By Arathy Somasekhar

HOUSTON, Aug 21 (Reuters) - U.S. crude oil export gains

should plateau in 2024 after years of strong growth, with

domestic output expected to increase by the smallest amount

since the pandemic at a time when global oil demand remains

sluggish.

Crude oil exports from U.S. ports averaged about 4.2 million

barrels per day so far this year, according to U.S. government

data. That was up 3.5% from a year earlier, or the lowest

percentage increase since 2015, when the U.S. exported its first

cargo of domestic crude oil after a 40-year federal ban on

export of domestic crude ended.

Last year, exports grew 13.5%. They have grown every year

except in 2021 when COVID-19 crushed global oil demand.

"U.S. crude exports are plateauing due to a combination of

slowing supply growth and easing demand - particularly from Asia

this year," said Matt Smith, an analyst at energy data firm

Kpler.

U.S. oil production is set to grow just 2.3% this year, as

shale producers remain focused on shareholder returns and limit

new spending on production.

Offshore production is expected to rise this year on new

project startups, such as Chevron's ( CVX ) Anchor platform in the Gulf

of Mexico. But output is expected to ramp slowly over several

years, meaning exports this year will not benefit.

Global demand for oil has slowed this year, especially in

China, where a protracted property downturn has exacerbated

economic worries. Average U.S. daily exports of crude oil to

China has fallen by more than a third so far this year, data

from Kpler showed.

The recent expansion of Canada's Trans Mountain pipeline has

also boosted China's imports of crude directly from that

country's west coast. Previously, Canadian crude was transported

to the U.S. Gulf Coast and exported from there to China.

U.S. export volumes to Singapore also fell, while those to

India and South Korea climbed.

"Asia demand has not materialized," said Rohit Rathod,

market analyst at energy researcher Vortexa.

Average daily U.S. exports to Europe also edged down about

1% so far this year versus last year as European buyers bought

cheaper regional and West African oil.

The only major new market for U.S. crude has been Africa, as

Nigeria's Dangote refinery snapped up barrels of WTI Midland

crude after its start up early this year.

"Dangote is an outlier when it comes to new refining

capacity, in that it is running on predominantly light sweet

crude - from Nigeria or the U.S.," Kpler's Smith said.

"New refining capacity is being built predominantly in OPEC+

countries or Asia, two regions where light and medium sour

barrels are more prevalent," Smith added.

U.S. export volumes could get a boost in coming weeks on

production constraints in Libya and elsewhere, and as U.S.

refiners start maintenance, pushing more domestic barrels onto

the water.

Refiners that usually import light sweet crude could look to

replace Libya's Sharara with U.S. WTI Midland among other

grades, trade sources said, after Libya's National Oil

Corporation declared force majeure on the Sharara field from

Aug. 7.