Why Carbon Capture and Sequestration is Essential, but so Hard?

We’re falling short on climate goals — and fast. Even if we halted new fossil fuel projects today (we won’t), we’d still blow past the 1.5°C target. That’s where carbon capture and sequestration (CCS) comes in: not as a silver bullet, but as one of the only tools we have left for the hardest-to-decarbonize sectors and climate change mitigation.

We Are Not on Track

By any metric, we are nowhere near meeting our Paris Agreement climate targets, —pursuing efforts to limit temperature rise to 1.5°C and to keep it well below 2°C compared to pre-industrial levels.

• According to the IPCC, global surface temperatures are already over 1.2°C above pre-industrial levels (based on the 10-year average from 2014 to 2023).
• IPCC indicates that crossing the 1.5°C threshold risks unleashing far more severe climate change impacts, including more frequent and severe droughts, heatwaves, and rainfalls.
• In 2024, the World Meteorological Organization (WMO) reported that we hit 1.55°C. But don't worry — we're supposed to focus on 10-year averages, so technically we're not officially in crisis mode yet (note the sarcasm).

Here's the hard truth:

According to the IPCC, projected CO₂ emissions from existing and planned fossil fuel infrastructure will blow past the remaining carbon budget for 1.5°C — and nearly exhaust it for 2°C.

Even if we stopped approving new fossil fuel infrastructure today — which, let’s be honest, isn’t happening (in fact, the opposite is true) — we’re already locked into a difficult situation.

To put this in perspective:

In How the World Really Works, Vaclav Smil reveals that global fossil carbon demand is more than twice the mass of all the water humans consume. That's the magnitude we're dealing with.

And the challenge deepens:

• The average lifespan of today's fossil fuel power plants is 40–50 years.
• Critical industries like cement, steel, agriculture, aviation, shipping, and chemical production remain extremely difficult to decarbonize at scale.

Unless we make fundamental lifestyle changes (a well-known complex social and political challenge), we must find a way to decarbonize these industries. The dual challenges we face are decarbonizing industrial processes and lowering CO₂ concentrations to pre-industrial levels.

This is where CCS transforms from a "nice-to-have" into an absolute necessity, despite its significant cost.

What is CCS?

Carbon Capture and Storage (CCS) is a suite of technologies that does exactly what it sounds like: It captures carbon dioxide (CO₂) emissions from industrial or energy-related sources and stores them deep underground to prevent them from entering the atmosphere.

This is not some far-off sci-fi concept — we’ve been doing this for decades. In fact, we know how to capture and store CO₂ safely, at scale, and across a range of industries.

1. Carbon Capture Technologies

Carbon capture usually happens at the source, before emissions even leave the facility. Common technologies include:

• Post-combustion capture: The most widely used method, especially in power plants. CO₂ is stripped from flue gas after fossil fuels are burned, typically using a chemical solvent like amine.
• Pre-combustion capture: CO₂ is removed before the fuel is burned — for example, by gasifying coal or natural gas into a mix of CO₂ and hydrogen.
• Oxy-fuel combustion: Fossil fuels are burned in pure oxygen, producing a concentrated CO₂ stream that’s easier to capture.

2. Carbon Sequestration Technologies

Once CO₂ is captured, the next step is permanent storage — a.k.a. sequestration. This happens in a few ways:

• Geological storage: The gold standard. CO₂ is injected into deep (kilometers deep) underground formations where it’s trapped under layers of impermeable rock.
• Enhanced oil recovery (EOR): CO₂ is injected into oil reservoirs to boost oil production. This has been done commercially since the 1970s, especially in the U.S., but the goal today is to do it in a way that results in net-negative emissions.
• Mineral carbonation: CO₂ reacts with certain minerals to form stable carbonates — essentially turning the gas into rock.
• Bioenergy with Carbon Capture and Storage (BECCS): Combines biomass (which absorbs CO₂ during growth) with CCS to generate energy (in the form of biofuels) and remove CO₂ from the atmosphere at the same time.

