Carbon Capture Realities, Promising Future?

What is Carbon Capture?

Carbon capture is the process of trapping carbon dioxide (CO₂) emitted from industrial activities or the atmosphere and preventing it from entering the air. In practice, this usually means collecting CO₂ from large point sources – like power plant exhausts or factory flue gases – and then either utilizing it for some purpose or storing it so it doesn’t contribute to global warming. This full chain is often called carbon capture, utilization, and storage (CCUS). For example, the International Energy Agency defines CCUS as capturing CO₂ from fuel combustion or industrial processes, compressing and transporting it, and then either using it in products or injecting it into deep geological formations (such as depleted oil/gas fields or saline aquifers). In simple terms, carbon capture means taking CO₂ out of smoke stacks (or even out of the open air) and locking it away or turning it into something useful.

The primary goal of carbon capture is to reduce the amount of CO₂ that we release into the atmosphere, thereby helping to mitigate climate change. Many climate models and national net-zero plans include CCS/CCUS as a crucial tool to handle emissions from sectors that are hard to decarbonize (like cement or steel plants) or to achieve “negative emissions” in the future by removing CO₂ directly from air. However, as we will discuss, traditional carbon capture and storage has faced significant challenges in implementation, leading to interest in new approaches that don’t just store CO₂ but also convert it into valuable materials.

Source: Congressional Budget Office, U.S. Federal Government

Traditional Carbon Capture Methods

Several methods have been developed to capture CO₂ from industrial processes. The three classic approaches are post-combustion capture, pre-combustion capture, and oxy-fuel combustion. Each method involves a different stage of the fuel-burning process at which CO₂ is separated:

• Post-Combustion Capture: In this widely studied method, CO₂ is removed after burning the fuel. The CO₂ is “scrubbed” out of the flue gas (the mixture of gases leaving a power plant’s smokestack) using chemical solvents or filters. This approach can be retrofitted to existing power plants because it treats the exhaust gases without altering the combustion process. Post-combustion capture is already used in some industries – for instance, amine solvent scrubbers are common in natural gas processing to remove CO₂. It’s also the method used by notable projects like SaskPower’s Boundary Dam in Canada (a coal power plant retrofitted with CO₂ capture) and the Petra Nova project in the U.S. (attached to a Texas coal power plant). Petra Nova’s system, which began operation in 2016, was designed to capture about 1.4 million tons of CO₂ per year from the plant’s exhaust (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters). The captured gas in that case was compressed and sent via pipeline to an oil field for storage and oil recovery (more on that later). Post-combustion systems are advantageous because they can be bolted onto existing plants, but they do impose a significant energy penalty – meaning the power plant has to use some of its energy output to run the capture equipment, often 20-30% of the plant’s power.

• Pre-Combustion Capture: This method catches the carbon before the fuel is burned. It typically involves converting the fuel into a mixture of gases from which CO₂ can be extracted. For example, coal or natural gas can be reacted with oxygen or steam in a gasifier to produce syngas (a mixture of hydrogen, carbon monoxide, CO₂, etc.). Then the CO₂ can be separated from that syngas stream, yielding a clean hydrogen fuel that can be burned with low emissions (Understanding carbon capture and storage - British Geological Survey). The hydrogen is used for energy, while the CO₂ is captured for storage. Pre-combustion capture is inherently part of processes like coal gasification or making hydrogen from natural gas – it’s already used in some fertilizer plants and hydrogen production facilities where CO₂ is a byproduct. It tends to be more efficient than post-combustion and produces a concentrated stream of CO₂, but it usually can’t be retrofitted easily; it requires an integrated design (a power plant built as a gasification plant, for instance). A high-profile attempt to use pre-combustion CO₂ capture in a power plant was the Kemper County project in Mississippi, which planned to gasify coal and capture the CO₂, though that project ran far over-budget and eventually abandoned the CO₂ capture component. On the other hand, natural gas processing sites like Norway’s Sleipner field have for decades removed CO₂ (which occurs naturally in some gas) before sending the gas to customers, and in Sleipner’s case they have injected about a million tons of CO₂ per year into a saline aquifer under the North Sea since 1996 (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com) (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com) – an early successful example of carbon capture and storage.

