Inefficient flaring, leaks from Exxon’s gas compressor could emerge as key problems

Dr Robert Kleinberg
Dr Robert Kleinberg

ExxonMobil should prove it is using efficient gas flaring technology in oil operations offshore and it is also imperative that both Guyana and the company have stringent measures in place to monitor for leaks from its equipment as such emissions have stronger greenhouse effects, physicist and energy researcher Dr Robert Kleinberg says.

“I would recommend that the equipment, as it ages, be monitored for leaks, which have a much stronger greenhouse gas effect than flaring,” Dr. Kleinberg told the Sunday Stabroek in an exclusive interview,  as he pointed to a study of 45 gas compressor stations in the United States’ natural gas transmission and storage system.

In that study, published in 2015 by the American Chemical Society (ACS), of the 45 stations studied, two were found to be “super-emitters” of methane, the main component of natural gas, with leak rates much higher than expected. (https://pubs.acs.org/doi/pdf/10.1021/es5060258)

Professor Kleinberg, who has worked for over 40 years in the oil and gas industry and whose work centres on energy technology and economics, and on environmental issues connected with oil and gas development, said that whenever there is flaring it needs to be monitored and ExxonMobil should be asked to certify they are using the best available technology during the process.

“Flaring is of course a negative factor, as it emits carbon dioxide into the atmosphere for no beneficial purpose.  Moreover, inefficient flaring is worse than efficient flaring…However, an inefficient flare allows some of the natural gas to escape unburned into the atmosphere.  Unburned natural gas has a much stronger effect on climate change than carbon dioxide,” he said, while referencing explanations he had presented to the American Geophysical Union last December.

“Therefore ExxonMobil should be asked to certify that they are using the best available technology to ensure flares are as efficient as possible,” he added.

The Sunday Stabroek reached out to ExxonMobil on plans for detecting and repairing compressor leaks and other equipment breakdowns and its maintenance regime but up to press time there had not been any response.

Offshore at its Liza-1 project, ExxonMobil has had to pause reinjection of associated gases and resort to flaring because of compressor glitches offshore and this has seen, over a six-month period, the flaring of more than nine billion cubic feet of natural gas.

On the 11th of June, the Sunday Stabroek had reported that as a result of persistent compressor problems, production at the Liza-1 had plummeted from 80,000 barrels per day (bpd) to between 25,000 and 30,000 bpd as the company restricted flaring to no more than 15 million cubic feet of natural gas per day.

The decision followed reports by this newspaper in early May that glitches during production startup saw flaring of over two billion cubic feet of natural gas—a figure subsequently confirmed by Head of the Environmental Protection Agency Dr Vincent Adams to be over nine billion cubic feet—even as the company had assured that it would have from that week begin transitioning to using the gas for well injection purposes.

On June 16, Exxon said that having fixed issues with two of its three gas handling systems thereby using 85% of associated gas from the reservoir, it had further reduced flaring at its offshore Liza-1 well project and had started to again ramp up production. 

“We continue to safely complete final commissioning of the gas handling system. We have two of the three gas handling systems online and are currently injecting or using 85% of the produced gas from the reservoir,” Public and Government Affairs Advisor Janelle Persaud said.

‘Challenging’

Dr Kleinberg, who was also a post-doctoral fellow at the ExxonMobil Corporate Research Laboratory and who worked with oilfields service provider Schlumberger, attaining the rank of Schlumberger Fellow and whose work focused on geophysical measurements and the characterization and delineation of unconventional fossil fuel resources, believes that Guyana’s offshore deep terrain can make compression difficult.

“From a technical standpoint, this [compression glitches] is not very surprising.  The Liza field is very deep, which makes gas compression challenging,” he said.

But he believes that “there is no question ExxonMobil is capable of deploying adequate gas compression systems to solve the present problem.”

ExxonMobil’s large volume of flaring is being monitored by the World Wildlife Fund (WWF) as the organization said that the company must play its part in decreasing emissions. Global environmental and human rights organization;  the Center for International Environmental Law (CIEL) and researchers and environmental watchdogs have all said that the flaring will significantly impact this country’s 2020 greenhouse gas (GHG) emissions.

 “WWF is monitoring the situation closely. As scientists predict that we no longer have years but months to address our carbon emissions globally, the fossil fuel industry must play an increasing role in curtailing – not increasing their carbon emissions,” WWF Director for the Guianas David Singh had told the Sunday Stabroek.