Is CCS Expensive?

Expensive, yes — but cost-effective when compared to the consequences of inaction.

As economists emphasize, climate policy should focus on maximizing net benefits. When comparing the cost of mitigation (like CCS) against the cost of unchecked climate change, CCS makes sense and becomes critical, and irreplaceable.

The balance is delicate:

• Too little CCS, and we miss our climate targets.
• Too much CCS, and mitigation becomes needlessly expensive compared to alternatives.

The numbers tell a stark story:

• The International Energy Agency (IEA) suggests CCS should account for 9% of cumulative global emissions reductions (see next figure).
• The IPCC says limiting warming to 1.5°C will require removing about 100 gigatons of CO₂ by 2050.
• Yet, even if every proposed CCS project were built (which is being overly optimistic), we'd only reach 12 gigatons (Global CCS Institute).

In other words, to stay on track, we’ll need to inject 10 to 20 billion tonnes of CO₂ per year by mid-century. Today? We’re injecting just about 40 million tonnes per year.

That’s a 250× scale-up. And we’re nowhere near on pace.

👉 In short: We face an orders-of-magnitude problem.

Like transmission lines for renewables, grid-scale storage, and nuclear, we are astonishingly underinvesting in critical infrastructure compared to the scale of the challenge.

What We Worry About: Permanence, Risk, and Scale

One of the biggest concerns — from scientists and the public alike — is permanence:

What if the CO₂ leaks back out?

It’s a valid concern — and not a new one. We've dealt with similar risks for decades with natural carbon sinks like forests, where trees can burn or decay, releasing CO₂ back into the atmosphere.

And let’s be pragmatic: if CO₂ leaks from a storage site, it simply returns to where it started — the atmosphere. In that sense, it’s not catastrophic, but it does undermine the whole point of storing it in the first place.

But, when it comes to long-term security, geological sequestration — storing CO₂ deep underground in secure rock formations — is hands down our best bet.

• The IPCC reports that properly selected and managed sites are very likely to retain more than 99% of stored CO₂ over 100 years.
• According to my own research (publication coming soon!), even under worst-case scenarios, storage security could approach 99.9%.

Bottom line:

If we're serious about climate change, geologic sequestration isn't Plan B — it's the only viable Plan A.

And it doesn't stop there.

Given how likely it is that we’ll overshoot 1.5°C, and possibly even 2.0°C, we’ll eventually need to remove CO₂ directly from the atmosphere to bring temperatures back down. That’s where technologies like Direct Air Capture (DAC) and other carbon dioxide removal (CDR) methods come in.

And if that sounds challenging, it is:

• Air has CO₂ at only ~420 parts per million.
• Capturing it from the air is hugely energy-intensive.

Therefore, it's smarter to start now — capturing CO₂ from point sources — to drive down costs and improve efficiency before direct air capture becomes unavoidable. And most importantly, delays will force higher reliance on CDRs (including DAC) later, making decarbonization more expensive.

Long story short, point-source capture now reduces the burden on DAC later.

The Tricky Part: Can Removing CO₂ Cool the Planet?

We know adding CO₂ warms the planet. But we don’t fully understand how quickly removing it will cool it down, or whether it will reverse extreme climate impacts on the same timescale.

Translation: faith will have to be part of the plan.

Other geoengineering options — like:

• Modifying oceans to absorb more CO₂
• Spraying aerosols into the stratosphere to reflect back more sunlight

— come with huge unknowns and massive risks.

Messing with Earth's systems more than we already have? Sounds like a terrible idea.

Compared to those gambles, CCS is a mature, proven, and much safer approach.

What Are We Missing?

Let's be clear: We don't have a technological problem.

We've been capturing CO₂ and injecting it underground for over 50 years (mainly to boost oil recovery).

The real issue? Scaling CCS fast enough, cheap enough, and across the right sectors.

Yes, cost is an issue. But as I mentioned before — and this is crucial — the cost of CCS pales in comparison to the future costs of inaction.

