DUBLIN, Jan 13 (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.