Investing.com -- US ethane prices have risen 20% month-to-date and 33% since the end of July, according to BMO Capital Markets. The increase outpaces US natural gas markets, where Henry Hub prices gained 3% month-to-date and 12% over the same period.

BMO's energy team identified several factors driving the ethane price increase. The Chevron-Qatar Golden Triangle plant's ethane cracker is expected to begin commissioning in late 2026 and ramp up in 2027. The facility may be drawing on markets to add storage and fill pipelines ahead of its expected 110,000 barrels per day consumption when operational.

Enterprise and Energy Transfer expanded their Gulf Coast ethane export capabilities by approximately 550,000 barrels per day in the past 12 to 18 months, BMO said. About 430,000 barrels per day of this capacity can switch between LPG and ethane, with most expected to flex toward ethane.

Five very-large ethane carriers were delivered since May, bringing the 2026 total to 11 vessels compared to a fleet of 40 in 2025. Two additional vessels are scheduled for delivery late this year. According to East Daley, 21 more vessels are planned for 2027, which would increase total global ethane shipping capacity to 7.61 million cubic meters from 5.13 million cubic meters in 2026 and 4.04 million cubic meters in 2025.

International flex crackers have increased ethane use, potentially responding to the longer-term strip showing 2027 WTI-Brent at $86-$94 per barrel, BMO noted.

CMA recently forecast ethane cash production costs to rise 9% in 2027, or 6% from current levels. BMO said the US producer advantage may decrease for Dow (NYSE: DOW), LyondellBasell (NYSE: LYB), and Westlake (NYSE: WLK).