The fundamental challenge is that:

• Politicians
• Public decision-makers

operate with very high discount rates. They severely undervalue future outcomes.

Climate change isn't some distant threat. It's unfolding now.

Why Policy Matters (a Lot)

Climate action faces a classic public goods dilemma:

• Private companies lack sufficient incentives to act. Why? Because the benefits of reducing emissions are shared globally, but the costs are borne locally. This creates a massive free-rider problem.
• Governments must take the lead, but political will is often missing, especially when the economic (and political) costs are immediate and the climate benefits are long-term and globally dispersed.

That’s what makes CCS the most challenging climate technology to scale. Unlike solar, wind, or EVs, CCS isn’t consumer-driven. It relies entirely on policy, regulation, and long-term planning — all of which are increasingly fragile in today’s geopolitical landscape.

Today’s trend? Deregulation, nationalist trade barriers, and weakened multilateral cooperation. Not exactly the fertile ground you need for a globally coordinated carbon pricing system.

Let’s make a quick comparison to understand why the economics are challenging here.

Compare this to the ozone layer crisis a few decades ago. We banned CFCs — the hazardous compounds destroying the ozone layer — under the Montreal Protocol, and it worked. Why? Because the cost-benefit math added up for the major emitters.

• The cost of banning CFCs was relatively low.
• The human health and environmental benefits (in dollar terms) were immediate and local — fewer cancer cases, less eye disease, better agriculture.

In plain English, unilateral action made economic sense, so countries acted. But with climate change, the logic doesn’t hold:

• The wealthiest countries, responsible for the bulk of emissions, face less immediate damage and have more resources to adapt.
• Meanwhile, developing nations, with fewer emissions, suffer the harshest consequences — droughts, floods, food insecurity, and displacement.

The incentives for unilateral action are, to say the least, weak. Wealthy countries have little reason to invest heavily in mitigation when most of the benefits — avoiding the worst climate impacts — go to developing nations.

Without a strong, enforceable policy, the market alone simply won’t fix this.

But, what are some policy solutions? Here are a couple:

• Cap-and-trade systems: These set a firm limit on total CO₂ emissions and allow companies to buy and sell permits to emit within that cap. The cap gets lower over time, tightening the emissions budget while letting the market find the most cost-effective reductions.
• Carbon taxes: A more straightforward approach: put a price on every ton of CO₂ emitted. This sends a clear economic signal — polluting becomes more expensive, and clean alternatives become more competitive.

Quick side notes:

Carbon taxes are superior to cap-and-trade systems by almost every metric. But hey, don't let the perfect be the enemy of the good — with the right tweaks, both can work.

There have been multiple policy proposals, but in my opinion, the one that makes the most sense is the Carbon Takeback Obligation (CTBO) proposed by Myles Allen. You can find the paper here: https://iopscience.iop.org/article/10.1088/1748-9326/aca4e8.

The State of Play: Some Good News...Sort Of

• The European Union launched a Carbon Border Adjustment Mechanism (CBAM) — essentially a carbon tariff on carbon-intensive imports.
• The United States offers tax incentives for capturing and sequestering CO₂ (yes, still holds).
• Major CCS hubs are being announced in Saudi Arabia, Indonesia, Denmark, and the United States.
• The UNFCCC is developing a marketplace for trading emission reduction credits.

But...

• These initiatives remain mostly bilateral, local, and lack standardization.
• The Paris Agreement is voluntary — it's not legally binding (back to the free-rider problem)
• Global cooperation is weakening, making large-scale coordination increasingly difficult.

The Bottom Line

Innovation alone won’t save us — not without a meaningful price on carbon. But without true global cooperation, even carbon pricing can backfire, pushing investments to countries with weaker regulations and making the problem worse.

Climate change is the ultimate collective action challenge — and there’s no opting out. Either we all play, or we all lose.

In other words: It's complicated. It's messy. It's urgent.

And CCS remains a critical part of this imperfect, but necessary, solution.