Carbon is the fourth most abundant substance in the universe. It takes many forms, from diamond and coal, to liquid hydrocarbons, carbonate rocks and even CO2 gas. But although these are all useful, carbon in the atmosphere is harmful in large amounts-so the race is on to store it safely or convert it to other states that are not harmful to the environment.
There has accordingly been a concerted effort from governments, regulators, utilities, and energy businesses to develop affordable, safe and practical carbon capture and storage (CCS) solutions to meet global net zero targets.
Three distinct challenges are holding back CCS adoption in the oil and energy sector; principles which share a common solution in the introduction of effective, real-time monitoring infrastructure and analysis.
Relatively mature CCS processes employed by oil and energy companies involve injecting CO2 into underground storage reservoirs, typically decommissioned oil and gas wells. But as with any subsurface installation, ensuring safety and integrity across its multi-decade lifespan is key to accruing support from investors, business partners and the wider public.
Failure to securely retain CO2 significantly damages the credibility of CCS at large. In one recent high-profile example in Australia, the struggles of a CCS site have been covered extensively by global media for its inability to manage risks, for which the project partners could face millions of dollars in fines.
Investors and the wider public need proof that CCS is a durable solution capable of permanently removing CO2 from general circulation-without effective, realtime data capture and analysis, this proof is lacking.
Although the potential market is significant and interest from international governments and legislators is on the rise, CCS currently requires oil and energy businesses to commit to expenditure that doesn't necessarily generate revenue at present. CCS sites require permanent monitoring infrastructure for well integrity, injection optimization, and much more, demanding expensive processes which carve out increasing shares of the potential revenue stream.
Seismic surveying, for instance, is key to establishing the suitability of prospective CCS sites; assessing such conditions as composition and properties of the reservoir rock, including its permeability, and the integrity of the well site. Traditional approaches to imaging the subsurface are very expensive, costing in the range of tens of millions of dollars-a prohibitive factor for CCS as an emerging market. Equally, beyond site establishment and start-up, routine monitoring of reservoir integrity would require a rolling campaign of expensive and potentially risky seismic surveys across its lifespan.
The CCS industry stands to benefit greatly from improving its understanding of the readily available, cost-effective monitoring alternatives that its data partners and existing infrastructure can provide for CCS installations.
The technical readiness of CCS is hampered by a shortage of firms in the market that can guide businesses throughout the entire CCS monitoring process. As traditional oil and gas firms streamline their R&D departments in a bid to stabilize balance sheets, they do not necessarily possess as much in-house expertise as they did in previous years-and certainly not in the relatively new realm of CCS.
Meanwhile, as governments increasingly drive momentum of CCS with new legislation, tax benefits, carbon credits and other initiatives, the industry needs to be ready to accommodate the resulting spike in demand. The amount of CO2 storage available today will need to increase by around 100 times if it is to help us meet the International Energy Agency's (IEA) 2050 net-zero requirements.
The ability to provide instantaneous insights into volumes of CO2 captured, transported and stored, and identify any issues or down well events, will be critical to realizing commercial advantages as the sector gains traction. This is not achievable with legacy techniques common to the industry. Improved data monitoring activated by real-time data capture is the way forward for a successful CCS sector.
Distributed fiber optic sensing (DFOS) technology, which uses fiber optic cables to trace the movement of substances such as oil, sand, water and gas through the subsurface, as well as monitoring well and pipeline integrity, can act as a major enabler to the industry. Recent advances in data analysis methodology have significantly reduced processing times for the large volumes of data generated through fiber optic cables, unlocking new uses throughout the energy sector and beyond.
With DFOS applications such as distributed acoustic sensing (DAS) and distributed temperature sensing (DTS), oil and energy operators can use advanced data analysis to monitor CO2 during transport, injection, and storage in the reservoir, and for continuous monitoring for leaks throughout the project lifecycle. This arms them with the means to demonstrate the effectiveness of their sites, and solidify the credibility of the CCS sector.
DFOS is just the beginning. Other cost-effective sensors could be integrated into this analysis model in future for a multi-faceted approach to data capture. This sensor fusion model could have tangible benefits to offer the CCS industry in terms of data accuracy, transparency, and more.
Three steps for a viable long-term CCS solution
1. Set up the site for effective monitoring
Seismic surveys are a necessary investment in the establishment of CCS sites, so it's important to accrue as much value out of them as possible. Utilizing these surveys to map out the best opportunity for DFOS monitoring across the site either in determining the placement of fiber optic cables and sensors in existing infrastructure, or in charting installation of new cables and sensors-gives operators the opportunity to secure the greatest oversight of the project.
Real-time monitoring facilitated by DFOS enables project managers to compare dynamic site behaviors during start-up against the expectations outlined by the initial survey. The ability to correlate and form conclusions from two datasets reinforces the credibility of site expectations for stakeholders, and improves their trust both in the individual project and the CCS industry as it scales.
2. Monitor the journey of CO2, from transport to injection
To deliver maximum benefit for CCS operators, monitoring needs to provide instantaneous insight into CO2 movements. This process is dynamic, so understanding the flow of gas in real-time is vital-especially during the injection phase. Using real-time DFOS offers operators a more dynamic picture of down well events as they occur, helping to spot any leaks early.
The same applies when transporting CO2 from the production site to the storage site-whether this is through pipelines or shipping. Any discrepancies in the final amount of CO2 undergoing injection can be accounted for and used to improve transport processes. DFOS-enabled monitoring also empowers operators to capture future commercial imperatives by accurately quantifying and auditing the volume of CO2 transported and stored.
3. Trim down-time with permanent solutions
Inescapably, traditional monitoring methods are invasive and irregular in the results they produce. Wireline logging, for instance, only provides static snapshots of data at particular times, which is unsuitable for monitoring the dynamic nature of downhole events, and also requires repeated well interference for each survey -potentially damaging well integrity and leading to leaks. Equally, for every seismic survey or wireline log, hundreds of personnel must be transported to the site, which may be remote or in a hazardous environment.
This, again, is where real-time DFOS is superior to alternative methods. With real-time DFOS combined with advanced data analytics, operators can monitor emerging trends within the site continuously as it operates, catching any leaks before they become a problem. Fiber optic cables will also not degrade for decades, further limiting the need for additional interventions-removing health and safety risks which threaten the safe reputation of the sector, and preserving its commercial credibility through continuous operation.
The future of CCS
The success of CCS will shape the future of the energy sector, so we must make it a success. This endeavor requires widespread collaboration for the oil and energy sector to address the missing pieces in its bedrock of expertise. Proactively identifying and engaging with data analysis experts, with the experience to guide data acquisition and monitoring processes for CCS, will arm the industry with critical insights to build trust, control costs, and reinforce this expansion.
The oil and energy sector is coming to terms with the digital transformation required to meet the needs of the future energy landscape-for CCS this is no different. Without the latest in data monitoring and analysis methods, the CCS industry faces a steep uphill climb to credibility and commercialization. Its success will depend on how quickly its incumbents are prepared to adapt to a digitized future.