ExxonMobil to start-up more wells to boost full production of Liza Unity FPSO

United States oil giant ExxonMobil is looking to ramp up production on the Liza Unity Floating, Production, Storage and Offloading (FPSO) vessel four months after start-up, with the aim of realising its full capacity of 220,000 barrels per day (bpd) by the third quarter of this year.
This is after the gas compression and injection systems on the Unity FPSO were safely commissioned in what Exxon has said is around half normal industry time. According to the oil major, which along with its co-venturers is the operator of the oil-rich Stabroek Block offshore Guyana, this was done with the achievement of background flare as designed, and within the 60-day period outlined in the Liza Phase 2 Environmental Permit.
Production on the Liza Unity FPSO vessel commenced in February this year, and efforts have been undertaken to bring the operations safely online.
“The start-up period involved temporary, non-routine flaring to safely commission the production and gas compression systems,” Exxon said on Thursday. Production Manager of ExxonMobil Guyana, Mike Ryan, has also said, “This achievement is a testament to the team’s dedication to steady, safe operations. It also demonstrates ExxonMobil’s capabilities as an industry leader, and our commitment to operational excellence.”
The design of the Unity FPSO, the flagship vessel for Liza Phase 2 – Exxon’s second development project in the Stabroek Block – eliminates routine flaring by using produced gas to power the FPSO, and by reinjecting gas into the reservoir to conserve the gas and to improve oil recovery, thereby reducing emissions, compared with traditional methods.
According to Exxon, its team was also able to commission the water-injection system, which is now online and operational.
“The next step is to start up additional new wells in the ramp-up to full production of 220,000 barrels of oil per day during the third quarter,” the US oil giant noted.
Liza Unity is the second FPSO producing oil offshore Guyana, where Exxon estimates there are almost 11 billion oil equivalent barrels in the Stabroek Block alone. The Unity FPSO has a capacity to produce 220,000 bpd, nearly twice the current capacity of the more-than-120,000 bpd at the Liza Destiny FPSO, which began production in December 2019 and has experienced several bouts of above-normal flaring activities.
This had resulted in Exxon being under fire for more than a year, with environmentalists being up in arms over the harmful effects increased flaring has inflicted on the environment.

Liza Destiny’s new gas compressor
The oil company has had to send its gas compressor, on at least two occasions, for repairs in Germany, due to technical issues that caused the increased flaring and resulted in production having to be significantly reduced at one stage.
However, while Exxon was able to bring down its flaring levels with the fixed gas compressor, the company had ordered a new design that is expected to prevent such events in the future.
On Thursday, the oil major also disclosed that the new redesigned Flash Gas Compressor for the Liza Destiny FPSO has arrived in Guyana for installation, after extensive testing in Germany. The team is now working towards start-up in mid-July with the aim of also achieving background flare on that vessel as designed, it noted.
“We have relentlessly pursued a solution to this highly complex issue, and have never lost sight of that goal. We are pleased that the newly designed machine is now offshore, and the teams are methodically removing the original machine in preparation for the upgraded Flash Gas Compressor installation and startup,” the Production Manager has indicated.
In fact, it has been noted that, over the last several months, the performance of the second- and third-stage flash gas compressor on the Liza Destiny has been stable, and more than 96 percent of the gas produced has been reinjected and/or used to power the vessel.
“Recent optimisation tests have confirmed the performance of the previously upgraded equipment, and we were able to boost production to more than 140,000 barrels of oil per day, while maintaining the flare rates to a minimum,” he has said.
“Contrary to reports, with the previously installed machine, production on the Destiny would have had to be zero in order to achieve background flare. Since start-up in December 2019, we have managed production in a manner that balances the environmental commitment and economic needs of the country in alignment with Government priorities,” Ryan has posited.
Nevertheless, ExxonMobil Guyana has said it continues to work with the relevant Government agencies to ensure compliance with regulations and responsible development of the country’s natural resources.
Already, Guyana’s Environmental Protection Agency (EPA) was forced to amend the Environmental Permit for the Liza 1 Development Project last year, due to the increased flaring activities.
The regulatory body engaged Exxon’s local affiliate, Esso Exploration and Production Guyana Limited (EEPGL), to modify the permit back in May 2021 to include specific regulatory requirements for flaring of associated gas offshore Guyana, in accordance with the EPA’s legislation. These were missing from the original permit that was issued under the previous APNU/AFC Administration.
So far, the oil major has paid some US$8.3 million ($1.7 billion) for 17 billion cubic feet of gas flared since production started nearly three years ago.
EPA Executive Director Kemraj Parsram said last month that these figures included the 1.5 billion cubic feet of gas that was flared since the start of this year.
Meanwhile, the EPA has also renewed the Liza Phase 1 Environmental Permit and almost doubled the flaring fees for that development project. Similar flaring fines and strict water disposal stipulations have been included in the permits for the Payara and Yellowtail Development Projects. (G8)