DUBLIN (Reuters) - Air passengers numbers are projected to more than double by 2050, boosting fuel demand and undermining the aviation industry's efforts to cut emissions, a study by climate advocacy group Transport and Environment suggested on Monday.

As industry leaders meet at an annual finance conference this week in Dublin where many plane sales are expected, the Brussels-based group urged the European Union to take steps to rein in the sector's growth.

"It's time to come back down to earth and put an end to this addiction to growth," Jo Dardenne, the group's aviation director, told Reuters.

Steps to tame fast-growing air travel could include limiting airport infrastructure growth and corporate travel while increasing taxation, the report said.

The airline industry, which generates about 2.5% of global carbon emissions, has vowed to use more sustainable aviation fuel (SAF) in a bid to reduce emissions and reach net zero by 2050.

But scant supply and prices up to five times higher than traditional jet fuel mean little of the greener fuel is used.

Monday's report said industry fuel use was forecast to rise 59% by 2050 from 2019 levels as passenger numbers increase.

With plane makers Airbus and Boeing ( BA ) projecting high growth in coming years and more planes in the sky, emissions are set to increase, despite more efficient jets and use of SAF.

"The more they grow, the further away they move from it," said Dardenne. "At this rate, they will still be burning two billion barrels of oil per year in 2050, despite using SAF."

Airbus and Boeing ( BA ) did not respond to a Reuters request for comment.

The industry has repeatedly rebuffed calls to curtail growth, saying the sector is essential to economic development and global connectivity.

"Instead of speculative and selective projections decades into the future, the focus should be on implementing tangible solutions today," a spokesperson for trade body Airlines for Europe told Reuters in response to the report.

Such solutions would lower the impact of aviation and preserve benefits, the spokesperson added.