• Oxy-Fuel Combustion: This approach tries to make CO₂ capture easier by changing the combustion process itself. Instead of burning fuel in normal air (which is 78% nitrogen, 21% oxygen), oxy-fuel combustion burns the fuel in pure oxygen or oxygen-enriched air. With nitrogen largely out of the picture, the exhaust gas is mostly CO₂ and water vapor. The water can be condensed out by cooling, leaving a nearly pure stream of CO₂ to be captured (Understanding carbon capture and storage - British Geological Survey). In essence, you eliminate the diluting effect of nitrogen in the flue gas. Oxy-fuel combustion can achieve very high CO₂ capture rates (sometimes touted as “zero emission” combustion) (Understanding carbon capture and storage - British Geological Survey). The drawback is that producing pure oxygen itself is energy-intensive (typically done by cryogenic air separation or other means), so the overall process can be costly. Oxy-fuel combustion has been demonstrated in pilot projects. One famous pilot is the Schwarze Pumpe facility in Germany, where a 30 MW coal boiler was run on pure oxygen; it captured about 50,000 tons of CO₂ over a few years of tests around 2008-2014. The CO₂ from that pilot was compressed and transported off-site (in tanker trucks) for storage. (Image: below shows a CO₂ tanker used at the Schwarze Pumpe oxy-fuel pilot in Germany) A tanker truck carrying liquefied CO₂ from Vattenfall’s Schwarze Pumpe oxy-fuel carbon capture pilot plant in Germany. The text on the tank (in German) notes it as a “CCS pilot project” for climate protection. Oxy-fuel technology proved that you can indeed produce a CO₂-rich exhaust for easier capture, but scaling it up has been slow due to the efficiency penalty of supplying oxygen. Some new designs for power plants (and even ship engines) continue to investigate oxy-fuel as a route to simplify CO₂ capture.

  

Source: Source:CO2 Transportfahrzeug Oxyfuel KW Schwarze Pumpe.jpg - Wikimedia Commons

These traditional carbon capture methods are all aimed at grabbing CO₂ from industrial processes. Once the CO₂ is captured by any of these methods, it needs to be compressed and transported to a site for either utilization or permanent storage. The compression typically turns CO₂ into a high-pressure fluid (supercritical CO₂) that can be pumped through pipelines. Transport can be via pipelines (the cheapest for large volumes), or sometimes by ship or truck for smaller scales. In regions like the United States, there is already an extensive network of CO₂ pipelines – for instance, about 5,800 km of pipelines in the U.S. transport CO₂, mainly to oil fields. This leads us to one of the primary “utilization” pathways historically: injecting CO₂ into oil wells.

Enhanced Oil Recovery: Using CO₂ to Pump More Oil

One of the longest-running industrial uses of captured CO₂ is Enhanced Oil Recovery (EOR). In EOR, CO₂ is injected into declining oil reservoirs to force more oil out of the ground. The CO₂ helps pressurize the reservoir and can dissolve into the oil, making it less viscous so it flows to production wells more easily. Oil companies have used CO₂ for decades to boost output from older fields, especially in places like West Texas (Permian Basin) and the North Sea.

In fact, most CO₂ being captured or transported today is tied to EOR operations. Globally, a majority of the current carbon capture projects send CO₂ to oil fields. A recent analysis noted that of the 42 operating CCS projects worldwide as of 2023 (collectively capturing ~49 million tons CO₂ per year), 78% of the captured CO₂ is used for EOR (Explainer: Why carbon capture is no easy solution to climate change | Reuters) (Explainer: Why carbon capture is no easy solution to climate change | Reuters). The rest is injected purely for storage without producing oil. The CO₂ for EOR historically often came from naturally occurring underground CO₂ reservoirs (for example, CO₂ wells in Colorado or natural CO₂ domes in the US), but increasingly, anthropogenic CO₂ from capture projects is being used.

How EOR works: Companies compress and inject CO₂ into an oil formation, push more oil out, then produce a mixture of oil and CO₂. The CO₂ that comes back up is separated and usually re-injected in a loop, so a good portion of the CO₂ can end up permanently trapped underground in the process. However, eventually some CO₂ does remain stored in the reservoir pores. EOR effectively stores CO₂ while also yielding additional oil – which is both a pro and a con environmentally.

Examples of CO₂-EOR in action: A noteworthy project was Petra Nova in Texas, mentioned earlier. It captured CO₂ from a coal power plant and piped it about 80 miles (130 km) to the West Ranch oil field (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters). By injecting that CO₂, the oil field’s output increased (the project was intended to yield millions of extra barrels of oil). Another example is in Canada: the Weyburn-Midale project, which since 2000 has been taking CO₂ (captured at a coal gasification plant in North Dakota) and injecting it into the Weyburn oil field in Saskatchewan. Over 30 million tons of CO₂ have been stored through that EOR project while boosting oil production. In the North Sea, Norwegian company Equinor (formerly Statoil) has done CO₂ injection not for oil but for pure storage (Sleipner field), but they also planned EOR pilots. In the Middle East, Abu Dhabi’s state oil company ADNOC started a CO₂-EOR project in 2016 (Al Reyadah project), capturing CO₂ from a steel plant to inject into oil reservoirs.

