Temperature-Driven Variations in Stand-by Energy Use of an Electric Bus: A CAN-IoT Case Study in Campinas, Brazil

Abstract

This study presents a temperature-resolved assessment of the stand-by (parking) energy drawn by a battery electric bus (BEB) operating on the University of Campinas (UNICAMP) campus in Brazil. A CAN-IoT logger captured voltage and current at $\mathbf{1 0 ~ H z}$ from 2021 to 2024, and the resulting electrical traces were aligned with hourly meteorological data. For every parking interval, we computed specific energy consumption (SEC) and grouped the values by diurnal or nocturnal period and by season. Stand-by loads accounted for roughly 9 % of daytime and 20 % of nighttime energy in the case of the BEB in UNICAMP. Mean SEC increased from $0.054 \mathrm{kWh} / \mathrm{min}$ on cool winter nights to $0.100 \mathrm{kWh} / \mathrm{min}$ on hot summer days, exhibiting a dependence on ambient temperature during both daytime and nighttime hours. The analysis shows that neglecting temperaturedriven parking losses can underestimate daily energy demand by up to one-fifth, highlighting the need to include these effects when sizing chargers and planning routes for BEB in tropical climates.