Aid agencies are wasting £100 million a year on gas-guzzling 4x4s they do not need, according to a review of humanitarian operations around the world.

Charities such as Oxfam, Save the Children and Médecins Sans Frontières could divert millions of pounds of donor money from their vehicles to people who need food, medicine and water, according to the findings.

Better management would also substantially reduce carbon emissions, said Rob McConnell, co-ordinator of Fleet Forum, which counts more than 40 charities, United Nations agencies and donor groups among its members.

“We can’t use a Toyota Prius to run around in southern Sudan but we do need to analyse more carefully the type of vehicles we are using,” said Mr McConnell. “Do we need a Toyota Land Cruiser for running around Nairobi, for going to meetings or picking up mail? Could we do it in a more efficient, smaller car? Do we have too many vehicles?”

The answer for many residents of the Kenyan capital is a resounding “yes”. The city is a hub for aid operations in East Africa with offices monitoring emergencies in Somalia, Sudan and the Democratic Republic of Congo, among others.

As a result the giant 4x4s – most frequently a Toyota Land Cruiser but often a Nissan Patrol or Mitsubishi Pajero – are a common sight.

In the evenings such vehicles, decked out with UN or charity logos and equipped with bull-bars and radio antennae, clog supermarket car parks or block restaurant driveways as their drivers try to manoeuvre into tight spaces.

But there is a more important price to pay. Mr McConnell says that his members run 70,000 vehicles, of which half are hardcore off-roaders, with an operating cost of £500 million each year. In all they pump 500,000 tonnes of carbon in the air.

At any time, a third of the fleet is immobile, which places another drain on resources that could be better spent, according to research by Jacana, a logistics company.

Better management of the vast fleet – such as monitoring performance, buying cars better suited to their use and more regular maintenance – could reduce accidents, cut emissions and save £100 million a year.

Mr McConnell said that few agencies had even introduced computer management techniques.

“What we would have to do is change the way that our organisations work and I think humanitarian agencies are not exactly renowned for their ability to implement effective change management quickly and effectively,” he said.

The World Food Programme of the UN and World Vision, the world’s biggest Non Governmental Organisations, are among those that have led the way in making improvements. Catholic Relief Services has also introduced software to help to monitor the performance of its drivers and fleet of more than 1,500 cars and 1,000 motorbikes in 85 countries.

Fuel efficiency could be monitored, problems spotted earlier and vehicles repaired or sold before they fell apart, said David Coddington, deputy regional director for East Africa.

He said that several programmes were considering buying hybrid vehicles and had stopped using old and worn-out 4x4s for running around town.

“The bottom line is conserving resources,” he said. “If we have fewer accidents we save a lot of money on repairing vehicles . . . If we use less fuel then not only is it good for the environment, but we save money.”

What they cost

Nissan Patrol mpg 26.2; weight 3.2 tonnes; cost £24,395

Toyota Land Cruiser mpg 30.7; weight 2.8 tonnes; cost £27,595

Mitsubishi Pajero mpg 26.9; weight 2.7 tonnes; cost £22,649

Toyota Avensis mpg 60; weight 1.9 tonnes; cost £14,495 (all diesel models)

Sources: Mitsubishi, Toyota, Nissan

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