How Carbon Removal Becomes Cheap
Glen Meyerowitz, Founder & CEO of Clairity Technology, November 28, 2022
After graduating from Yale, I worked at SpaceX to revolutionize space travel and help make humanity a multiplanetary species. Then, at TuSimple, I developed safety critical systems for autonomous vehicles. I next led engineering efforts at the UCLA Biodesign program to create novel medical technologies to improve patient care and outcomes. My passion is working with smart people to solve technically challenging problems so that we can create a better world.
Now, it’s time to go all in to advance solutions to fight climate change – specifically in the field of carbon dioxide removal (CDR).
Humans have emitted over 1.4 trillion tons of carbon dioxide (CO2) into the atmosphere since the start of the industrial revolution and we continue to emit approximately 40 billion tons (gigatons) of CO2 every year. In the time it takes you to read this, humans will emit another 100,000 tons of CO2. The impact this has on our planet is self-evident and drastic steps need to be taken to reduce the harm that increasing levels of CO2 in the atmosphere have on our planet.
Decarbonization is the single most important step to reduce this harm. Collectively, we need to emit less CO2. Decarbonization involves decreasing the consumption of fossil fuels and increasing our reliance on alternative energy sources, like solar, geothermal, and nuclear. Decarbonization can also include driving an electric car, flying less, installing a heat pump in your home, and more. But what about all the CO2 that has already been emitted and remains in the atmosphere? The CO2 we emit today (and yesterday!) will still impact our planet for centuries to come.
The United Nations Intergovernmental Panel on Climate Change (IPCC) estimates that between 10 to 20 gigatons of carbon dioxide removal (CDR) will be required annually by 2050, with increased removal capacity by 2100, to limit warming to 2°C.
We need gigaton solutions for gigaton problems.
What Is Carbon Dioxide Removal?
Carbon dioxide removal (CDR) refers to approaches that remove CO2 from the atmosphere. There are many different approaches to CDR, ranging from planting billions of trees, to ocean acidification, to biomass and biochar technologies, to direct air capture (DAC) where massive fans blow air over chemicals that capture CO2. We analyzed the options, along with the pros and cons of each, to determine the best path forward. In doing so, we relied on a first principles framework that guides all the decisions we make:
Can a specific approach realistically remove the necessary billions of tons of CO2 per year?
How can we minimize the number of kilowatt-hours required to remove one ton of CO2?
If we say that we removed one ton of CO2, can we prove it?
If we remove one ton of CO2, is it out of the atmosphere for years, centuries, or millennia?
These principles shaped nearly a year of research, technical development, engaging with experts in energy and climate tech, and understanding what already exists in the larger landscape. The solution we landed on involves a novel method of DAC of CO2. We then formed Clairity Technology and are excited to advance and scale our operations.
The Clairity Way
Our unique approach involves performing DAC to generate dilute CO2 streams. Alternative approaches to CDR generate high-purity CO2 streams, which match industrial standards that are over a century old. We do not believe that blindly adhering to old standards is the way to spur innovation. Instead, Clairity is setting CDR standards for the 21st century and beyond.
Clairity systems use large fans that blow air over a chemical media to selectively capture CO2 from the air. Once captured, we apply low energy to regenerate the chemical media and release the CO2, before it is sequestered. While we are not the only company developing DAC solutions, Clairity will be the first to bring it to scale in a cost-effective manner with the lowest required energy intensity.
The capital expense (capex) of our system is lower than alternatives as the Clairity process does not require vacuum systems or pressure vessels to prevent air impurities from mixing with the CO2 stream. By streamlining the DAC process, we are able to utilize standard components for construction, significantly lowering manufacturing costs while decreasing future maintenance costs. The operating expense (opex) is lower too because less energy is required to generate a dilute CO2 stream. These factors together allow us to create technologies and systems that can scale more quickly and at a lower cost than more complex CDR solutions.
The chemical media we select plays a critical role in overall system performance. Different chemicals will capture different amounts of CO2, degrade at different rates, and have different unit costs. Clairity understands the sensitivity of each parameter in the optimization of our DAC technology, allowing us to create the most cost-effective solution (which may be different than the most volumetric- or weight-effective solution). Avoiding expensive and unstable chemical sorbents is critical to scalability and low energy intensity.
Input energy is the primary factor driving system opex. From a first principles perspective, the energy required to generate a dilute CO2 stream is less than that to generate a high-purity CO2 stream. The change in Gibbs free energy can be calculated as ∆G = -RT ln(pCO2 / p), where pCO2 is the partial pressure of CO2. The larger the change in CO2 concentration, the larger the required energy. The figure below shows some of these values for ranges of CO2 concentration. Going from air (approximately 400 ppm CO2) to a dilute stream requires significantly less energy than producing a final product that is >98% pure CO2.
The net energy intensity for direct air capture depends on more parameters than just the change in Gibbs free energy. For instance, high-purity systems will require vacuum pumps to remove air from the reactor vessel before regeneration occurs. Vacuum pumps require power to operate, and some estimates show that a vacuum pump system consumes up to 5% of a system’s total energy. Additionally, a vacuum chamber must be used so that the reactor does not buckle and collapse while under vacuum. This will require constructing the reactor vessel from steel and concrete. Dilute DAC plants, such as those being developed by Clairity, do not require expensive steel but instead can be constructed from low-cost lumber. For a small system, the margin cost of a steel reactor vessel compared to a reactor vessel made from lumber will be relatively modest. However, we expect that the construction cost savings for a dilute DAC system will save hundreds of millions of dollars, or more, at gigaton scale.
The carbon removal industry has a total market size of $1T by mid-century. Currently, demand for CDR far outstrips supply.
Payment for carbon removal comes from both the private sector and governments. Private companies, like Microsoft, Stripe, Alphabet, Shopify, Meta, McKinsey, and more, are all purchasing carbon removal using either their own platforms or advanced market commitment (AMC) bodies, like Frontier. These private companies have combined to provide approximately $1B in funding and AMC for future carbon removal purchases. While significant, this is a drop in the bucket for what is needed if DAC and other forms of CDR are to be impactful. The private sector cannot carry this burden indefinitely.
The Inflation Reduction Act (IRA) became law in August 2022 and allocates nearly $370B toward climate investments. One of the largest winners is the carbon removal industry through the codification of enhanced 45Q tax credits. The IRA provides up to $180 / tCO2 in tax credits for CO2 that is removed by direct air capture and sequestered in underground storage.
Where We Stand
Clairity has taken the first steps on its mission and has a multi-year roadmap for us to achieve our goals. The need is great and it is matched by the will to develop solutions. The size and complexity of the problem is too large for any one person, team, company, or country to solve alone. We are proud to be a part of the larger endeavor to create a more livable planet.
We are actively working to build our first pilot plant to capture 100 tCO2 / year. Following that, we will start rapid iteration to decrease the energy intensity and improve material properties. This will involve heavy investments in material science and systems engineering to optimize performance. We will simultaneously scale and build more DAC plants to improve our learning rate and capture increasing amounts of CO2.
We have a badass team of scientists and engineers working on solutions to these problems. If you want to join our team in technical or nontechnical roles, support our goals, or learn more, please reach out to Glen Meyerowitz, firstname.lastname@example.org.
Gigaton scale, here we come!!