Limitations of EOR: While EOR provides a revenue stream for captured CO₂ (the oil pays for the CO₂ injection operation), it has obvious limitations as a climate solution. The very goal of EOR is to produce more oil, which will eventually be burned, putting CO₂ back into the atmosphere. Analyses differ on the net carbon balance of CO₂-EOR – some of the injected CO₂ stays underground, but if the extra oil leads to additional CO₂ emissions, the overall benefit can be small or even negative for the climate. Moreover, the demand for CO₂ for EOR is ultimately bounded by how many suitable oil fields are available and economic. It’s not a limitless sink for CO₂. There are also physical constraints; not all reservoirs can retain all of the injected CO₂ once oil production stops – some CO₂ might eventually migrate if not properly managed, though studies show well-chosen geological sites can retain over 99% of injected CO₂ over millennia.

Source: https://carboncapturecoalition.org/wp-content/uploads/2018/01/Melzer_CO2EOR_CCUS_Feb2012.pdf

Economically, EOR has been a driver for early CCS projects, but it is sensitive to oil prices. Petra Nova’s experience illustrates this: when oil prices crashed in 2020, Petra Nova was shut down because the added oil recovery profits dried up and could no longer justify the cost of running the capture system (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters) (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters). (It remained offline for over three years and only restarted in late 2023 when market conditions improved, as its owners hoped to give the project a “second chance” (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters).) This volatility underscores that traditional CCS tied to oil can be financially shaky. EOR might make CCS profitable when oil is pricey, but it’s not a stable long-term climate solution if it hinges on continued oil production.

The Current State and Challenges of CCS

After decades of development, how much CO₂ are we actually capturing and storing today? The honest answer is: not nearly enough to meet climate targets. As mentioned, on the order of 40–50 million tonnes of CO₂ per year are currently being captured by all operational CCS projects worldwide – that’s only 0.13% of global CO₂ emissions (global energy-related CO₂ emissions are around 37 billion tonnes per year) (Explainer: Why carbon capture is no easy solution to climate change | Reuters). In other words, more than 99.8% of our annual CO₂ emissions are still going into the atmosphere. CCS has a gigantic scale-up mountain to climb to make a dent in climate change.

One issue has been that many CCS projects have failed to materialize or underperformed. A study of CCS efforts from the 2000s and 2010s found that historically about 88% of proposed CCS projects were not completed as planned (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change). Especially in the first wave of enthusiasm (around 2008–2012), many big CCS projects were announced – mostly attached to power plants – but the majority were canceled due to cost, technical difficulties, or lack of policy support. In that early wave, over 90% of the planned power-sector CCS projects fell through (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change). The current wave of CCS plans (including more in industrial sectors, not just power) might do better, but even optimistic forecasts suggest a failure rate around 50% or more of projects. If all current announced projects get built, we’d reach ~0.34 Gt (340 million tonnes) CO₂ capture capacity by 2030; but if typical failure rates continue, we might only see a fraction of that (perhaps ~0.07–0.1 Gt by 2030) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change). This is far below what climate models say is needed (on the order of several Gt per year of CCS by 2030 to align with a 2°C or 1.5°C pathway).

Why is CCS deployment so slow? Cost is a major barrier. Capturing CO₂ from flue gas isn’t cheap: conventional CCS on power plants can cost anywhere from $~15 up to $120 per ton of CO₂, depending on the technology and scale (Explainer: Why carbon capture is no easy solution to climate change | Reuters). (Capturing from dilute sources like the air is even more expensive, in the hundreds of dollars per ton range (Explainer: Why carbon capture is no easy solution to climate change | Reuters).) These costs make widespread adoption difficult without either a high price on carbon or substantial subsidies. For power plants, adding CCS often increases the cost of electricity significantly, which utilities and consumers may be reluctant to bear unless forced by regulation or incentivized by policy. A number of high-profile projects were halted for financial reasons – for example, the Scandinavian project at Norway’s Mongstad power plant was canceled in 2013 after being dubbed “Moonshot” for its expense, and Canada’s SaskPower had to reconsider future CCS because the Boundary Dam project proved more costly and captured less CO₂ than hoped. Even in the oil and gas industry, companies like Shell and Chevron had early setbacks (such as the Gorgon LNG project in Australia initially failing to meet its CCS targets due to technical problems).

Another challenge is infrastructure and geography. For CCS to work, you need a suitable place to put the CO₂. Not every region has a convenient deep geological storage site nearby. This means building long pipelines to transport CO₂ from where it’s captured to where it can be injected. We’re beginning to see plans for “CO₂ transport hubs” or clusters. Just today (April 24, 2025), the UK government and Italy’s Eni announced approval for a 38-mile CO₂ pipeline connecting industrial sites in the Liverpool-Manchester area to a storage reservoir under the sea. This project – part of the HyNet North West cluster – is essentially a “CCS corridor” to shuttle CO₂ from factories to an offshore storage site. The UK government is backing this with significant funding as part of a £21.7 billion support package for CCS development. Such pipelines and storage hubs (also being developed in the U.S. Gulf Coast, Norway’s North Sea, and elsewhere) are critical infrastructure, but they are large investments that typically require government support and public acceptance. Building a network of CO₂ pipelines raises safety and permitting considerations, especially when traversing populated areas.

