A scaling law for monocrystalline PV/T modules with CCPC and comparison with triple junction PV cells

Scaling laws serve as a tool to convert the five parameters in a lumped one-diode electrical model of a photovoltaic (PV) cell/module/panel under indoor standard test conditions (STC) into the parameters under any outdoor conditions. By using the transformed parameters, a current-voltage curve can be established under any outdoor conditions to predict the PV cell/module/panel performance. A scaling law is developed for PV modules with and without crossed compound parabolic concentrator (CCPC) based on the experimental current-voltage curves of six flat monocrystalline PV modules collected from literature at variable irradiances and cell temperatures by using nonlinear least squares method. Experiments are performed to validate the model and method on a monocrystalline PV cell at various irradiances and cell temperatures. The proposed scaling law is compared with the existing one, and the former exhibits a much better accuracy when the cell temperature is higher than 40 °C. The scaling law of a triple junction flat PV cell is also compared with that of the monocrystalline cell and the CCPC effects on the scaling law are investigated with the monocrystalline PV cell. It is identified that the CCPCs impose a more significant influence on the scaling law for the monocrystalline PV cell in comparison with the triple junction PV cell. The proposed scaling law is applied to predict the electrical performance of PV/thermal modules with CCPC

In-situ thermoelectric temperature monitoring and “Closed-loop integrated control” system for concentrator photovoltaic-thermoelectric hybrid receivers

This work demonstrates a new technique that capitalizes on the inherent flexibility of the thermoelectric module to provide a multifunctional platform, and exhibits a unique advantage only available within CPV-TE hybrid architectures. This system is the first to use the thermoelectric itself for hot-side temperature feedback to a PID control system, needing no additional thermocouple or thermistor to be attached to the cell - eliminating shading, and complex mechanical designs for mounting. Temperature measurement accuracy and thermoelectric active cooling functionality is preserved. Dynamic “per-cell” condition monitoring and protection is feasible using this technique, with direct cell-specific temperature measurement accurate to 1°C demonstrated over the entire experimental range. The extrapolation accuracy potential of the technique was also evaluated

Novel hybrid III:V concentrator photovoltaic-thermoelectric receiver designs

This paper presents the design, manufacture and electrical characterization of novel hybrid III:V Concentrator Photovoltaic-Thermoelectric receivers. Addition of an encapsulating and spectral homogenizing single active surface secondary optic lens increased the solar cell electrical power output from 7.66mW (ALPHA no cooling) to 18.20mW (KAPPA with TE cooling). The effective optical concentration of the optics, based on short circuit current, was x2.4. A linear irradiance vs maximum power receiver output relationship was observed (R2=0.9978), confirming good optical alignment during manufacture and likewise internal current matching of the series-connected triple-junction cell. An in-depth COMSOL model for simulated evaluation of the synergistic thermally-dependent parameters inherent to hybrid devices was built and experimentally validated

Experimental comparison of a III:V triple-junction concentrator photovoltaic-thermoelectric (CPV-TE) hybrid module with commercial CPV and flat plate silicon modules

Concentrator Photovoltaic-Thermoelectric (CPV-TE) hybrid devices have the potential to address areas of limitation within concentrator photovoltaic devices, using the inherent flexibility and controllability of thermoelectrics. In this work, a full CPV-TE module was designed and fabricated using commercial Primary and Secondary Optical Elements (POEs and SOEs respectively). The SOE-CPV-TE hybrid receivers were characterized prior to integration within the module, and connected into a string of three receivers. The acceptance angle of the POE-SOE-CPV-TE hybrid module was experimentally characterized, and outdoor on-tracker data was obtained at the University of Jaén. For the first time, the performance of CPV-TE hybrid devices was evaluated within a 3-receiver string, and the efficiency of on-sun TE cooling was investigated.A preliminary break-even point was found at 0.3A, for active cooling verses non- cooling for the CPV-TE hybrid receivers. This highlights the future on-sun performance increases possible with further optimised CPV-TE module designs, including a low-power regime for optimised TE operation