Shutterstock Save for later Print Download Share LinkedIn Twitter Oil companies are naturally keen to get the most out of their kit to bolster development economics and lower unit costs. But Exxon Mobil’s debottlenecking successes offshore Guyana are adding substantial production capacity in the already prolific deepwater province.Exxon and partner Hess said during their respective earnings calls last week that the floating production, storage and offloading (FPSO) units serving their Liza Phase 1 and Phase 2 developments achieved record combined output last quarter of 380,000 barrels per day, or nearly 12% above their joint nameplate capacities.The additional 40,000 b/d is in itself a nice fillip for the Stabroek Block, which is also held with China National Offshore Oil Corp. But the US partners said there is more to follow, with further efforts expected to lift combined capacity above 400,000 b/d — roughly one-fifth higher than the projects were sanctioned to produce.“I can't say enough about the outstanding job they're doing as an operator,” Hess E&P head Greg Hill said of Exxon.FPSO SubstituteThe additional barrels are more than just a cherry on top for one of the industry’s fastest deepwater frontier developments on record.With Exxon expecting to replicate the results at its third FPSO coming on line next quarter and hoping to continue those gains across the string of future FPSOs planned for the block, the consortium could potentially eke out the equivalent of an entire additional FPSO without sinking another well or fronting the billions in capex a new development would require.“Frankly, the expectation that we have for ourselves is that as we ... go forward and continue to build these projects, we'll continue to find the same kind of benefits and optimization opportunities,” Exxon CEO Darren Woods told analysts. “And it comes back to this inherent capability that we've built into our businesses.”The US major and its partners have line of sight on at least six FPSOs by 2027 with a combined nameplate capacity exceeding 1.2 million b/d. Up to four additional FPSOs could be considered after that.But even with such an aggressive development schedule, there are big benefits to bumping up output across those FPSOs as they come on line.The Stabroek block boasts more than 11 billion barrels of oil equivalent of recoverable reserves and continued exploration could bump that figure even higher. But with uncertainty surrounding the long-term trajectory of global oil demand, bringing forward every barrel as quickly as possible helps ensure they will see the light of day. Indeed, the debottlenecking efforts come amid a wider oil industry push toward more “just-in-time” supplies that can minimize lead times and help mitigate the tail risk surrounding demand. Stabroek Developments ('000 b/d)StatusNameplate CapacityProjected Capacity Liza Phase 1Operational120150 Liza Phase 2Operational220250+ PayaraStart-up Q4'23220-- YellowtailStart-up 2025250-- UaruStart-up 2026250-- FPSO No. 6Start-up 2027---- FPSO No. 7-10Start-up 2027+---- Source: Energy Intelligence, Exxon Mobil and Hess commentary Getting the Job DoneWoods credited Exxon’s integrated project development organization for its successes off Guyana, with initial facilities specifically designed to support future incremental investments as the surrounding resource merits.“The mindset in the company is once you get steel on the ground, you've got this capital; the operations job is to run it reliably, run it safely, run it in an environmentally responsible way, but at the same time, maximize the value of that steel in the ground,” he said.Woods said the debottlenecking gains on the Guyana FPSOs came from “a lot of little things” rather than one standout upgrade or improvement.While neither Exxon nor Hess have revealed the costs associated with this debottlenecking program, the baseline break-even costs for the initial capital sunk into the first five FPSOs ranges between $25-$35 per boe, making these some of the most attractive oil barrels around.