Despite these challenges, governments and industries are still pushing CCS as a necessary tool – especially for industries like cement and steel where alternatives are few. However, the reality today is that traditional CCS alone is not on track to meet climate goals (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com) (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com). The slow rollout and frequent setbacks have even led some to label CCS a “failure” to date (at least in the power sector context). It’s clear that if CCS is to contribute meaningfully, either massive policy intervention (like high carbon prices or subsidies) must occur, or the technology must find a way to pay for itself. This is where a new wave of ideas comes in: using captured carbon not just for oil, but to create valuable products. The hope is that such approaches could make CO₂ capture economically attractive and overcome the “negative cash flow” problem of traditional CCS.

Beyond Storage: Turning CO₂ into Valuable Products

Instead of treating CO₂ solely as a waste to bury underground, what if we treat it as a raw material for making things? This concept is driving a lot of research into carbon capture and utilization (CCU). CCU covers a range of technologies aiming to convert CO₂ into useful products – fuels, chemicals, building materials, or even new forms of carbon. If successful, CCU approaches could create a revenue stream from CO₂, offsetting capture costs and encouraging more CO₂ removal in the first place.

Some current CCU examples include: using CO₂ to cure concrete (e.g. injecting CO₂ into concrete mixes to strengthen them and lock the CO₂ into calcium carbonates), converting CO₂ into synthetic fuels like methanol or aviation fuel (by reacting it with green hydrogen, for instance), making polymers (certain plastics components from CO₂), and even feeding CO₂ to algae to produce biofuels or proteins. However, many of these routes face their own challenges – often needing a lot of energy or hydrogen, or having relatively small market sizes.

One particularly innovative approach that has gained attention is turning CO₂ into solid carbon materials. If you could economically convert CO₂ into carbon in a solid form (like carbon black, graphite, or carbon nanotubes), you would both sequester the carbon (since solid carbon is stable and not a greenhouse gas) and obtain a material that might be sold for various applications. Notably, carbon nanotubes (CNTs) and related nanocarbon materials are very valuable by weight – they are used in electronics, nanotechnology, composites, batteries, etc. – which opens the possibility that CO₂ could become a feedstock for high-value manufacturing.

Molten Salt CO₂ Conversion (Carbon Nanotubes from CO₂)

One of the most promising methods for CO₂-to-carbon conversion is using molten salt electrolysis. Researchers have been developing electrochemical processes where CO₂ gas is bubbled through a cell containing a molten salt (often a carbonate or a mixture of carbonates), and with the application of electricity, the CO₂ is split into solid carbon (which deposits at one electrode) and oxygen (released at the other electrode). Essentially, it’s like running a CO₂ “splitting” reactor powered by electricity – analogous to how water can be split into hydrogen and oxygen via electrolysis, here CO₂ is split into carbon and oxygen via a high-temperature electrolysis.

(Overview of CO2 capture and electrolysis technology in molten salts: Operational parameters and their effects) Schematic of a molten salt electrolysis system converting CO₂ to solid carbon (deposited on the cathode) and oxygen (released at the anode). CO₂ is absorbed into the molten carbonate electrolyte and then electrochemically reduced to carbon.

In molten carbonate (typically a mix of lithium, sodium, potassium carbonates), CO₂ will react to form carbonate ions (CO₃²⁻) in the melt. At the cathode (negative electrode), those carbonate ions get reduced (with input of electrons) to produce solid carbon and oxide ions; at the anode (positive electrode), oxide ions release electrons and form O₂ gas. The net reaction is: CO2→C (solid)+O2↑,, driven by electricity and the chemistry of the molten salt. This process both captures CO₂ (the melt absorbs CO₂) and converts it, so it can be seen as a combined capture-conversion technique.

According to a 2023 review paper on molten salt CO₂ electrolysis, this approach has demonstrated very encouraging efficiencies in the lab. Many experiments report CO₂-to-carbon conversion efficiencies above 80% and current efficiencies over 90%, meaning most of the input CO₂ is indeed being converted to solid carbon with minimal losses, and the electrical input is being effectively used for the reaction. The resulting carbon can take forms like carbon nanotubes, carbon nanofibers, graphene flakes, or amorphous carbon, depending on the exact conditions (materials of electrodes, additives, temperature, voltage, etc.). For instance, using certain metal catalysts at the cathode can encourage the carbon to grow as nanotubes. By tweaking the molten salt composition (adding, say, lithium carbonate to lower melting point, or adding oxide additives), researchers can influence the morphology of the carbon product and optimize CO₂ absorption.

