Battery Payload Loss: What the RHA Debate Reveals About Electric HGV Economics
Battery payload loss has become one of the clearest real-world constraints on battery-electric HGV deployment at 44 tonnes. The RHA Payload Loss Survey Report, and the debate it triggered, make one point increasingly hard to avoid: for the heaviest long-haul freight, payload loss is not a marginal issue but a structural economic one.
Summary
The Road Haulage Association’s March 2026 Payload Loss Survey Report gives the most useful operator-led dataset yet on how battery weight affects commercial viability in heavy freight. The central finding is simple: at 44 tonnes, electric HGVs lose enough payload that many fleets cannot replace diesel one-for-one without adding more vehicles, more drivers, and more journeys.
The online debate that followed raised sensible questions: how many loads are really full, isn’t volume more important than weight, won’t better batteries solve this, and could autonomous driving or smoother operation offset the penalty? These are all worth answering properly, because they go to the heart of whether battery payload loss is a temporary issue or a structural one.
Key Takeaways
- A 44-tonne electric 6×2 tractor carries about 3,345 kg less payload than its diesel equivalent, an 11.8% payload loss.
- The current two-tonne derogation does not apply to the six-axle 44-tonne articulated combinations that dominate UK long-haul trunking.
- The RHA survey shows that only 37% of operators above 42 tonnes believe they could meet all their delivery requirements within a 22-tonne payload.
- Battery improvements help, but the projected reduction in battery mass by 2040 is not enough to eliminate the current payload penalty.
- Autonomous driving may improve energy efficiency, but it does not reduce battery mass or restore lost payload.
Main Analysis
The core of the battery payload loss issue is easy to state. If the truck gets heavier and the gross weight limit stays the same, payload falls. That is what the RHA quantified using real operators and sample vehicle comparisons. In the report’s headline Volvo comparison, the electric 6×2 tractor weighs 11,490 kg versus 8,145 kg for the diesel equivalent. With the same 44,000 kg gross weight limit and a standard 7,500 kg trailer, payload falls from 28,355 kg to 25,010 kg.
That 3,345 kg reduction is not just a technical curiosity. It means fewer tonnes moved per journey, more journeys to move the same annual volume, and higher costs across fuel, labour, tyres, maintenance and asset utilisation. The RHA estimates that running an electric 44-tonne 6×2 costs £28,282 per year more than diesel on the assumptions used in the report, rising to an 18.7% increase in total operating cost once the additional journeys required to compensate for payload loss are included.
This matters because the UK freight market is not short of light-duty use cases where battery-electric works reasonably well. The problem sits in the heavy end of the market, where operators are running above 42 tonnes and where dense freight flows dominate. That is also why this discussion fits directly with my earlier work on zero-emission HGV total cost of ownership, the UK policy gap on zero-emission HGVs, and the real-world fleet TCO calculator that explicitly includes payload loss rather than assuming one-for-one substitution.
What Percentage of Loads Are Actually “Full”?
This is the most common objection, and it sounds reasonable until it is framed correctly. The right question is not really how many loads are at maximum diesel capacity. The better question is how many loads exceed the electric payload limit of 22 tonnes, because that is the threshold that determines whether a 44-tonne electric truck can do the job without additional journeys.
The RHA survey addressed this directly. Of operators running above 42 tonnes, 40% said fewer than a quarter of their deliveries could be fulfilled within 22 tonnes. 57% said fewer than half could be fulfilled within 22 tonnes. Only 37% believed they could run their whole operation within that payload limit. That tells you much more than a generic “average load” number does.
The report also gives an average outbound load of 20 tonnes. That figure is often cited as evidence that the problem is overstated. But averages hide tails. A 20-tonne average does not mean the majority of economically important loads are safely below 22 tonnes. It means that lighter jobs and heavier jobs are being compressed into a single number. The RHA’s own operator responses suggest that roughly a third of journeys by volume, and a large share of the heaviest commercial work, sit above the electric ceiling.
It is also worth noting that the 20-tonne figure covers outbound loaded legs only. It does not include empty running. If you averaged across all movements, the average would fall further, but that would not make battery-electric more viable. It would simply make the 22-tonne threshold look even tighter relative to the subset of journeys that actually generate revenue.
Is Volume More Important Than Weight?
Sometimes yes, but not in the segment the RHA is mainly describing. In parcels, e-commerce, some automotive flows and parts of retail distribution, trailer cube can be the binding constraint. In those cases, a 22-tonne electric payload may well be workable, and battery-electric trucks can make commercial sense if range and charging are manageable.
For 44-tonne artics on long-haul trunking, however, operators typically hit weight before they run out of space. These are dense flows: food, retail bulk, palletised freight, aggregates, and other high-mass applications where trailer volume is not the first constraint. In that world, taking 3.3 tonnes out of usable payload is a hard economic penalty, not a niche edge case.
This is why the RHA operator responses matter. If volume were usually the dominant limit at 44 tonnes, then a lower electric payload ceiling would not cause such a sharp operational problem. Instead, the survey shows that for a large share of operators above 42 tonnes, the 22-tonne limit rules out a significant part of their delivery profile. That is strong evidence that weight, not cube, is the practical constraint in the duty cycles the report is concerned with.
