BP, the Nectar loyalty card scheme and IT supplier Atos Origin on Monday launched a five-month personal carbon credit trading trial, intended to show that such a scheme could be set up inexpensively and using current technology.

The trial, an initiative of the Royal Society for the Encouragement of Arts, Manufactures and Commerce (RSA), will be open to 1,000 volunteers.

Each consumer will be given a credit representing their allotment of carbon emissions, with units deducted from their account each time they buy petrol at a BP service station using their Nectar card.

The allotment given represents five tonnes of carbon dioxide per year, or about half the average UK citizen's lifestyle-related carbon emissions, a figure intended to illustrate the level or emissions reduction recommended by the UK government to reduce the danger of disastrous climate change.

Users will be able to monitor their units and trade units with other volunteers using an online system called CarbonDAQ.

Atos Origin designed and built all of BP's forecourt payment systems and will manage the transfer of data to the RSA's carbon trading platform.

The platform calculates the user's future carbon emissions based on the grade as well as the volume of fuel purchased.

Last month, the UK environment ministry Defra published a study examining the viability of a nationwide personal carbon trading scheme, finding that the idea would be expensive to set up and run. Set-up costs were estimated at between £700 million and £2 billion, with running costs of between £1 billion and £2 billion a year, Defra estimated.

The RSA scheme is intended to demonstrate that existing loyalty card infrastructure could be used instead of setting up a purpose-built system, which the RSA argues would slash costs.

"We are undertaking this innovative trial to understand how a personal carbon trading scheme could operate in practice, and gain some understanding about how people will interact with it, helping to take the debate about personal carbon trading forward," said Matt Prescott, director of the project at the RSA, in a statement.

The RSA argues that such a scheme is crucial, since nearly half of all UK carbon emissions relate to individual decisions.

Tim Yeo MP, chairman of the House of Commons' environmental audit committee and the Conservatives' former shadow environment secretary, supported the RSA's trial, noting in a report in the Guardian newspaper that such a scheme could be operated within the private sector.

However, Friends of the Earth reportedly responded that individuals have only a limited amount of control over carbon emissions, and that the scheme must not distract attention from the need for climate change to be placed at the heart of all government policy decisions.

The RSA will publish its first findings in November.