Thailand’s PTT Exploration and Production (PTTEP) and its partner Valeura Energy have agreed to proceed with the first development phase of the Bussabong field, located within Block G3/65 offshore the Gulf of Thailand.
PTTEP is participating in the project through its subsidiary, PTTEP Energy Development.
The decision marks the final investment decision (FID) for the project and is the first organic gas development in the Thailand portfolio of Canada-based Valeura.
PTTEP operates both the Bussabong field and the neighbouring Bongkot field.
The first stage involves installing two gas wellhead platforms, each with capacity for 24 wells.
The platforms will be linked by a nine-kilometre subsea pipeline to existing gas processing infrastructure at Bongkot.
First gas from Bussabong is targeted for the end of 2028.
Valeura estimates its capital expenditure for its 40 per cent working interest in phase one at around US$35m, covering facilities, installation and pipelines, budgeted for 2027 and 2028.
The company expects further investment of US$20 million to US$25 million for its share of drilling 25 development wells. No significant spending is planned for 2026.
Valeura president and CEO Sean Guest said the company had moved quickly since confirming its partnership with PTTEP.
“I am pleased to have rapidly turned our strategic farm-in with PTTEP into tangible development action,” said Guest.
“Within 14 months of entering into this arrangement, we are taking our first gas FID, which we believe sets us on a course to broaden and diversify our business in the Gulf of Thailand.”
Guest also pointed to the pace of the schedule ahead.
“Phase 1 is set to unfold quickly, with first gas planned for approximately the end of 2028,” said Guest.
“This quick action reflects PTTEP’s customary streamlined approach and underscores the importance of establishing this strategic relationship.”
Phase one is expected to deliver roughly 30 million cubic feet per day (mcf/d) of sales gas in 2029, rising to 40mcf/d in 2030.
Valeura’s share of that output corresponds to 12mcf/d and 16mcf/d respectively.
The gas is described as relatively dry, with around 20 barrels of condensate per million cubic feet.
The operator will work with Thai regulators and buyers to formalise the gas sales agreement.
Pricing is expected to follow the established framework for domestic gas contracts in Thailand, which typically involve long-term, take-or-pay agreements linked to a basket of commodities and adjusted for inflation.
The Bussabong field lies in the eastern part of Block G3/65 and is divided into multiple fault-block compartments, which allows for a phased approach to development.
The area has been mapped with 3D seismic data, and both historic and recent exploration wells have indicated the presence of gas, supporting the decision to proceed.
PTTEP secured the rights to explore for and produce petroleum from the G3/65 Project in 2023 through a production sharing contract, which spans around 11,647km².
Following the conditions set out in the farm-in agreement, PTTEP retains a 60 per cent stake, while Valeura Energy (Chaiyaphruek) holds the remaining 40 per cent.
The formal transfer of Valeura’s working interest has received executive approval from the Thai Government’s cabinet.
Administrative completion is expected by late September or early October 2026.
Elsewhere in its Thai operations, Valeura completed an eight-well drilling programme at the Nong Yao field, also offshore in the Gulf of Thailand, in June 2026.
