Four out of five businesses do not measure the carbon emissions of employee-owned vehicles used for business purposes, according to a new survey.

Commissioned by Trimble Field Service Management and carried out by Sewells Research and Insight, the survey also found 80% of respondents felt that it would be more beneficial to monitor their fleets more closely, while 46% said they were looking at limiting the mileage of their grey fleets.

Eliminating grey fleets completely is certainly not on the agenda, as 92 percent reported that this was not an option for their businessThe environmental impact of this grey fleet, which according to some reports accounts for about 4m vehicles on UK roads, is significant and offers an untapped opportunity to measure and manage emissions.

The study also reveals that almost a third of companies with grey fleets do not even record the mileage of these vehicles.

Many of the businesses that do monitor mileage will base calculations simply on expense claims, as opposed to a more accurate measurement. Therefore a significant number may be failing to utilise this information in order to make cost or green improvements.

Mark Forrest, general manager of Trimble’s Field Service Management division, said: "For any business that runs an operational fleet, managing emissions and on-the-road costs is a top priority. Many businesses are already utilising fleet management and telematics to manage fuel use and organisations with grey fleets can look to borrow from this knowledge and experience.

"With the survey finding that many UK businesses appear to be ignoring the effects of their grey fleets, there is a real impact not only from an environmental perspective but from an operational expense standpoint as well.

"As the price of fuel continues to rise and environmental concerns heighten, a huge number of vehicles on UK roads that are being used for business purposes are effectively ‘driving blind’. The ability to manage vehicle mileage and CO2 outputs for fleet vehicles has delivered significant reductions in fuel use for businesses and has contributed to their sustainability goals, and it is encouraging to see that the survey shows there is both the opportunity and appetite to replicate this in the grey fleet market.”.