Why is this exciting? Because it addresses the fundamental economic issue of CCS. As the review paper noted, the current CCS projects face a “dilemma” of negative cash flow – they cost a lot and generate little to no revenue. But if the CO₂ could be turned into a valuable commodity, the whole equation changes. Molten salt CO₂ conversion has the potential to yield materials like CNTs that are worth thousands of dollars per ton (in some cases much more, depending on purity and properties). Even more bulk forms like graphite or carbon black have industrial markets (tires, batteries, electrodes, etc.). Instead of paying to dispose of CO₂, companies could sell the carbon produced. In the words of the researchers, molten salt CO₂ electrolysis could provide a “promisingly positive cash flow” while achieving CO₂ reductions.

Additionally, this process produces oxygen gas as a byproduct, which could potentially be captured and used (industrial O₂ has value as well). The solid carbon is much easier to store or handle than gaseous CO₂ – it’s stable and won’t leak back into the air. Essentially, carbon from CO₂ could be sequestered in useful solid forms for long periods (if not indefinitely).

Several tech startups and research groups are actively developing this concept towards commercial scale:

• CarbonCorp (USA): Originating from the research by Professor Stuart Licht (who pioneered the “C2CNT” process), CarbonCorp uses a molten salt electrolysis system – branded as the C2CNT® “Genesis Device” – to convert CO₂ into carbon nanotubes and graphene (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon) (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon). They emphasize that the only input is CO₂ (which can come from industrial flue gas or even directly from air) and that instead of emitting CO₂, one produces strong carbon materials. CarbonCorp touts applications of their carbon nanotubes in enhancing materials like concrete, aluminum, plastics, etc., claiming huge potential CO₂ savings by lightweighting or strengthening these materials (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon) (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon). This company was a finalist in the Carbon XPRIZE competition and is part of a growing push to create a “nanocarbon economy” from CO₂.

• SkyNano (USA): SkyNano is a startup that spun out of research at Vanderbilt University and Oak Ridge National Lab. They have a process to capture CO₂ from dilute industrial emissions and electrochemically convert it into carbon nanotubes and other advanced carbon powders (SkyNano | Transform CO2 into advanced carbon materials). SkyNano’s approach also uses molten salts and aims to be a modular, on-site solution. They recently opened a pilot production facility in Tennessee to scale up this technology. The company emphasizes that the solid carbon it produces offers permanent storage of CO₂ (since it is locked into a stable solid form) while also creating materials that improve batteries, tires, coatings, and more (SkyNano | Transform CO2 into advanced carbon materials) (SkyNano | Transform CO2 into advanced carbon materials). In essence, they pitch their tech as carbon capture, utilization, and storage all in one, since the carbon product is itself the storage medium.

• UP Catalyst (Estonia): In Europe, UP Catalyst is another company focusing on CO₂-to-carbon via molten salt. They have developed an electrolysis method to produce carbon nanotubes and graphite from CO₂ and are working on making the process more sustainable by recycling the molten salt electrolyte. A recent consortium project (MoReCCU) led by UP Catalyst is developing a molten salt regeneration system to allow the carbonate salts to be reused 100+ times, addressing a cost issue with continuously replenishing salts (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News). UP Catalyst’s process has been demonstrated using CO₂ from industrial exhaust, and they are positioning it as a way to make carbon nanomaterials with net-negative emissions (since you’re effectively storing CO₂ in the product) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News). They have shown applications like using the CO₂-derived carbon in battery electrodes (for sodium-ion batteries) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News).

These are just a few players – the field is growing as the need for profitable carbon removal grows. Even large companies and governments are taking note: for instance, the U.S. Department of Energy has funded research into CO₂-to-CNT (the ORNL collaboration with SkyNano, and others), and some oil companies have shown interest in carbon-to-value technologies as part of a “circular carbon economy” concept.

Why Carbon Conversion is Appealing

The new approaches that convert CO₂ to materials have several key appeals over traditional CCS:

• Economic Value: The most obvious advantage is turning waste into a product. Instead of solely incurring costs to capture and store CO₂ (with the hope of a carbon credit or avoiding a carbon tax), a company could sell the carbon it captures. This could fundamentally improve the business case of capture. For example, carbon nanotubes can sell for tens of thousands of dollars per ton for specialty grades. Even if produced at commodity scale, carbon materials could offset a significant fraction of capture costs. The reviewed research explicitly states the goal of making CO₂ capture profit-generating for end users. This carrot of profit could incentivize more companies to install carbon capture, because it’s no longer just an environmental compliance measure, it’s also potentially a revenue stream.

