Bill Yu¹ and Jonathan Sahagun², ¹USA, ²California State Polytechnic University, USA

StayCool is a portable, solar-powered evaporative cooling system designed to reduce extreme heat buildup inside parked vehicles [1]. The system addresses a critical comfort and safety issue, especially in hot climates where children, pets, and drivers are at risk of heatstroke [2]. It uses a Nordic nRF52840 microcontroller with temperature, humidity, and water level sensors to determine when to activate an onboard fan and misting system. Realtime data is sent to Firebase via an LTE Cat M1 modem, allowing users to monitor and control the system remotely through a mobile app. Experiments confirmed the cooling system reliably activates at threshold temperatures and that cloud-based data synchronization remains fast in most conditions [3]. Challenges like water usage, power availability, and network latency were identified and addressed through hardware safeguards and app integration. Ultimately, StayCool demonstrates a smart, autonomous, and energy-efficient approach to keeping vehicle interiors safe and comfortable.

Automatic Evaporative cooler, Comfort, Portable Unit, Solar panel, Application