Ferroelectric ceramics, Ba0.95Sr0.05(Ti0.95Zr0.05)1–xSnxO3 (BSTZS), with varying Sn content (x = 0%, 2.5%, 5%, and 7.5%), were synthesized using the conventional solid-state reaction method. This study delves into the temperature-dependent ferroelectric behavior of BSTZS ceramics, with a focus on their potential for thermal energy conversion, assessed using the Olsen cycle. Operating the cycle within the temperature range of 25 to 110 °C and applying an electric field ranging from 0 to 30 kV/cm, we achieved an impressive maximum energy conversion density of 175 kJ/m3 per cycle for the composition with x = 5%. Notably, when compared to other lead-free ferroelectric materials, these results demonstrate a significantly high energy density, particularly for relatively modest electric fields and temperature gradients. Considering the impact of temperature on hysteresis parameters, we also provide insights into the relationship between remnant polarization (Pr) and temperature (T), along with scaling relations. The power-law exponents for hysteresis parameters in the examined compositions are determined. The scaling relations for coercive field (EC) and remnant polarization (Pr) are expressed with respect to T as follows: EC T −0.3803, EC T −0.8806, EC T −0.6010, and EC T −0.0389 for x = 0%, 2.5%, 5%, and 7.5%, respectively. Similarly, Pr T −0.364, Pr T −0.962, Pr T −2.170 and Pr T −4.018 for x = 0%, 2.5%, 5%, and 7.5%, respectively. Furthermore, we have employed the Arrhenius law to calculate the average activation energy for all materials. This calculation helps us estimate the behavior of back-switching polarization (Pbc) as a function of temperature.