Trapping Carbon in Bioplastic

Transcript

INTRO

According to the Intergovernmental Panel on Climate Change’s latest scientific report, released today in 2022, the impacts of climate change are appearing faster than expected. Already, these dangers are overwhelming the speed at which nature, of which humanity is part, can adapt. The increasingly terrifying natural disasters we’re seeing will lead to the most severe population displacement the world has ever seen. More species will be driven extinct, even faster than they are being wiped out now as we power the sixth mass extinction event, faster than we’ve ever seen before. As we irreversibly change the planet, the question of great interest to me is, will we leave a habitat for ourselves, or will we go the way of those species we’ve already wiped from existence?

PROBLEM

It is widely known that, to avert the worst crisis situation, we must remove carbon dioxide, methane, and other greenhouse gases from the atmosphere. For many carbon-intensive industries, carbon capture, utilization, and sequestration, or CCUS, will be a stopgap measure before cleaner processes are developed. For the hard-to-abate sectors like heavy industry where there may be few options for carbon emissions reductions within the processes themselves, CCUS will be critical to decarbonization. However, according to the International Energy Agency (IEA)’s Tracking Clean Energy Progress (TCEP) reports, CCUS technologies are off track from their Net Zero Emissions by 2050 Scenario (NZE) pathway [1].

Let’s talk about the power of policy for a moment. Based on what we’ve seen with wind power, solar photovoltaics, and batteries, climate policy is essential to decarbonization. Good policy has the power to jumpstart global markets, plummeting the costs of new technologies and shifting markets to low-carbon alternatives [2].

While policies like carbon pricing are pushing long-term decarbonization, these schemes are not very strong yet, and companies mostly continue to view dealing with carbon emissions as an expense [3]. And indeed, carbon capture can be costly, especially as processes produce less concentrated gas streams such as in cement production and power generation [4]. According to engineers and researchers, we now need a price breakthrough in CCUS rivalling that of wind, solar, and batteries. One way of unleashing this technology’s potential by market forces is to find creative ways of converting captured carbon into valuable products. In other words, we might be able to get CCUS adoption on track to net zero by 2050 if companies can turn a profit by capturing carbon.

AIRCARBON

One such company turning captured carbon into valuable products is Newlight Technologies, based out of Huntington Beach, right here in California. Twenty years in the making, their innovation uses microorganisms from the ocean to break down excess methane-containing greenhouse gas emissions. In nature, as the gases are dissolved in saltwater, the organisms eat methane and carbon dioxide as food and naturally produce a biomaterial called polyhydroxybutyrate (PHB), one of the polyesters known as polyhydroxyalkanoates (PHAs). Since PHB is meltable, it can then be used as a replacement for synthetic plastic, fiber, and leather in a wide variety of applications. Newlight has successfully optimized, replicated, and scaled this process up in their bioreactors on land to sustainably produce what they call AirCarbon from—you guessed it—air and methane-based carbon.

When microorganisms, also called biological catalysts or biocatalysts, are exposed to unfavorable conditions such as a carbon-excessive environment with limited nutrients, they begin to produce PHB as a natural carbon and energy storage technique [5]. According to the Environmental Protection Agency, Newlight’s innovation lies in their development of a biocatalyst that does not “turn itself off” after producing a certain amount of the polymer. To achieve this, Newlight disables “the negative feedback receptors on PHA polymerase, the central polymer production enzyme in the biocatalyst,” enabling continued polymerization “significantly beyond previous maximum limits.” Thus, the process “generates a yield of nine kilograms of polymer for every one kilogram of biocatalyst—nine times more material compared to previous technologies” [6]. Newlight claims the microorganisms can even out-compete the production of oil-based plastics such as polypropylene and polyethylene [7].

IMPACTS

Unlike most unsustainable plastics today which are derived from petrochemicals (derived from oil and gas), PHB is a particularly exciting polymer because it is both bio-derived and biodegradable. This means it is not only created entirely from raw materials found in nature, but also able to be broken down by living organisms like bacteria [8]. In effect, this carbon capture technology tackles two problems in one solution: (1) When using renewable power, AirCarbon production is a carbon-negative process, sequestering more carbon than emitted to make it. (2) If the material ends up in the ocean, it naturally degrades within a year; as Newlight puts it, “because AirCarbon is PHB and PHB is natural, nature knows what to do with it,” and microorganisms can consume it as food [9].

There is much more work to be done to solve the climate challenge, however. According to physicists, the current supply chain for AirCarbon is far from big enough to absorb the 15+ tons of CO2 emitted per capita annually in the United States or the greenhouse gas emissions from power plants alone. So, AirCarbon is an “every little bit helps” part of the solution [10].

We’re a tiny part of the solution, too. If AirCarbon sounded familiar to you, that’s right, your Cal Poly reusable cutlery is made of AirCarbon!

OUTRO

What do you think of PHB’s potential as a carbon capture technology? Should we even be trying to replace other plastics, or should we be reducing plastic use entirely, or both? How has your experience been with using AirCarbon utensils? Jump in the comments and let me know. Thanks so much for watching, and I’ll see you in the next one.

REFERENCES

1. Tracking Clean Energy Progress – Topics. (n.d.). IEA. https://www.iea.org/topics/tracking-clean-energy-progress
2. Fork, D., & Koningstein, R. (2021, June 28). Engineers: You Can Disrupt Climate Change. IEEE Spectrum. https://spectrum.ieee.org/engineers-you-can-disrupt-climate-change
3. University of Houston Energy Fellows. (2021, January 27). We Can Capture Carbon, But What Then? Turning A Profit Will Be Key. Forbes. https://www.forbes.com/sites/uhenergy/2021/01/27/we-can-capture-carbon-but-what-then-turning-a-profit-will-be-key
4. ‌Baylin-Stern, A., & Berghout, N. (2021, February 17). Is carbon capture too expensive? – Analysis. IEA. https://www.iea.org/commentaries/is-carbon-capture-too-expensive‌
5. McAdam, B., Brennan Fournet, M., McDonald, P., & Mojicevic, M. (2020). Production of Polyhydroxybutyrate (PHB) and Factors Impacting Its Chemical and Mechanical Characteristics. Polymers, 12(12), 2908. https://doi.org/10.3390/polym12122908
6. Presidential Green Chemistry Challenge: 2016 Designing Greener Chemicals and Specific Environmental Benefit: Climate Change Awards. (2016, May 31). US EPA. https://www.epa.gov/greenchemistry/presidential-green-chemistry-challenge-2016-designing-greener-chemicals-and-specific
7. NewLight Technologies. (2014). Plastic-Alternative Biomaterial Inspired by Ocean Microorganisms — Innovation. AskNature. https://asknature.org/innovation/plastic-alternative-biomaterial-inspired-by-ocean-microorganisms/
8. Polymer Solutions News Team. (2018, January 18). Polyhydroxybutyrate: An Exciting Biodegradable Polymer. Polymer Solutions Incorporated | Materials Science Research & Innovations. https://www.polymersolutions.com/blog/polyhydroxybutyrate/
9. AirCarbon. (n.d.). Newlight Technologies, Inc. https://www.newlight.com/aircarbon
10. Laskow, S. (2014, January 2). This plastic is made out of carbon sucked from the air. Grist. https://grist.org/living/this-plastic-is-made-out-of-carbon-sucked-from-the-air/