ExxonMobil Sanctions Longtail, Its Eighth Project Offshore Guyana

ExxonMobil has taken the final investment decision on Longtail, its eighth development in the Stabroek block offshore Guyana, after securing the required government and regulatory approvals, the company’s operating unit said on November 13. The project will tap the Longtail, Tripletail and Turbot gas and condensate discoveries in the southeastern part of the block, using a new floating production, storage and offloading vessel designed to process 1.2 billion cubic feet of gas a day and produce up to 250,000 barrels of condensate a day, with first production targeted for 2030.

Guyana’s first dedicated gas project

Longtail differs from the seven Stabroek developments that preceded it. Liza Destiny, Liza Unity, Prosperity and One Guyana — the FPSOs now in service — were built primarily to produce crude oil, with associated gas reinjected or used to fuel the vessels. Longtail is designed around non-associated gas: reservoirs where gas, not oil, is the primary resource. ExxonMobil Guyana has said the new FPSO will carry the largest gas-handling facility yet installed in the Stabroek block, with roughly 45 subsea production and injection wells feeding it. Early production is expected to reinject much of the gas to maintain reservoir pressure and maximise condensate recovery, a technique already used on other Stabroek fields.

The gas itself has a use beyond condensate recovery. ExxonMobil’s FID statement notes that some of it could eventually be piped to shore, subject to separate investment decisions, market demand and the build-out of onshore infrastructure — a reference to Guyana’s ambitions to use Stabroek gas to fuel domestic power plants and industry rather than exporting all of it as oil-linked condensate.

Who holds what in Stabroek

ExxonMobil Guyana Limited operates the block with a 45% interest. Hess Guyana Exploration Ltd holds 30% — a stake that now sits inside Chevron‘s portfolio following Chevron’s roughly $53 billion acquisition of Hess, completed in 2024, which made the Stabroek position one of the most closely watched assets in that deal. CNOOC Petroleum Guyana Limited, a unit of China’s state-owned offshore oil major, holds the remaining 25%, giving Beijing a direct stake in one of the world’s fastest-growing oil provinces.

“Longtail represents the next phase in realizing the full potential of [Guyana’s] resources,” ExxonMobil Upstream Company President Dan Ammann said in the FID announcement, adding that the project “unlocks new value” for the country. ExxonMobil did not disclose the project’s capital cost. Earlier reporting on the Longtail development, before FID, had pointed to a cost estimate in the region of $12.5 billion and a front-end engineering contract awarded to SBM Offshore for the FPSO, with the option to convert that work into a full build contract.

A fast-maturing basin

Stabroek has gone from first discovery, in 2015, to roughly 900,000 barrels of upstream oil output per day today from four producing FPSOs — a buildout pace with few parallels in the industry. ExxonMobil expects that figure to climb further as its fifth project, Uaru, ramps up output in the fourth quarter of 2026, a milestone the company says should push total Stabroek production above 1 million barrels a day. Whiptail, the sixth project, is due to start up in 2027, and Hammerhead, the seventh, in 2029. Longtail, as the eighth, is now scheduled for 2030, which would give Guyana eight producing developments in a single offshore block within roughly a decade of first oil.

That pace has reshaped Guyana’s economy. Oil revenue now funds a large share of government spending through the country’s Natural Resource Fund, and Guyana has posted some of the highest GDP growth rates of any economy over the past five years as Stabroek output has scaled. Longtail’s shift toward monetising gas, rather than oil alone, points to the next phase of that transformation: using associated and non-associated gas to cut Guyana’s reliance on imported fuel for power generation, an option the government and ExxonMobil have both flagged as the broader Stabroek development plan matures.

Sources

• Offshore Energy, “ExxonMobil reaches FID on eighth project offshore Guyana,” November 13, 2026 — FID confirmation, well count, FPSO specifications, partner stakes, Dan Ammann quote, project timeline. Link
• OilNOW, “Exxon’s Longtail to feature largest gas handling facility in Stabroek Block, targets 250,000 b/d of condensate” — independent confirmation of condensate target and non-associated gas design. Link
• OilNOW, “ExxonMobil’s Longtail project to tap three gas fields offshore Guyana” — background on the Longtail, Tripletail and Turbot discoveries. Link

Illustrative image. Photo: GuavaTrain, CC0, via Wikimedia Commons — source