A carbon capture and storage (CCS) facility in Alberta, Canada has produced more carbon than it has captured over the last five years, according to a study by Global Witness.

As the energy transition accelerates, focus has intensified on the development of fossil fuel alternatives such as green hydrogen and carbon capture. 

Shell’s Quest CCS project has been described by the company as being a ‘thriving example’ of how CCS technology can significantly reduce carbon emissions. 

However, a study released by non-governmental organisation (NGO) Global Witness (GW) has revealed that over the past five years Quest has captured 5m tonnes of carbon but during the same time period emitted a further 7.5m tonnes of ‘climate polluting gases’, a carbon footprint equivalent to 1.2m petrol cars. 

The use of Quest’s carbon capture technology is part of Shell’s efforts to produce fossil hydrogen, alternatively called blue hydrogen. 

GW’s report, entitled ‘Hydrogen’s Hidden Emissions’, also revealed that the process the plant uses to create hydrogen, known as steam methane reforming (SMR), only accounts for around 60% of the carbon emissions produced. 

The remaining 40% comes from the plant’s flue gas and are not captured by Shell’s CCS system. 

Only 80% of 60% of the carbon emissions produced at the facility are captured, giving a 48% capture rate. 

Having fallen short of industry’s promise that the plant will deliver a 90% carbon capture rate for fossil hydrogen projects, the plant’s 48% capture rate plummets to 39% when taking into account other greenhouse gas (GHG) emissions from Shell’s project.

Although 52% of carbon emissions are not captured, the study explained that the cost could be even higher, with its ‘off-site’ GHG emissions consisting of methane from the fossil gas supply chain and carbon emissions from the energy used to power the CCS system. 

By underdelivering on its promise to capture a much higher rate of CO2 capture, Shell could see its project joining the less-than-promising statistics that illustrate carbon capture’s track record. 

A study of 263 government-supported CCS projects showed that of the 127 large-scale projects in this dataset, 78% had been cancelled or suspended for three years or more. 

According to GW, the high project failure rate means that globally, existing CCS systems have the capacity to capture only 17% of the carbon emissions that announced CCS systems aimed to capture. 

The study proposes that energy companies must pursue carbon-free alternatives to fossil hydrogen such as green hydrogen and phasing out refineries if they are to meet the Paris Agreement goals by 2040.