Performance metrics & physics
Convection
Convection is heat transfer via fluid (air or liquid) movement, contributing to vehicle cabin heating when warm interior air recirculates without effective aircon flow.
Convection inside a stationary car works against the occupant — warm air rises and pools at head level, while cooler air sits near the floor. Without aircon, this thermal stratification is uncomfortable.
Window films don't address convection directly, but reducing the heat load means aircon needs to do less work to overcome convective discomfort.
For Singapore EVs in particular, lower aircon load translates directly to longer range — measurable in 5–10% range gains in real-world conditions.