• No Need for Long-Term Storage Monitoring: If CO₂ is converted to a stable solid and used in products, we likely don’t need to worry about it leaking out of a geological storage site in the future. Geological storage is generally considered safe with proper site selection, but it still requires monitoring and has a small risk of leakage or induced seismicity. Storing carbon in the form of, say, carbon fiber in a car or CNTs in concrete means the CO₂ is essentially stored as a solid part of our infrastructure or goods. It’s a more tangible form of storage – potentially even permanent if the carbon eventually ends up landfilled or recycled into new products.

• Reduced Environmental Risk: Traditional CCS involves handling large volumes of CO₂ gas under high pressure, transporting them, and injecting underground. There have been concerns about pipeline ruptures or CO₂ blowouts (CO₂ is not toxic per se, but in high concentration it can asphyxiate and it’s heavy, so leaks can be a hazard). Using CO₂ on-site to make solids would localize the carbon, reducing the need for long-distance transport of CO₂ and the associated risks.

• Synergy with Renewable Energy: The molten salt electrolysis needs a significant amount of electricity (and heat) to run. As solar and wind power become cheaper, especially in regions with abundant resources, there is a great opportunity to use excess renewable energy for CO₂ conversion. This ties into the idea of using curtailed solar/wind (when supply exceeds grid demand) to drive CO₂ utilization processes. It effectively stores renewable energy in the form of chemical bonds in carbon materials. Regions with very cheap solar could produce carbon products from CO₂ as a new industry (we’ll discuss a Middle East example next). In contrast, traditional CCS often parasitically loads a power plant (making it produce more fossil energy to power the capture, which somewhat undercuts its benefit unless there’s spare clean energy to do the capturing).

• Potential to Offset Other Emissions: Some carbon products can directly offset emissions elsewhere. For example, if CO₂-derived carbon nanomaterials are used to strengthen concrete, you might use less cement for the same strength, thereby avoiding CO₂ from cement production (cement making is a huge CO₂ emitter). Or if carbon fiber from CO₂ is used to lightweight cars or airplanes, it can improve fuel efficiency. These indirect benefits mean CO₂ utilization could have a multiplier effect in reducing emissions across the economy (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon) (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon).

All that said, challenges remain. The molten salt CO₂ conversion is still in relatively early stages. Most demonstrations have been at laboratory scale, producing grams or kilograms of carbon. Scaling up to millions of tons of CO₂ will require significant engineering development. Operating a molten salt electrolyzer continuously at high temperatures (400–900°C typically) brings materials challenges: corrosion of electrodes and reactor components, managing impurities, ensuring consistent product quality, etc., are non-trivial issues. The mentioned review highlights the need for more research on long-term operation and on designing cell configurations that can handle large volumes of CO₂ over time. The process also currently consumes a lot of energy per ton of CO₂. If that energy is not carbon-free, it could negate the benefits; therefore, it’s crucial that these systems run on renewable or zero-carbon power to truly mitigate climate change.

Furthermore, producing huge quantities of carbon raises the question: is there a market for it at the required scale? If we captured just 1% of global CO₂ emissions as carbon (~370 million tons of carbon), that quantity of carbon is enormous – far beyond current markets for things like carbon black or CNTs. However, one can argue that new markets would emerge if carbon materials became cheap and plentiful. For instance, one could envision using carbon materials to replace steel rebar (carbon fiber reinforced polymer rebar), or building entire car bodies from carbon composite, or massive energy storage in carbon-based electrodes, etc. There is also the possibility of geologically storing the carbon itself (e.g., carbon could be buried in old mines or formed into stable carbonates) if there’s excess. The ideal scenario though is to integrate the carbon into the economy such that it stays out of the air permanently in useful form.

Solar Fuels and Materials: A Middle East Opportunity

An intriguing regional case for these new carbon utilization technologies is the sun-rich Middle East. Countries like the United Arab Emirates (UAE) and Saudi Arabia have two things in abundance: CO₂ (from oil and gas production and power generation) and sunshine. They are also actively seeking ways to reduce their carbon footprint and to develop new industries that fit a future low-carbon world (as evidenced by initiatives like Saudi’s Vision 2030 and the UAE’s investments in renewables and hosting of climate summits).

Imagine a large CO₂ conversion facility in a desert region powered by solar energy. During the day, vast solar photovoltaic fields and concentrated solar power (CSP) plants generate cheap electricity (and heat). This energy feeds a molten salt CO₂ electrolysis plant. CO₂ could be captured from nearby sources such as natural gas power plants, refineries, or even directly from the air using solar-powered direct air capture. The CO₂ then gets converted into solid carbon. The output could be graphite, carbon nanotubes, or carbon fibers, which can be used in industries or exported as high-tech materials. The oxygen byproduct could be bottled for medical or industrial use, or potentially used in oxy-fuel combustion at some of those same power plants to further enhance capture (creating a synergistic loop).

