Electric delivery vans are becoming a bigger part of last-mile logistics, but hot climates create a real problem for fleet operators. In Phoenix, cargo area temperatures inside these vans can climb past 130°F during the summer. That kind of heat doesn't just make the job harder on drivers, it can also chip away at battery performance and usable range.

3M set out to test whether its Cooling Film could help, and the results from a year-long field study are worth a look.

The Problem: Heat Buildup in Cargo Areas

Last-mile delivery routes tend to run during the hottest stretch of the day, typically between 11 a.m. and 4 p.m. Vans spend a lot of that time moving slowly or sitting still, which limits airflow. Since cargo areas aren't air-conditioned, heat builds up fast and takes a long time to dissipate.

For a global logistics company running electric vans in Phoenix, this created a noticeable gap between the air-conditioned cab and the much hotter cargo area. Drivers moving back and forth between the two dealt with sharp temperature swings throughout their shifts, and the heat load added variability to battery performance.

The Solution: A Reflective Film That Needs No Extra Power

3M's answer was Cooling Film, a highly reflective performance film designed to lower vehicle heat load without drawing any additional energy. It reflects up to 85% of solar radiation and can keep vehicle surfaces up to 10°F cooler.

To see how it performed in the field, 3M installed the film on 10 electric delivery vans running standard routes and tracked cargo temperatures and energy performance over a full year.

The Results

Cooler cargo areas during peak delivery hours. During the busiest delivery window (11 a.m. to 4 p.m.), the film reduced cargo area temperatures by an average of 5.3°F. In August, the hottest month of the year, that cooling effect reached as high as 10.3°F.

More usable EV range. Even with an uninsulated, non-air-conditioned cargo area, telematics data showed the film added 4.6 to 8.6 miles of usable driving range per operating hour. Over a typical five-hour delivery period, that adds up to 23 to 43 extra miles of range, a meaningful cushion for routes that are already pushing battery limits in the heat.

Why This Matters for Fleets

Beyond the temperature and range numbers, the film's benefits line up with what fleet managers actually need day to day: quick installation that limits vehicle downtime, a durable hard-coat finish that stands up to dirt and chemicals in urban driving, and better comfort for drivers making frequent stops in and out of the cargo area.

As more fleets add electric vehicles to routes in hot-weather markets, solutions like this offer a low-effort way to protect range and keep operations running smoothly without adding energy draw or complex retrofits.

Want the full data behind these results? Download the complete 3M™ Cooling Film case study (PDF), including the temperature and range charts from the year-long Phoenix field study.

Results are based on a 3M-conducted field study and may vary by application, climate, and vehicle type. Results and outcomes of case studies or testimonials should not be interpreted as a guarantee of similar performance. Contact your Fellers representative for full 3M Cooling Film specifications and warranty information.