The company said it had come under particular criticism for forecasting a 20% residual value for the Azure Dynamics Transit Connect Electric last year. But added that this was sensible, based on feedback from those within the industry.

Canada-based Azure Dynamics has recently halted its European operations while it files for financial protection, and electric van manufacturer Modec, based in Coventry, folded last summer. CAP also pointed out recent research by Element Energy, which showed significantly higher total ownership costs for an electric van.

Residual values are also complicated because of rapid advances in battery technology. Another Element Energy report forecasts a 50% cost saving and 30% mass reduction for EV batteries, which could make existing vehicle technology obsolete, the company said.

Tim Cattlin, monitor editor for CV's at CAP, explained: ‘At last week’s Fleet World EV and Low CO2 Fleet show held at Silverstone the consensus from speakers in the seminars seemed to be that the alternative fuel industry, both car and CV, urgently needed some early adopters to buy in to the principle.

‘There is still much real world scepticism amongst fleet managers and operators who are reluctant to set sail into uncharted waters and whilst this sentiment exists it is also likely that those involved in forecasting and setting residual values will continue to exercise great caution.’