I covered this broader mismatch between policy assumptions and fleet reality in Zero Emission HGVs UK: The Policy Gap, which looked at how payload loss, infrastructure and cost stack together for actual operators rather than in generic roadmap diagrams.
Will Battery Improvements Offset Battery Payload Loss?
This is the strongest argument in favour of patience: batteries will get better, so the weight penalty will shrink over time. That is true in part. Energy density is improving and battery packs will continue to get lighter for a given range. But the key question is whether those improvements are large enough, and early enough, to remove the commercial problem in heavy trucks.
The RHA report cites analysis suggesting batteries may be around 20% lighter by 2040. That is helpful, but it does not close the current gap. If a long-range truck battery pack weighs around 4,500 kg, a 20% reduction saves roughly 900 kg. The payload gap identified by the RHA is 3,345 kg. Even after those improvements, the operator is still carrying more than two tonnes of extra mass compared with the diesel baseline.
This is broadly consistent with the argument I made in Battery Energy Density 2025: State of the Art & Next-Gen Tech. Battery energy density has improved dramatically over the past three decades, but the sector is now in the phase of harder, slower incremental gains rather than repeated order-of-magnitude jumps. For heavy trucks, those incremental gains help range and efficiency, but they do not eliminate the payload penalty on the policy timescales that matter.
That is why battery improvement alone is not a sufficient answer to battery payload loss at 44 tonnes. Either the regulations change, the duty cycle changes, or the powertrain changes.
Will Autonomous Trucks or Better Driving Styles Solve the Problem?
Autonomous trucks, platooning and smoother driving styles all improve energy efficiency. They can reduce electricity or fuel consumption per mile, which matters, especially when power costs are high. But they do not make a heavy battery pack disappear.
The RHA’s payload penalty is driven by the physical mass of the battery and the fact that current UK gross and axle weight rules do not adequately compensate for it at 44 tonnes. More efficient driving can reduce cost per mile, but it does not restore the missing 3,345 kg of payload. If the truck still weighs more, it still carries less freight at the same gross weight limit.
So autonomy may improve operating economics around the edges. It does not remove the core battery payload loss problem. Unless you pair it with regulatory change or a different energy storage technology, the fleet still needs more journeys to move the same tonnage.
Why This Matters for Operators, Policymakers and Technology Developers
For operators, the significance of battery payload loss is straightforward. If payload falls, fleet economics deteriorate, contract structures come under pressure, and service models need to change. That is why tools such as the Real-World Fleet TCO Calculator and the Commercial Fleet TCO Calculator need to account explicitly for payload-sensitive operations.
For policymakers, the issue is equally clear. The RHA is not arguing against decarbonisation. It is arguing that the current framework creates a structural disadvantage for zero-emission vehicles in the heaviest part of the market. The association’s proposed response is targeted: raise the gross vehicle weight for affected electric HGVs from 44 to 46 tonnes, lift the drive axle limit from 10.5 to 12.5 tonnes, and review length and turning-circle constraints. Industry reporting and the RHA’s own materials make clear that this is intended as a practical fix to a practical problem, not a general deregulation of heavy vehicles.
For technology developers, the lesson is that product-market fit in freight depends on operational reality, not just engineering performance. Battery-electric trucks remain well suited to some freight tasks. But in the top-weight segment, the payload penalty creates a commercially important gap that alternative powertrains may address more effectively. That is one reason I continue to compare battery and hydrogen options in pieces such as Zero-Emission HGV TCO: Hidden Costs Battery vs Hydrogen Trucks and Hydrogen vs Battery-Electric by 2030.
Closing Insight
The interesting thing about the RHA payload-loss debate is not that it has generated disagreement. It is that it has forced the disagreement onto quantifiable ground. Once the question becomes “how many loads exceed the electric limit?” rather than “are trucks ever full?”, the shape of the problem becomes much clearer.
Battery payload loss is not an argument against battery-electric freight. It is an argument against assuming that the heaviest freight segments can decarbonise on the same terms as lighter ones. If policy ignores that distinction, operators will respond rationally: they will delay investment, look for alternatives, or stay on diesel longer than anyone intended.
Related Reading
External Sources
FAQ: Battery Payload Loss
What is battery payload loss?
Battery payload loss is the reduction in usable freight capacity caused by the extra mass of the battery-electric powertrain. At a fixed gross vehicle weight, a heavier tractor means less cargo can be carried.
Why does battery payload loss matter for electric HGVs?
It matters because freight economics depend on tonnes moved per vehicle and per driver. If an electric truck carries materially less payload than diesel, operators need more journeys, more vehicles and more labour to move the same amount of freight.
Can better batteries remove the payload penalty?
They can reduce it, but current projections do not suggest they will eliminate it quickly enough to solve the 44-tonne problem under existing UK rules.
Is weight really a bigger issue than volume?
In some freight segments volume is more limiting, but in the 44-tonne long-haul articulated segment studied by the RHA, weight appears to be the more important commercial constraint.
Will autonomous trucks solve battery payload loss?
No. Autonomous operation may improve efficiency and lower energy cost per mile, but it does not reduce the mass of the battery pack or restore lost payload.
If this connects with something you are working on, send me a note. I am interested in serious conversations around hydrogen, batteries, infrastructure, advanced materials and deep tech commercialisation.