The Middle East’s solar potential is enormous – for example, Dubai’s Mohammed Bin Rashid Al Maktoum Solar Park is scaling up to 5 GW of capacity, including 700 MW of solar thermal with 15 hours of molten salt heat storage to deliver power even at night (United Arab Emirates - SolarPACES) (United Arab Emirates - SolarPACES). That kind of installation could provide a steady power input to a CO₂ conversion process around the clock. High temperatures are actually an advantage for molten salt CO₂ capture (running cells hotter can increase efficiency up to a point, though it can also shift the product more toward CO rather than solid carbon if too hot, so there is an optimal range). Places like Saudi Arabia’s Empty Quarter desert or the high solar insolation areas of Abu Dhabi could host “solar carbon farms” that literally harvest carbon from air or flue gas.

This approach could be particularly attractive to Gulf states because it aligns with their strategies:

• Taking advantage of existing infrastructure: They have expertise in handling gases, running large plants, and exporting commodities. Instead of oil, they could export carbon nanomaterials. Some Gulf companies are already researching carbon-based products (for instance, Saudi Aramco has research centers looking into non-metallic materials like carbon fiber for pipelines and vehicles).

• Circular carbon economy: Saudi Arabia in international forums often speaks about a “Circular Carbon Economy” – reduce, reuse, recycle, and remove carbon. Turning CO₂ into products is a centerpiece of that concept, effectively “reusing” carbon in a closed loop.

• Use of cheap energy: Solar energy in the Middle East has achieved record low costs (below 2 cents per kWh in some auctions). This low-cost energy can drive energy-intensive processes like CO₂ electrolysis. Instead of exporting all their solar power via electricity (which has limits due to grid and storage constraints), they can export solar energy in embodied form – first as chemical energy in carbon materials, and potentially as actual shipped products that contain the sequestered carbon.

• Sunlight to stability: It’s almost poetic – using abundant sunlight to take the waste CO₂ from past fossil fuel use and turn it into solid carbon for future technologies. For example, excess CO₂ from an oil refinery could be converted into carbon nanotubes that go into making lightweight electric vehicle parts. In a region that built its wealth on carbon (oil), this is a path to reinventing their economies around carbon tech rather than carbon fuel.

Source: https://fossil.energy.gov/archives/cslf/Projects/AlReyadah.html

One could envision a facility in, say, Abu Dhabi, where CO₂ from a steel plant (Emirates Steel, which already captures some CO₂ for EOR) is instead fed to a molten salt reactor powered by a large adjacent solar farm. The output graphite could be used to manufacture lithium-ion battery anodes locally, supporting a battery industry in the region. Or in Saudi Arabia, CO₂ from a natural gas processing plant could be converted to carbon fibers used for desalination plant equipment or construction materials. The Middle East also has mineral resources (like lithium, magnesium) that could integrate with such processes (for example, producing carbon and magnesium by co-electrolysis of CO₂ and magnesium oxide in molten salt – yielding carbon and magnesium metal, which is another concept being researched).

Moreover, these countries have the capital to invest in large-scale projects and can pilot such new technologies at scale. If successful, it not only helps them meet climate commitments (many have announced net-zero targets around mid-century) but also creates an exportable solution for the world.

Conclusion: Storing Carbon and (actually) Using It

Carbon capture is at a crossroads. On the one hand, traditional CCS – capturing CO₂ and pumping it underground – is finally seeing serious investment and policy support after years of slow progress. Projects like the UK’s new CCS corridor with Eni show that governments are willing to spend billions to build the pipelines and storage sites needed to scale up CCS. This will likely lead to more CO₂ being captured from industrial hubs in the coming decade, which is a necessary step to limit emissions from heavy industries. However, traditional CCS alone has limitations: it doesn’t inherently make money, it depends on carbon prices or subsidies, and its track record is littered with delays and disappointments. Even optimistic scenarios suggest that CCS deployment needs to accelerate far beyond historical rates to meaningfully contribute to climate goals (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change).

On the other hand, new CCU technologies offer a potentially game-changing complement to CCS. By creating valuable outputs – whether oil (in the case of EOR) or, more promisingly, durable materials (in the case of carbon products) – they change the narrative from one of burden to one of opportunity. Particularly, molten salt CO₂ conversion to solid carbon stands out as a technique that directly addresses the economic hurdle. It is a vivid example of innovation born from necessity: scientists turning an age-old chemistry challenge (CO₂ is a very stable molecule) into a solution for climate change, producing some of the most advanced materials known (nanotubes, graphene) in the process. This approach is still young, and it won’t replace the need to reduce emissions or even the need for some pure storage of CO₂ in the near term. But it points to a future where capturing carbon becomes a profitable industry, not just an environmental expense.

