* Shell boss says oil prices to remain volatile in 2015
* Van Beurden urges oil sector to take lead in climatedebate (Adds quotes, details)
By Ron Bousso
LONDON, Feb 12 (Reuters) - The head of Royal Dutch Shell expects global oil supplies to fall behind demandgrowth as the recent halving of crude prices forces companies tocut production.
In excerpts from a speech Shell Chief Executive Ben vanBeurden is to give at the International Petroleum Week dinner onThursday evening, he said he expected oil prices to remainvolatile in 2015 as the market struggles to find a balance.
"Seeing today's prices, supply will probably not keep pacewith this growth. It may even decline, as prices are close tocash costs, according to consultants like Wood Mackenzie," vanBeurden said.
As projects are postponed and cancelled around the world dueto the low oil prices, new supply could fall in 2 or 3 years,failing to catch up with the expected economic growth.
"The market could tighten quickly," he said.
But at the same time, if U.S. shale oil production, the maindriver of the rise in global oil supplies in recent years,proves resilient in the face of the lower prices, the oil pricerecovery could take longer.
"Either way: The market will remain volatile in 2015, ifonly because for now, OPEC shows no sign of wanting to resumeits role as swing supplier," van Beurden said.
Oil prices have halved to around $55 a barrel sincelast June. Prices took a sharp dip after the Organization of thePetroleum Exporting Countries (OPEC) decided not to cut outputin November.
Most major oil companies have slashed exploration spendingin 2015 by more than 10 percent compared to last year as theyadjust to the low-price environment.
Shell, the largest European energy major, announced arelatively modest three-year, $15 billion cut in potentialspending last month as van Beurden warned against over reacting.
CLIMATE DEBATE LEADERS
In his speech, van Beurden urged the oil and gas sector totake a leading role in the fight against climate change tointroduce "realism and practicality" into the debate.
While criticising peers for not being vocal enough overenvironmental issues, van Beurden rejected the idea thatrenewable energy can replace fossil fuels fully as the world'spopulation grows and with it demand for energy.
"Yes, climate change is real. And yes, renewables are anindispensable part of the future energy mix. But no, provoking asudden death of fossil fuels isn't a plausible plan." (Reporting by Ron Bousso. Editing by Jane Merriman)