Are EVs Still the Fleet of the Future?

A few years ago, fleet electrification felt inevitable. The only real question seemed to be how quickly internal combustion engines would give way to battery-electric platforms.

Today, the answer is more nuanced. Electric vehicles are firmly established in certain fleet segments and progressing steadily in others. But while much of the public conversation focuses on high-voltage battery packs and charging infrastructure, a quieter — and arguably more transformative — shift is happening underneath the hood.

The real long-term story may not just be the move from gasoline to electrons, but the transition from 12-volt to 48-volt vehicle architecture.

EV Adoption: Steady, but Selective

Electrification is advancing fastest where vehicles follow predictable routes and return to base daily. Light-duty fleet vehicles have led adoption, with EVs representing about 9% of new U.S. light-duty vehicle sales in 2023.

Transit agencies are further along in heavier applications, with thousands of zero-emission buses already operating or on order. But in medium- and heavy-duty commercial fleets overall, adoption remains early — still well under 1% of registrations as of 2024.

In other words, EVs are growing — but the transition is not uniform across all vehicle classes or duty cycles.

The High-Voltage Revolution… and the Part that Hasn’t Changed

Battery-electric vehicles replace internal combustion engines with electric motors powered by high-voltage battery systems — typically around 600 volts, and in some cases even higher. This is a dramatic shift in propulsion technology.

But here’s what often gets overlooked: Most EVs still rely on a 12-volt secondary electrical system. Lighting, controls, infotainment, telematics, safety systems, auxiliary equipment… the vast majority of these functions continue to operate on familiar low-voltage architecture. Even in fully electric vehicles, a DC-DC converter (80206) steps down high-voltage battery power to maintain the 12V system.

For fleets and vehicle builders, that means much of the electrical integration work remains grounded in traditional low-voltage design — at least for now.

The Coming Shift: From 12V to 48V Secondary Systems

While propulsion grabs headlines, another consequential change for vehicle electrical design is the industry’s gradual move toward 48-volt secondary architecture. This transition is being driven by a simple reality: Modern vehicles demand more power than ever before.

From air conditioning systems, seat heaters, driver-assistance systems, and infotainment platforms to auxiliary lighting, pumps, power steering, and electric compressors: the electrical load in today’s vehicles has surged.

Under a 12V system, higher power means higher current. Higher current requires thicker wire, which adds weight, cost (especially copper), packaging complexity, and routing challenges. For OEMs working to improve fuel economy and extend EV range, those burdens matter.

Shifting to 48V significantly reduces current for the same power output. In fact, quadrupling voltage allows equivalent power delivery at one-quarter the current. That enables smaller wire gauges, lower copper usage, reduced weight, and improved efficiency.

There’s historical precedent for this shift. In the 1950s, the industry moved from 6V to 12V systems for similar reasons — rising electrical demand and increasing copper costs. Doubling voltage cut current in half, reducing wire size and improving efficiency.

Today, 48V is viewed as a practical “sweet spot.” It dramatically increases electrical capacity while remaining below the 60V threshold typically considered safe from shock hazards. It also benefits high-demand components like starter motors and electric compressors, which can operate more efficiently and deliver greater torque with less copper.

Mixed-Voltage Vehicles: The New Reality

The transition won’t be immediate — and it won’t be universal. Some low-power devices will remain on 12V systems for years. Battery-electric vehicles may simultaneously contain high-voltage propulsion systems, 48V secondary architecture, and 12V legacy subsystems.

That creates a mixed-voltage environment inside a single vehicle. And that environment introduces new engineering considerations including:

• Preventing arcing through proper terminal spacing
• Ensuring adequate sealing to reduce electrochemical corrosion
• Maintaining clear separation between circuits of different voltages
• Redesigning connectors, fusing, contactors, and power distribution components
• Retooling systems long standardized around 12V architecture

The industry’s decades-long reliance on 12V means this shift requires thoughtful redesign — not just incremental upgrades.

What this Means for Fleets and Builders 

Whether a vehicle is electric, hybrid, or internal combustion, one thing is clear: Electrical systems are becoming more powerful, more complex, and more integrated.

For fleets evaluating electrification, the decision isn’t only about propulsion. It’s about ensuring the vehicle’s electrical backbone can safely and efficiently support evolving power demands.

For OEMs and upfitters, it means planning for a future where:  

• Higher-voltage contactors and protection components are required
• Power distribution modules must accommodate new voltage classes
• Connectors, tape, heat shrink, and protective sleeving must withstand increased electrical stress
• Mixed-voltage safety design becomes standard practice

Suppliers across the industry are already adapting — expanding higher-voltage product options and engineering components designed specifically for 48V and mixed-voltage architectures.

For more information see Essential Components for Secondary Electrical Systems in EVs and How to Make the Leap to 48 Volt Architectures.

So — Are EVs Still the Fleet of the Future?

Yes, eventually. But perhaps more importantly, electrification of vehicle systems is the future — regardless of drivetrain. The move to high-voltage propulsion is only one layer of transformation. Beneath it, the shift from 12V to 48V architecture may ultimately have a broader and longer-lasting impact on how vehicles are designed, built, and serviced.

The OEMs and upfitters that plan for this evolution — not just the motor, but the electrical architecture — will be best positioned for whatever the next decade brings.