this glazing were compared with an electrically actuated switchable suspended particle device glazing

Investigation of performance and emission characteristics of a biogas fuelled electric generator integrated with solar concentrated photovoltaic system

Integration of renewable energy systems with the appropriate technology plays a pivotal role in resolving the problem of sustainable energy supply. This paper is aimed to describe the concept of integration of biomass and solar concentrated photovoltaic (CPV) energy system. The present study focused particularly on the investigation of performance and emission from a 1.4 kVA Spark Ignition, constant speed generator using raw biogas integrated in hybrid energy system. The experiments are conducted at different fuel flow rates under varying electric loading conditions. Comparing with LPG as fuel, the power deterioration is observed to be 32% on raw biogas, due to its low calorific value. The maximum power output and brake thermal efficiency using biogas is witnessed to be 812W and 19.50% respectively. The exhaust emission analysis of generator using biogas displays considerably reduced carbon monoxide and hydrocarbons whereas there is no significant difference in nitrogen oxides concentration levels while comparing with LPG, ascertaining it to be an eco-friendly fuel. The biogas fuelled electric generator integration with CPV system can attain sustainable rural energy supply.Department of Science and Technology (DST), Government of IndiaEngineering and Physical Science Research Council (EPSRC

Improving spectral modification for applications in solar cells: A review

The spectral mismatch between solar cells and incident radiation is a fundamental factor limiting their efficiencies. There exist materials and luminescent processes which can modify the incident sunlight’s properties to better suit the cell’s optimal absorption regions. This makes for an interesting area of research and promising technique for enhancing the efficiency of solar cells which is important for environmental reasons. It is intended for this review to provide the reader with historical and up-to-date developments of the application of spectral modification to solar cells and contribute to growing its impact on real-world PV devices. We concisely outline the underlying principles of three spectral modification processes: upconversion (UC), downconversion (DC) and luminescent downshifting (LDS). For each section we present up to date experimental results for applications to a range of solar PV technologies and discuss their drawbacks. With particular focus on UC, we then review how nanostructures or integrated optics might overcome these problems. Finally, we discuss practical challenges associated with advancing this approach for commercialisation and opportunities spectral modification presents; namely where future research should focus and via a cost analysis with a simple formula that can be used to determine financial viability for the deployment of this technology