Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - STEMM-CCS (Strategies for Environmental Monitoring of Marine Carbon Capture and Storage)

Teaser

Carbon dioxide Capture and Storage (CCS) has been identified as an important mitigation strategy to reduce anthropogenic carbon dioxide (CO2) emissions and combat the rising levels of atmospheric CO2 responsible for global climate change and ocean acidification. CCS is seen as...

Summary

Carbon dioxide Capture and Storage (CCS) has been identified as an important mitigation strategy to reduce anthropogenic carbon dioxide (CO2) emissions and combat the rising levels of atmospheric CO2 responsible for global climate change and ocean acidification. CCS is seen as a key contribution to reducing anthropogenic greenhouse gas emissions by 80-95% by 2050 and keeping climate change derived temperature increases below 2°C. Offshore storage of CO2 in depleted oil/gas reservoirs and saline aquifers is the preferred option for most European nations.

STEMM-CCS is an ambitious research and innovation project on geological CO2 storage that will deliver new insights, best practice guidelines and tools for CO2 storage at offshore CCS sites. The ability to predict, detect, monitor, and quantify CO2 leaks from sub-seafloor CCS reservoirs is crucial for driving deployment. The objectives of STEMM-CCS are to provide comprehensive guides, technologies and techniques to facilitate:
• Offshore CO2 storage site selection
• Undertaking risk assessments
• Monitoring CCS operations
• Quantification of fluxes from a leak
To achieve these aims, a controlled release of CO2 under the surface sediments will be carried out at the Goldeneye reservoir (North Sea). This experiment will test CO2 leak detection and quantification using advanced sensors to simultaneously measure parameters in the water column and surface sediments. Prior to the experiment, environmental and ecological baseline studies will be performed. A comprehensive geophysical field program will be conducted at a site similar to Goldeneye. Analysis of the geophysical data will be used to predict the permeability and distribution of fluid pathways (that determine the locations and rate of any potential CO2 release) in the sediment overburden.

Work performed

The STEMM-CCS project has achieved its goals for the first 36 months. We have produced the most extensive characterization of the seabed in the Central North Sea, compiling geological, hydrographical and chemical data for the area, which will be augmented by new data in the next year. This has enabled us to identify further data that are needed to fully understand the complex North Sea environment and to guide the design of our sampling procedure on the main research cruise. Advanced computer models have allowed us to identify the temporal behaviour of key biogeochemical features of the North Sea. We have also deployed a seabed lander equipped with a set of commercially available sensors and our newly developed suite of in situ instruments.

We have advanced a suite of in situ sensors to enable deployment on the release experiment cruise in spring 2019, including the most accurate and sensitive total alkalinity sensor ever produced. We have advanced and published techniques for automated analysis of images for baseline surveys. We have published a number of papers on the advancement of the models as part of the STEMM-CCS project.

Two geophysics cruises have taken place, gathering seismic data over an existing chimney structure in the North Sea and the deployment area for the experimental work in 2019. A third cruise performed the first drilling of a North Sea chimney structure, acquiring long sediment core samples from the Scanner pockmark in the North Sea. A series of baseline cruises have gathered data on the biogeochemistry of the sediments and water column in the Goldeneye area.

Novel engineering approaches have been used for the main release experiment equipment taking place in 2019. We have worked with a Canadian company, Cellula Robotics, to design a bespoke drill rig to insert pipes below the seabed to release the CO2 at the right depth and location for the study. We have designed and built a system to place 3 tonnes of CO2 onto the seabed safely. This will be linked to the release pipes and under the control of the ship above, CO2 will be released into the sediments. We have upgraded a commercial AUV to increase its capability, allowing more measurements of the chemical and physical environment during its photo imaging surveys of the seabed.

The project has generated interest from scientific, policy and public communities. It has featured in a number of key meetings, in the press as well as on a BBC science program. International interest in the project is increasing; our efforts to highlight the project more globally were rewarded by a high level of interest at the prestigious GHGT-14 meeting in Melbourne Australia, where we exhibited and gave a number of presentations. STEMM-CCS partners are on the advisory boards of projects in the USA and have growing links with Norwegian, Japanese and Australian funded projects.

Final results

STEMM-CCS will make advances in key areas that currently limit the operation of safe and environmentally sound CO2 storage in offshore geological reservoirs. The solutions for detection, quantification and monitoring are innovative and will include products with significant commercial potential. The following will be advanced beyond current state of the art:
• Resolution of natural and anthropogenic induced CO2 permeability of reservoir overburden.
• Observational techniques and models enabling efficient baseline acquisition.
• Cost effective tools for detection and quantification of CO2 leakage.
• Habitat and ecological mapping tools for large-scale high-resolution photography and acoustic mapping.
• Models for various reservoir leak morphologies and decision support tools for mitigation and remediation.
• Assessment of anthropogenic CO2 leaks against natural CO2 fluxes across sediment-water interfaces.
The controlled release of CO2 into sub-seabed sediments at the Goldeneye site will allow the first thorough testing of techniques used for the detection and quantification of CO2 fluxes to the marine environment.

Techniques and technologies to assess and monitor existing and planned offshore CCS sites do not exist. STEMM-CCS will deliver approaches that will allow risk and baseline assessment of sites and monitoring of operations. Where appropriate approaches will be commercialized, including:
• A first Relaxed Eddy Accumulation system for DIC/pCO2 flux from the Benthic Boundary Layer
• Integration of new high precision pH and O2 optodes in benthic landers and AUVs
• A first system for CO2 leak quantification via water current model inversion and carbonate system measurements
• Novel acoustic technologies for autonomous quantification of gas fluxes
• Optimised technologies for automated benthic image annotation for CCS mapping applications
• Decision support tools for site selection, monitoring system design, site operation and mitigation/remediation actions.
The technologies and tools that STEMM-CCS delivers will facilitate large scale deployment of CCS and increase the confidence of CCS operators and regulators to conduct cost effective surveys allowing compliance with legislation. This work will promote CCS as a CO2 mitigation strategy and build on the existing lead that Europe has in developing offshore CCS. It will drive collaboration with other nations, enhance cooperation between stakeholders and Member States and promote knowledge sharing thereby increasing confidence in, and public acceptance of CCS.

Website & more info

More info: http://www.stemm-ccs.eu.