A new RHA report suggests the biggest barrier to electric HGV uptake in the UK is not only range, but payload loss caused by current weight, axle and dimensional rules. Its findings show that many deliveries could be completed by electric trucks in principle, but far fewer can be done efficiently when 44-tonne operations lose too much payload compared with diesel equivalents.
Here are the key findings:
- 74% of deliveries could be completed by an electric HGV if charging is available at the destination
- 51% of deliveries could be completed if the truck must return to base to recharge
- 57% of operators said they could complete less than half of their deliveries with a 22-tonne payload
- 11.8% payload loss on the electric 44-tonne 6×2 examined by the RHA, compared with its diesel equivalent
For years, the debate around electric lorries has focused on battery range. The RHA’s latest report shifts attention to a different constraint: the amount of freight those vehicles can legally carry once battery weight is factored in. The association argues that current UK regulations are creating a “structural barrier” that makes electric HGVs less efficient and more expensive to operate in heavy-duty work.
The report, based on responses from 114 operators, found that 74% of deliveries could be completed by an electric HGV with a 300-mile range if charging is available at the delivery point. But that figure falls to 51% if the vehicle has to return to base to recharge. That points to a clear split between what is technically possible on paper and what works in a real operation without wider charging access.
The two-tonne allowance still leaves the heaviest trucks exposed
The UK already allows a two-tonne derogation for certain zero-emission HGVs to account for heavier batteries, but the report says that this does not solve the problem for the heaviest 44-tonne articulated lorries. That is why the RHA is now calling on the government to raise the authorised gross weight for electric HGVs from 44 to 46 tonnes, increase the drive axle limit from 10.5 to 12.5 tonnes, and convene a technical working group to review the wider rules.
This matters because the operators most likely to electrify heavy haulage are also the ones most exposed to the gap in the regulations. According to the survey, 88% of respondents operate vehicles above 42 tonnes, and only 37% of those affected said they could still meet their requirements within a 22-tonne payload.
The report also found that 57% of operators could complete less than half of their deliveries with that payload. In practice, that means more trips are needed to move the same freight. Once that happens, the claimed operational gains of electrification start to weaken very quickly.
The penalty shows up in the cost base
To quantify the impact, the RHA compared Volvo diesel and electric tractor units and modelled the annual running cost gap, including both energy costs and the extra cost created by additional journeys.
Its calculation found that an electric 44-tonne 6×2 costs £28,282 more per year to run than the diesel equivalent. For an electric 40-tonne 4×2, where the current derogation does apply, the additional annual cost falls to £15,738. The report says that if payload parity were achieved, those extra costs could be reduced by £16,201 and £5,492 respectively.
The payload gap behind those figures is significant. In the 6×2 example used by the RHA, the electric vehicle loses 11.8% of payload versus diesel. In the 4×2 example, the gap is 4%. The report says that, where this penalty exists, operators may need up to 11.8% or 4% more journeys respectively to carry the same freight as diesel vehicles.
There is, however, a more optimistic scenario in the report. It says that if payload loss were removed and depot electricity prices fell to £0.25 per kWh, an electric 6×2 could produce an annual saving of £1,855 compared with the diesel equivalent. In other words, the report is not arguing that electric HGVs are inherently uneconomic. It is arguing that the present regulatory framework is preventing operators from reaching that point.
Gross weight is only part of the problem
The RHA also says the issue goes beyond headline vehicle weight. Feedback from dealers points to a wider set of constraints that reduce the commercial viability of electric 44-tonners.
One problem is axle load. The report says unchanged axle weight limits can prevent an operator from using the full legal gross weight of an electric HGV because one axle reaches its statutory ceiling first. Another is vehicle design: three-axle electric tractor units often need a longer wheelbase to fit enough batteries, but that can then clash with overall vehicle length rules or turning-circle requirements.
That combination of limits can make some standard trailer setups less practical and leave operators leaning back towards diesel tri-axle tractors, which still offer better payload and more familiar economics.