“For countries like Guyana that are striving to establish green, low-carbon economies, the fossil fuel industry must step up and contribute meaningfully to a green agenda. Free-riding by, or subsidising carbon production companies must be curtailed,” he added.

Based on the carbon price under Guyana’s forest protection pact with Norway, the nine billion cubic feet of natural gas equivalent would be equivalent to the loss of 4,642 hectares of forest, which would be valued at US$24 million.

Under that agreement, which was signed in 2010, Guyana pledged to accelerate its efforts to limit forest-based GHG emissions and protect its rainforest as an asset for the world. As such, Norway provided financial support at a level based on this country’s success in limiting emissions with a price set at US$5 per tonne of CO2 equivalent.

Utilising the calculation, nine billion standard cubic feet of methane gas flared would amount to 4.8 million tonnes CO2 equivalent. Multiplying that by the US$5 carbon price reflected in the Guyana-Norway agreement indicates that this country theoretically would have lost US$24 million under that pact had it been from deforestation.

To further illustrate, according to Guyana’s 2018 Measurement, Reporting and Verification (MRV) report under the forest protection pact, this country lost 9,227 hectares of forest that year. The CO2 equivalent emissions from ExxonMobil’s nine billion cubic feet of gas flaring would be equivalent to 4,642 hectares of deforestation or more than half of this country’s annual total.

In a project estimated to last for at least 40 years, according to ExxonMobil, the company is still to develop some 14 other wells in the 0.6 million acres (26,800 square kilometers) Stabroek Block area, which holds a combined total of over approximately  8B barrels of oil equivalent.

‘Minimum’

It is why the Principal of Presidio Energy Technology and adjunct senior research scholar at the Center on Global Energy Policy of Columbia University, who has authored more than 120 academic and professional papers and holds 41 U.S. patents, says that the company must show its plan for detecting compressor problems and leaks.

“ExxonMobil should have a plan for detecting and repairing compressor leaks and other equipment breakdowns that will arise in the future, without having to resume excessive levels of flaring,” Dr. Kleinberg said.

He reminded that ExxonMobil is a member of the Methane Guiding Principles (MGP) organization.

In an effort to reduce methane emissions globally, the MGP was formed and in 2017 a set of Methane Guiding Principles were developed collaboratively by a coalition of industry, international institutions, non-governmental organisations and academics to guide their work.  The organsisation’s website states that it is “a voluntary, international multi-stakeholder partnership between industry and non-industry organisations with a focus on priority areas for action across the natural gas supply chain, from production to the final consumer.”

It is to this end that Dr. Kleinberg posited that the company should be asked to keep its promises as pledged.

“At a minimum, the government and people of Guyana should ask ExxonMobil to live up to its own environmental standards. ExxonMobil is a member of the Methane Guiding Principles organization,” said Dr. Kleinberg, who for the last ten years has worked on environmental issues connected with oil and gas development including, among other things, methane emissions and flaring.

“This is an important story both for the people of Guyana and for global environmental welfare,” he said.

ExxonMobil’s 2020 Energy Carbon Summary also shows that the company had set a global performance standard in 2018, where it committed to 25% reduction in flaring from the 2016 benchmark by 2020. This is equal to a commitment of a maximum flaring of 397.5 million standard cubic feet (MMscf)/day in 2020.

“ExxonMobil is committed to mitigating emissions in our operations. As we grow our business to meet increasing demand, we are working to minimise the resulting increase in emissions. In 2018, we announced our GHG emissions reduction measures that are expected to lead to considerable improvements in emissions performance when compared with 2016 levels. These include: 15 percent reduction in methane emissions by 2020, 25 percent reduction in flaring by 2020, 10 percent GHG emissions intensity reduction at imperial operated oil sands by 2023,” the report states.

In Guyana, the emissions at Exxon’s Liza-1 project alone of 80 MMscf/day would represent 20.1% of the promised global threshold performance limit of the company.

And  even at 12 million cubic feet flaring per day, as it is now doing,  the carbon emissions are still significant and would be equivalent to 6,400 tonnes of CO2 being released per day or deforestation of 6.2 hectares (15.3 acres).

Given Exxon’s global mitigation promises, it is unclear if their reduction in production had less to do with the company being concerned about maintaining good relations with the EPA or meeting Guyana’s green agenda, than it had to do with its own sustainability commitments.