ABSTRACT
In this paper, a combined solar photovoltaic (PV) and thermoelectric (TE) generator system is investigated. The TE generator converts the temperature gradient into electricity eventually improving the overall performance of the system. A nanostructured TE material is used in this investigation and its power generation performance is compared with the traditional TE material. Using the analytical solutions, different performance parameters (e.g. heat input, power output, efficiency) are calculated and expressed graphically as a function of solar radiation and convection heat transfer coefficient. In addition to this, different performance parameters were also compared between traditional and nanostructured TE materials. Moreover, the nanostructured TE material leads to improvement in performance of TE generator due to the reduction in thermal conductivity and improvement in electrical conductivity. The TE generators have a large impact on the overall efficiency of the combined system at higher radiation.
Nomenclature
= | cross-sectional area (m2) | |
= | specific heat capacity (kJkg–1K–1) | |
= | electric flux density vector (Nm2C–1) | |
= | electron charge (C) | |
= | electric field intensity vector (Vm–1) | |
= | solar irradiation (Wm–2) | |
= | convection heat transfer coefficient (Wm–2K–1) | |
= | electric current (A) | |
= | electric current density (Am–2) | |
k | = | thermal conductivity (Wm–1K–1) |
= | Lorentz number (V2K–2) | |
= | length (m) | |
= | number of modules | |
= | Perimeter (m) | |
= | power output (W) | |
= | heat flux vector (Wm–2) | |
= | heat generation rate per unit volume (Wm–3) | |
= | heat or energy (W) | |
= | resistance | |
= | entropy (Wm–3K–1) | |
= | thickness (m), time (s0 | |
= | temperature (K) | |
= | heat transfer coefficient (Wm–2K–1) | |
= | voltage (V) | |
= | width (m) | |
= | coordinate (m) | |
= | dimensionless figure of merit |
Greek symbols
= | absorptivity, Seebeck coefficient (VK–1) | |
= | packing factor, temperature coefficient | |
= | emissivity of PV panel, dielectric permittivity (Fm–1) | |
= | efficiency | |
= | a parameter (see Eq. (24)) | |
= | a parameter (see Eq. (24)), temperature coefficient (K–1) | |
= | electrical resistivity | |
= | density (kgm–3) | |
= | Boltzmann constant (JK–1), electrical conductivity (Sm–1) | |
= | Transmissivity, Thomson coefficient (VK–1) | |
= | electric scalar potential (V) | |
= | a parameter (see Eq. (24)) |
Subscripts
amb | = | ambient |
= | Solar panel back surface temperature | |
= | cell, cold side of thermoelectric module | |
= | conduction | |
= | convection | |
= | electronic | |
= | electrical | |
= | glass cover | |
gen | = | generation |
= | hot side of thermoelectric module | |
= | internal | |
= | Lattice | |
= | External load | |
= | maximum powerpoint | |
= | n-type semiconductor material | |
= | output, overall | |
= | p-type semiconductor material | |
= | solar PV panel | |
= | radiation | |
= | reference | |
= | sun | |
= | silicon | |
= | sky | |
= | tedlar, thermal | |
= | thermoelectric module |