What efficiency really means for mobility and robotics

Our Chief Power Architect, Brian Zahnstecher, has a column accepted for publication in IEEE Power Electronics Magazine on what efficiency actually means once a system cuts the cord. Here is his argument in brief.

Efficiency sounds like an obvious design goal. Brian’s point is that engineers must approach it differently once a system lives on a battery, with no limitless, stabilised grid behind it when things go wrong. Every choice runs through the SWaP-C lens of size, weight, power and cost, and every gram of mass is an accepted trade-off against battery life.

Untethered systems answer to two driving challenges: reducing range anxiety and making fast charging ubiquitous. Electrified mobility also tends to carry two very heavy constituents, batteries and wiring. More efficient, integrated systems attack both at once. Component size and weight come down, overhead energy falls, and range and operational time go up.

Sustainability is part of the same calculation

Most battery-powered systems carry a significant embodied carbon footprint upfront. That cost has to be justified by savings and performance over the life of the product, and even beyond it, ideally with rechargeable storage doing the work. Designing for sustainability early in new product introduction also lets supply chain partners manage SKUs and improve manufacturing quality and economics.

The column draws a distinction between two framings. Sustainable mobility means building systems enabled by greener supply chains, a Scope 3 question. Making mobility sustainable means using robotics and mobile systems to raise the efficiency of CapEx and OpEx, which is Scope 1 and 2 territory. Orchestrating the economics to favour green in both the natural and the financial sense, regardless of regulation, is an objective he calls important and admirable.

Compute and chemistry run on different clocks

Energy storage is at the mercy of chemistry and physics, so battery energy density tends to double on a timeline closer to a decade. Compute moves far faster. At its GPU Technology Conference, NVIDIA has driven a roadmap of annually doubling compute power demand that pushes AI racks beyond 1 MW before the end of this decade. It is a mismatch the mobility and untethered space is constantly up against.

Advances in storage density have still widened the field, bringing applications once considered impractical into range for mobility and robotics. Untethered systems now carry energy for compute on top of what is reserved for transport and range, and that compute is a growing capability in its own right. Intelligent power management uses it to help meet the twin goals of longer range and faster charging.

Pair energy density with power density

No single chemistry is the best of all worlds across the SWaP-C dimensions. The advantage Brian highlights is applying energy-dense bulk storage alongside the high-transient, high-cycle-life performance of power-dense elements such as supercapacitors and ultracapacitors. Much faster charge times address range anxiety, and so does the increased monetisation of assets through higher utilisation and peak shaving, also known as load smoothing. These benefits are now being recognised as a value-add in the AI data centre space race, alongside applications in e-mobility and robotics.

Power electronics make it work

Wide-bandgap semiconductors, GaN and SiC, have enabled power switches that address every SWaP-C factor, cost included. Gains in density, efficiency and thermal performance have pushed power electronics deeper into the system hierarchy. Integrated motor drives let a smaller, lighter supply sit directly on the motor it sources, mitigating distribution losses and transient disturbances. Grid-tied inverters now contribute virtual inertia. Brian calls power electronics “the difference-making enabler” of the mobility, robotics and AI-powered revolutions under way.

Small power supports big power

Ultra-low-power electronics have growing value in this space. Trading wires for reliable wireless links is an intrinsic win for untethered systems, and the value multiplies once those links carry telemetry. Conditional monitoring and preventative maintenance protect very expensive CapEx and extend the performance of deployed assets at lower OpEx. Perpetually self-powered sensor networks that harvest energy from their surroundings point towards systems designed to run indefinitely, and reliability improves as failure-prone components such as electrolytic capacitors, connectors and wiring drop out of the design.

What this means at the bench

Any mobile system needs sound design assumptions about the energy available and the characteristics of its battery’s discharge curve. That implies well-understood characterisation of the storage under system-specific loading, across cycle life and the full operating environment. Equivalent series resistance is likely to look very different at the extremes of the discharge curve, and it plays into usable range, cycle life and ultimate system reliability and lifetime calculations. Improved thermal performance brings a further SWaP-C benefit by reducing the need for the larger, more expensive and energy-intensive heat-mitigation hardware otherwise required.

The bigger picture

Everything above sits under the umbrella of smart mobility. Factory robotics, humanoids and AI-powered e-mobility are changing everyday business and work on the ground, and Brian is direct about the impact: some blue-collar roles, such as pick-and-place warehouse work, are supplanted by robots performing the job function. His case is that smart mobility can transition entire workforces into the next generation of industrial workers operating in concert with the technology, reaching levels of operational efficiency that were previously out of reach. Conditional monitoring and asset tracking automate oversight of expensive CapEx while optimising OpEx. He closes by looking ahead to Energy Efficiency Day in the US on Wednesday 7 October 2026, and to how much new energy awareness and enlightened consumption have already released from existing mobility footprints.