Lord Oxburgh is so concerned at the potential destruction from global warming that he wants to devote more of his time to cutting greenhouse gas emissions and the use of fossil fuels.
The move is likely to cause some embarrassment at Shell, one of the biggest oil and gas producers in the world.
Despite a history of environmental controversies, it is now seen as one of the greenest oil companies, but each year its worldwide activities and products still release about 700m tons of carbon dioxide into the atmosphere.
By contrast, emissions from the whole of Britain total around 560m tons out of a total world output of 25 billion tons.
Oxburgh, who chairs Shell as a non-executive, said: “When I leave I would like to go onto the board of a climate change charity. I would be campaigning for more responsible use of hydrocarbons.”
Oxburgh, who is also chairman of the House of Lords science and technology committee, emphasises that the target of such campaigns would not be so much the oil companies as government ministers and departments.
He believes it is only through taxation, regulation and new technology that the world can have any hope of reducing greenhouse gas emissions.
However, his belief that governments should impose higher taxes on aviation fuels, petrol, oil, gas and other hydrocarbons to discourage their use may alarm other oil company executives.
Oxburgh, an academic geologist by training, became chairman unexpectedly last year after the forced departure of Sir Philip Watts, who was criticised in the controversy over the overstating of Shell’s oil reserves. The peer has now reached retirement age and is due to leave this summer.
He has faced apparent contradictions in chairing Shell — for example, by accepting long ago scientific arguments that the climate was being changed by greenhouse gas emissions. This has prompted him to abandon the executive transport and car park offered by Shell and adopt a folding bicycle, which he keeps in a cupboard in the lobby of the Shell building on the South Bank in London.
At home, Oxburgh has persuaded his wife and son to use bicycles and abandon the car “except for trips to the supermarket”. For those, he uses a diesel capable of 60 miles to the gallon.
“Domestically we all ride bicycles and use the car as little as we can,” he said. The family has also abandoned air travel for holidays — though Oxburgh still regularly has to fly on business matters.
His Cambridge home, insulated and double-glazed, is now also fully equipped with energy-saving light bulbs. “I have some struggles with my family; there is a little resistance because they take a little while to warm up,” he said.
Oxburgh has also helped Shell worldwide to adopt similar measures. The company now carries out carbon audits, employs consultants to seek new ways of cutting energy use and has drawn up long-term plans to reduce greenhouse gas emissions from its internal activities.
However, environmentalists say such measures are trivial when Shell is continually expanding its operations. Tony Juniper, director of Friends of the Earth, said: “Before he leaves, Lord Oxburgh should be trying to change Shell. The company is pumping more oil and gas than ever before.”
Oxburgh’s ambition was, however, welcomed by Greenpeace, which has a long history of clashes with Shell, most famously when it successfully campaigned against the company’s attempts to dump the disused Brent Spar oil rig at sea in 1995.
Blake Lee-Harwood, director of campaigns at Greenpeace UK, said: “We would still disagree on many issues but his expertise and experience would make him a welcome addition to the team.”