Growing concerns about climate change are intensifying interest in advanced technologies to reduce emissions in hard-to-abate sectors, such as cement, and also to draw down CO2 levels in the atmosphere. High on the list is carbon capture, utilisation and storage (CCUS). To better understand the possible role of CCUS, we looked at current technologies that could accelerate CCUS adoption.
Cementing in CO2 for the ages
New processes could lock up CO2 permanently in concrete, “storing” CO2 in buildings, pavements, or anywhere else concrete is used. This could represent a significant decarbonisation opportunity for example, consider precast structural concrete slabs and blocks. They could potentially be made with new types of cement that, when cured in a CO2-rich environment, produce concrete that is around 25% CO2 by weight.
There’s a CO2 bonus available here as well: cement used in this curing process has a lower limestone content. That’s significant, since baking limestone (calcination) to make conventional Portland cement releases about 7% of all industrial CO2 emissions globally.
A second concrete process involves combining the aggregates with cement to make concrete (think cement mixers). Synthetic CO2-absorbing aggregates (combining industrial waste and carbon curing) can be formed to produce this type of concrete, which is 44% CO2 by weight. We estimate that by 2030, new concrete formulations could use at least 150 million tonnes of CO2 per year.
Carbon-neutral fuels for jets and more
Technically, CO2 could be used to create virtually any type of fuel. Through a chemical reaction, CO2 captured from industry can be combined with hydrogen to create synthetic gasoline, jet fuel, and diesel. The key would be to produce ample amounts of hydrogen sustainably.
One segment keen on seeing synthetics take off is the aviation industry, which consumes a lot of fuel and whose airborne emissions are otherwise hard to abate. By 2030, we estimate, this technology could abate roughly 15 million tonnes of CO2 annually.
The biomass-energy cycle: CO2-neutral or even carbon-negative
Bioenergy with carbon capture and storage (BECCS) relies on nature to remove CO2 from the atmosphere for use elsewhere. Using sustainably harvested wood as a fuel renders the combustion process carbon neutral. (Other CO2-rich biomass sources, such as algae, could be harvested, as well.)
Biomass fuel combustion could become carbon negative if the resulting CO2 emissions were then stored underground or used as inputs for industrial products, such as concrete and synthetic fuel.
The degree to which BECCS can yield negative emissions, however, depends on a number of intermediate factors across the life cycle. These factors include how the biomass is grown, transported, and processed — all of which may “leak” CO2.
Superstrong, superlight carbon fibre is used to make products from airplane wings to wind-turbine blades, and its market is booming. The price of the component carbon is high (more than $20,000 per tonne), so manufacturers would love to have a cheaper, CO2-derived substitute. Moreover, the volume of CO2 used could become significant if cost-effective carbon fibre could be used widely to reinforce building materials.
A number of pilot projects in the works focus on cracking the tough chemistry involved, but a commercially viable process appears to be perhaps a decade or more away.
By 2030, we believe, the contribution to CO2 abatement would be 100,000 tonnes of CO2 a year.
Storing carbon in your mattress?
CO2 could substitute for fossil fuel–based inputs in plastics production. The combination of technical feasibility and high interest from environmentally aware consumers has attracted the attention of major chemical companies, which are testing a range of CO2-based plastics for widespread use.
Green polyurethane — used in products such as textiles, flooring for sports centers, and, yes, mattresses — is in the early stages of commercial rollout. Storing carbon in green plastics would sequester it indefinitely.
By 2030, we estimate, plastics could abate a modest but growing 10 million tonnes of CO2 annually.
The CCUS opportunity is a natural extension of something that occurs every day in the global economy: the collection and disposal of waste and the transformation of some of it into higher-value products and materials.
To make the economics work and to encourage further technological innovation, incentives and supportive regulatory frameworks will be necessary. If they come, CCUS can help support the transition to a low-carbon economy.
Krysta Biniek is an associate partner in McKinsey’s London office; Kimberly Henderson is a partner in Washington DC office; Matt Rogers is a senior partner in the San Francisco office; and Gregory Santoni is an associate partner in the Houston office.