In all likelihood, a mix of solutions will be needed. Carbon capture and storage can tackle large volumes of CO₂ from big emitters and will be vital for deep decarbonization in sectors like cement where we might not have better options soon. Meanwhile, carbon capture and utilization can create niches where CO₂ is harvested for value, driving innovation and perhaps capturing the public’s imagination (it’s certainly more exciting to turn CO₂ into jet fuel or car parts than to bury it unseen). As utilization technologies mature, they could take on a larger share of CO₂ mitigation. Governments can help by recognizing and crediting the permanent CO₂ storage achieved in solid products (for instance, giving similar incentives for carbon-to-solid utilization as are given for geological storage).

Ultimately, the “promising future” of carbon capture will likely be one where we do both: we will bury some carbon deep in the Earth to dispose of it safely, and we will transform some carbon into new materials to build the economy of tomorrow. The former treats CO₂ as a waste, the latter treats CO₂ as a resource. Pursuing both avenues increases our chances of reigning in atmospheric CO₂ in time. As the old saying goes, “waste not, want not” – the CO₂ we once thought of as mere waste could become the feedstock for a new industrial revolution in carbon tech. The coming decade will test these ideas in practice. If projects like the UK-ENI CO₂ pipeline show the will to invest in infrastructure, and startups like those producing CO₂-based nanotubes show the way to profitable utilization, together they may finally make carbon capture a widespread reality. The challenge of climate change demands we use every tool available – and now, through human ingenuity, even the very gas causing the problem can be turned into part of the solution.

References:

1. British Geological Survey – “What is carbon capture and storage?” (definition and methods) (Understanding carbon capture and storage - British Geological Survey)

2. IEA – “What is CCUS?” (point source capture and utilization/storage explanation)

3. BGS – Carbon capture techniques (post-combustion, pre-combustion, oxy-fuel) (Understanding carbon capture and storage - British Geological Survey) (Understanding carbon capture and storage - British Geological Survey)

4. Reuters (Venugopalan, 2025) – UK and Eni approve 38-mile CO₂ pipeline (Liverpool-Manchester CCS project)

5. Offshore Technology (2025) – Details on Eni’s UK CCS pipeline and UK CCS investment plans

6. BGS – CO₂ pipelines and EOR in the US (5,800 km pipelines for CO₂-EOR)

7. Reuters (Stanway, 2023) – Explainer on carbon capture status: 49 Mt/year, 78% used for EOR (Explainer: Why carbon capture is no easy solution to climate change | Reuters) (Explainer: Why carbon capture is no easy solution to climate change | Reuters)

8. Reuters (Stanway, 2023) – High costs of CCS ($15–120/ton) and need for subsidies or oil revenue (Explainer: Why carbon capture is no easy solution to climate change | Reuters) (Explainer: Why carbon capture is no easy solution to climate change | Reuters)

9. Nature Climate Change (Jewell et al., 2024) – Study on CCS deployment vs climate targets (88% project failure rate historically) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change) (Feasible deployment of carbon capture and storage and the requirements of climate targets | Nature Climate Change)

10. Reuters (Gardner, 2023) – Petra Nova project history: $1B cost, 1.4 Mt/year, shutdown and restart, used for EOR (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters) (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters)

11. Phys.org (2023) – “Overview of CO₂ capture and electrolysis in molten salts” (summary of RSC review, advantages of molten salt CO₂ conversion)

12. Zhu et al. (Industrial Chemistry & Materials, 2023) – Molten salt CO₂ electrolysis review (conversion efficiency >80%, current efficiency >90%, need to solve corrosion & scaling issues)

13. CarbonCorp – Company website (CO₂ to carbon nanotubes via molten salt Genesis Device®) (Transforming CO2 Into Valuable Carbon Nanomaterials - Carbon)

14. SkyNano – Company description (transforming CO₂ from industrial streams into solid carbon nanotubes, applications in batteries, tires, coatings, etc.) (SkyNano | Transform CO2 into advanced carbon materials)

15. Renewable Carbon News (2023) – UP Catalyst molten salt CCU project (CO₂ to carbon nanomaterials and graphite, salt reuse) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News) (Consortium Introduces Molten Salt Regeneration System for CCU - Renewable Carbon News)

16. ScienceBlog (Chalmers Univ., 2024) – Study finding CCS not on track for Paris targets (needs acceleration, gap between current capacity and needed scale) (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com) (Carbon Capture and Storage Falls Short of Climate Targets, Study Finds - ScienceBlog.com)

17. BGS – Geological storage permanence (IPCC says >99% retained over 1000 years in good sites)

18. Reuters (Gardner, 2023) – Criticism of CCS (Petra Nova missed targets, CCS could prolong fossil fuel dependence) (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters) (Carbon capture project back at Texas coal plant after 3-year shutdown | Reuters)

19. SolarPACES (2024) – Dubai 700 MW CSP project with 15-hour molten salt storage (example of solar resource for 24/7 power)