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The purpose of this study is to develop a thermoelectric egg incubator (TEI) integrated with a thermal energy storage (TES) system, using electricity from photovoltaic (PV) cells in order to operate without on-grid electricity. The TEI was constructed with the same dimensions as a commercial egg incubator (CEI), which was made to the required dimensions for hatching 24 eggs per period of 21 days. The TEI was designed with 2 operating modes of heat sources: a thermoelectric (TE) module used for daytime operation and a TES containing phasechange materials (PCM) which supplied heat to the TEI for nighttime operation. The PV panels were designed to be the primary energy source for generating 360 W of electricity, which was supplied to heat sources of TEI according to the energy load for providing fertile chicken eggs (24 eggs/hatching). The incubating temperature and relative humidity (RH) inside the TEI-TES were controlled under optimum environmental conditions for hatching (36-39°C and 60-80% RH) to stimulate embryonic growth. As a result, the TEI-TES achieved and maintained an optimum incubating temperature in the range of 36.7-38.8°C and the correct RH of 66±0.2 % in the warm weather of Thailand over the incubating period of 21 days. The TEI-TES was able to maintain optimum environmental conditions for chicken-egg hatching, and its performance was comparable to that of the CEI. The working mechanisms of the TE module and TES are also discussed. The results show that the TEI-TES with PV panels as the primary energy source is suitable for use in remote areas which have no on-grid electricity supply. [ABSTRACT FROM AUTHOR]

Lead-free (1-x) Ba0.85Ca0.15Ti0.90Zr0.10O3 x Bi0.80Ba0.20FeO3 [(1-x)BCTZ-- xBBF] ceramics, with BBF content (x) between 0 and 0.4, are prepared via the solid-state combustion technique. The effect of BBF content on the phase formation, microstructure, and electric and magnetic properties of BCTZ is studied. From the Rietveld refinement analysis, the BCTZ ceramic shows coexisting orthorhombic and tetragonal phases, with a ratio of 35.4:64.6 and the percentage of the tetragonal phase continuously increases when x increases from 0.02 to 0.1, and becomes purely tetragonal at x ≥ 0.2. When x increases, the average grain size, density, and relative density continuously decrease while the unit cell volume enlarges. The dielectric constant at room temperature (εR) tends to decrease while the dielectric loss at room temperature (tan δR) increases with increased BBF content. For x = 0, a pure BCTZ ceramic, a well-saturated P--E loop is observed with a polarization (Pr) and coercive field (Ec) of 8.94 µC cm-2 and 4.06 kV cm-1, respectively. The ferroelectricity drastically decreases with x=0.02. For x≥ 0.06, the leakage current increases, which suppresses the ferroelectricity. With no BBF content (x=0), the ceramic has diamagnetic properties that change to paramagnetic properties with x=0.02--0.06 and finally to ferromagnetic properties when the BBF increases between 0.10 and 0.40. For x=0.10--0.40, the remnant magnetization (Mr) continuously increases. [ABSTRACT FROM AUTHOR]