CO₂ geological storage

The R&D team at TotalEnergies has been working for over twenty years on the development of CCS (Carbon Capture and Storage) to reduce its CO₂ emissions and those of its clients. The objective for 2030? To be able to store over 10 Mt CO₂ per year. The CCS chain involves three steps: capturing the CO₂ emitted by the industry, transporting it by vessel or pipeline, and storage in saline aquifers or former (oil or gas) reservoirs. A new industrial chain is emerging

An emerging solution

"In the Béarn region, a lot of people remember TotalEnergies’ CO₂ capture-transport-storage pilot in the Lacq basin in 2007. It was a first in Europe! In 2010, the Rousse reservoir and the capture facility were operational. For three years, up to 2013, more than 51,000 tons of CO₂ were successfully injected underground, in this small-scale pilot which demonstrated the capacity to implement a capture, transport and storage chain, now used in the industrial projects in the North Sea".

Luc Pauget,
CO₂ storage lead in the R&D department – Centre Scientifique et Technique Jean Feger – CSTJF Pau

In the Net Zero Emissions scenario issued by the International Energy Agency, the world will still be consuming oil and gas by 2050. In the light of this, solutions need to be found to capture, transport and store the CO₂ emitted by certain essential activities - power production, cement manufacturers, the steel industry - for which no other alternative will have been found. In 2023, the IPCC (Intergovernmental Panel on Climate Change) and the IEA (International Energy Agency) acknowledged CCS as one of the solutions to be developed to reduce greenhouse gas emissions.

On the quest for injection sites

"Now it’s all about industrializing the process: capturing the significant volumes of CO₂ emitted by industries, compressing the gas so that it can be transported as a liquid in pipelines or vessels at a temperature of -26°C, then mass-injecting it into subsurface reservoirs". Which means having suitable sites to do so, such as "depleted" oil and gas reservoirs which are no longer used, or saline aquifers. "We’re also working on the acceptability of these future storage areas for society”, Luc Pauget continues, "with transparent information on site assessment, risk management and surveillance". It also involves giving educational information about CO₂, a gas with a high global warming potential when it is discharged into the atmosphere, but which is part of our everyday lives. CO₂ puts the bubbles into champagne and mineral water, and boosts plant growth in glasshouses, etc. “We also need to show that almost-pure CO₂ can be contained in the subsurface long term. Amongst other aspects, the R&D department is working on the in-depth understanding of geological layers and trapping mechanisms, on the migration of CO₂ in the water in aquifers, and on simulations over hundreds and thousands of years".

Multiple operational projects

In the field, CCS is definitely taking hold. In August 2022, TotalEnergies and its partners signed the first business agreement in the world with Yara - ammonia and fertilizer manufacturers - for CO₂ sequestration and transport. As from 2025, 800,000 tons of CO₂ will be captured every year in the Netherlands and carried to the Northern Lights site in Norway, to be injected subsurface. In the initial phase, the site injection capacity will reach 1.5 Mt/yr, and 5-6 Mt/yr in phase 2. Alongside that, TotalEnergies, Shell, Énergie Beheers Nederland and Gasunie are developing Aramis, another project in the Netherlands, aiming to achieve a CO₂ storage potential of 8 Mt/yr as of 2030, i.e. the equivalent of half the annual emissions from air transport in France, which is a pretty good start! The Bifrost project in Denmark will contribute to the creation of efficient infrastructures to transport the CO₂ from European industrial hubs to offshore storage points in the North Sea. In 2023, TotalEnergies obtained permits for the Harald gas field and a salt aquifer (5Mt of CO₂ per year as from 2030). The sector is taking shape.

"The R&D teams at TotalEnergies are looking beyond the storage chain, which helps reduce industrial emissions. For example, they are investigating the Direct Air Capture (DACS) of CO₂ which will one day reduce emissions, and also “repair” the atmosphere (known as negative emissions). They are also making progress on storage in the form of carbonate rocks, its use in manufacturing green fuel, or in a revolutionary geothermal loop. Watch this space!", explains Luc Pauget, CO₂ storage lead in the R&D department – Centre Scientifique et Technique Jean Feger – CSTJF Pau.

Coralie Girard, Engineer and Head of the Gas Separation and Treatment Laboratory at the Platform for Experimental Research in Lacq (PERL), adds: "There are still some barriers to overcome. At the PERL, we are looking into more efficient, more compact processes, and (liquid and solid) materials that can capture greater quantities of CO₂ and reduce investment and operational costs. Alongside that, we are also making progress on reducing the impact of capture facilities on the environment. Two technologies are being investigated: the first is based on the use of liquids to trap CO₂. The second consists in trapping CO₂ in a porous solid. One of the current obstacles to the use of these technologies is the energy required to operate them".