Carbon Fixation

It is common practice for companies in the electronics sector to publish annual environmental reports. These reports can be very enlightening. After all, they represent a story about a given company in a situation in which the subject has lots of incentives to make themselves look as good as possible. Yet, companies often make remarkable disclosures in these reports despite the incentives to burnish their image in them. In 2024, for example, Google published a sustainability report that showed the company’s carbon footprint had increased around 48 percent.

The climate emergency is exactly that–an emergency. But, critical environmental thinking about digital technologies should be cautious about the risks of focusing on carbon and the climate emergency to the (near) exclusion of other environmentally problematic impacts of the sector. I have been using the term ‘carbon fixation’ to think about these risks.

I started thinking about this term via some commentary by others on what they called sustainability myopia. It’s a useful metaphor, but it also brings some unsavoury ableist connotations about sight with it. I was looking for a similar metaphor or analogy and landed on carbon fixation which I like in part because of its double entendres with biological and technological processes and fixation’s synonyms such as ‘obsession’ and ‘mania’. If it needs to be said, carbon fixation is not about denying the climate emergency. Instead, it’s a way to think about how framing of one environmental problem, such as the global climate emergency, can end up having unintended consequences for framing and acting on other environmental problems associated with the electronics sector. One might ask, for example, what gets de-emphasized or lost altogether when carbon pollution is the main or only pollution problem understood to arise from an industrial sector such as electronics manufacturing? To get a sense of that, let’s take a dive into a recent environmental report from TSMC, one of the world’s most important semiconductor manufacturers.

Like many companies, TSMC pays attention to its greenhouse gas (GHG) emissions. On page 102 of the company’s environmental report for 2022, 83% of total GHG emissions are CO₂ that come from energy consumption. Meanwhile, 11% of total GHG emissions derive from fluorinated greenhouse gases (F-GHGs) used in TSMC’s manufacturing processes. GHGs in the form of CO₂ from energy generation can, at least in principle, be mitigated or even eliminated, for example, by switching from fossil fuel-based energy to renewables. Mitigating or eliminating F-GHGs in the manufacturing process is a whole other challenge. F-GHGs are used in various steps of manufacturing related to etching semiconductors. And, as yet, there are few or no substitutes for their uses in those processes. But, depending on the specific F-GHGs in question, they are hundreds to thousands of times more potent greenhouse gases than is CO₂. Fixating too much on carbon in the absence of distinctions like those suggested between CO₂ arising from energy use and the global heating impacts of F-GHGs is going to miss the different problems and solutions associated with those distinctions. F-GHGs may only be 11% of TSMC’s overall GHG emissions, but reducing or eliminating that 11% may actually be substantially more difficult or even impossible (because no substitutes for F-GHGs are on the horizon) compared to the CO₂ arising from the company’s energy use.

So carbon fixation even has an impact on thinking about problems and solutions associated with the climate emergency and the electronics manufacturing sector. But the effects of carbon fixation go further, risking drawing attention away from a variety of other environmental impacts from the sector. Let’s look at water consumption, for example.

Page 112 of the TSMC report shows data for total city water consumption at the company’s Taiwan-based facilities. Between 2018 and 2022 total city water consumption increased every year. In 2018 the company used 51,000,000 m³ of municipal water. This almost doubled by 2022 to 96,800,000 m³ (access to freshwater resources for semiconductor manufacturing is acutely impacted by the climate emergency, as I have written about elsewhere).

Just as TSMC’s consumption of water has been increasing, so to have wastewater discharges. Between 2018 and 2022 the company’s wastewater discharges rose from 33,700,000 m³ to 64,000,000 m³, again almost doubling. Later in the report on page 230, TSMC reports that in 2020 and 2021 more than 42 percent wastewater discharges from its facilities were “above effluent standards”. By 2022 that figure was over 54 percent. In other words, more than half of all water discharges are exceeding effluent standards (the report does not specify whether these standards are internal company standards or state mandated legal standards).

Like water consumption and wastewater discharges, both hazardous and non-hazardous waste generation by the company’s facilities show an upward trend between 2020 and 2022. In 2020 the company generated 575,740 metric tons of waste. By 2022 that figurehead increased to 744,019 metric tons, a nearly 30 percent increase. Meanwhile, over the same time hazardous waste generated increased from 288,400 metric tons to 401,215 metric tons, an increase of about 20 percent.

In presenting all these data TSMC includes both aggregate values as well as measures of per unit or per product intensity (e.g., water use per wafer manufactured). Per unit measures like this often show improvements in efficiency i.e., less use of resources or lower emissions per unit of wafer produced. The TSMC sustainability report does indeed show improvements on a per-unit basis on many of the measures described above. But it is really important to pay attention to the relation between per unit efficiency gains and aggregate results. For example, if a company like TSMC makes a 10% gain in efficiency of resource use per wafer produced, but then sells 10% more wafers than it did before making the efficiency improvements, the aggregate gain in efficiency is zero. This is the Jevons paradox or rebound effect, something I’ve written about elsewhere. It’s why the data in this TSMC report in many cases show aggregate increases in indicators like water consumption and wastewater discharge, even as the the company simultaneously makes improvements on a per unit of product basis.

I think what the concept of carbon fixation might help analysts, including myself, do is to think carefully about framing problems around pollution. Carbon fixation draws our attention to the work being done by formatting a pollution problem in one way, rather than another. The point isn’t that there’s one best way to format a problem. The point is that framing is inevitable and, consequently, it’s important to be as aware as one can be about both the possibilities and the limits of this or that framing. The electronics manufacturing sector is contributing to the climate emergency. The climate emergency is impacting electronics manufacturing. But there are other acute and chronic pollution problems associated with the sector that matter. An over emphasis on carbon dioxide risks bracketing these out of the analytical frame.

References

TSMC. 2022. “TSMC 2022 Sustainability Report.” https://esg.tsmc.com/download/file/2022_sustainabilityReport/english/e-all.pdf.