All paths to getting CO2 emissions down to zero still won’t be enough to keep global warming to 1.5 degrees Celsius. I mentioned this a few months ago: even if all worldwide emissions stopped tomorrow, there’s already too much CO2 in the atmosphere. We need to get down to negative emissions, which means capturing CO2 from the air and sequestering it.
Fortunately, there are biological and technological ways of doing this. Biology captures carbon from the air and stores it in wood, soil, or biomass which can be sent to the depths of the ocean where it’s destined to become rock. There are catalyst and membrane technologies that separate and concentrate CO2 produced by industrial processes and direct air capture (DAC) technology that go after the tiny but troublesome concentrations of CO2 in the atmosphere itself. Climeworks is one company that builds DAC machines.
The trouble is, once you have the CO2, what do you do with it? Right now, the whole carbon-capture process is super expensive. On a P/L statement, it looks like a big cost without an immediate tangible benefit—an expense without any sellable output. Not too palatable.
So, can you sell the CO2? Big commercial customers for CO2 include the oil fracking industry, and producers of fuels and fizzy drinks. Using expensively captured CO2 for oil extraction seems self-defeating, and putting the fizz into fizzy drinks is noble, but ends up carbon neutral, not carbon negative.
Some people get excited by the removal process itself and are willing to pay to have it pumped deep underground for (hopefully) long-term storage. This will likely need to be paid for directly by governments, or through government-mandated or corporate-inspired carbon offset markets. But until things get especially dire, I fear the numbers will be too small to drive CO2 capture at scale.
To get to negative emissions on a global scale, we need lots of people around the world capturing and sequestering CO2. That includes people who aren’t especially attached to the problem of climate change.
This has always been the idea behind Tesla: to make a real difference, lots of people need to buy electric cars—not necessarily because they’re eco-friendly, but because Teslas are so awesome that you “selfishly” want to own one of those fancy electric cars. Eco-friendliness is icing on the cake.
When it comes to re-capturing carbon from the air, we can encourage “selfish” participation by making the output visibly useful. We need to find something to do with the carbon that’s commercially viable—something that makes the effort and resources worthwhile to people who aren’t single-minded about sustainability.
Ideally, we could turn the carbon into a durable good that people want. Aether takes this approach by compressing the carbon into diamonds to create lines of responsibly sourced jewelry. It’s a wonderful use case, but ultimately we can’t bling our way out of a climate crisis, although it could be pretty fun trying.
I’m most interested in carbon-negative building materials, like drywall and concrete.
The reason is that they have potential for mass adoption on a sufficiently large scale to drive down the price of DAC and other carbon capture technologies. Demand drives increases in production capacity. Those increases in turn drive down costs via the phenomenon characterized by Wright’s Law. Lower costs then feed back into a cycle of more demand, more capacity, and still lower costs.
This is obvious in the renewable energy sector, which has seen the costs of solar and wind generation drop 90% during the last 20 years as production capacity soared, which drove prices down, which increased demand. Wind and solar are now the cheapest energy to add to the grid. As a result, 2020 saw another record expansion in renewable energy: 260GW (despite a pandemic and global recession).
That’s the kind of scale we are going to need for carbon-negative technologies, and building materials are a prime candidate for achieving it: we do a lot of building and will do even more in the future. The production of buildings also has other environmental issues that might be helped by these new materials, from the damage caused by unsustainable sand mining to the energy required and direct CO2 release in cement production.
There are regulatory obstacles to be overcome with new building materials, even after getting the products right. This is especially true in decentralized countries like the United States, but as we have seen during these Covid times, change can happen quickly when it’s important. An exciting aspect of carbon-negative building materials is how carbon value might drive rapid adoption with relatively light and layered regulatory tailwinds.
Imagine, for instance, a carbon offset credit that partially offsets the cost of using a carbon-negative concrete (cement + aggregate). Or imagine if towns under pressure to reduce their carbon footprint provided faster building approvals or lower permitting costs to builders using carbon-negative materials. The resulting footprint reductions would flow upward to state and national levels, and help countries achieve carbon reduction goals. Regulations, costs and incentives could quickly align, driving the scale we need to really go negative on CO2.
If I had the right expertise and a good plan, I’d start a company in this area in 2021. So if you’re already working on this, I’m an interested investor. Get in touch via firstname.lastname@example.org.