Earth Diagnosed with Stage 4 Climate Change

In recent years, the parallels between climate change and a lethal disease like cancer have become increasingly evident. Our planet now has, what I like to call, Stage 4 Climate Change – a critical condition that demands urgent attention and decisive action if you want to avoid certain death.

Much like cancer, climate change is insidious. It started out almost imperceptibly, but has now escalated into a severe life-threatening condition that affects ecosystems, weather patterns, and the overall health of our planet. Had we noticed and accepted the issue much earlier, it would have been significantly easier to treat, but no, we stuck our heads in the sand.

Why? Perhaps because, also like cancer – where the chance of survival often depends on expensive treatment and socioeconomic factors – climate change comes with a large helping of inequality. Most of the historic CO2 emissions are the result of economic development in regions like Europe and North America, but the increasingly severe effects are most keenly felt in Africa, Asia and by the many Pacific island-nations literally struggling to keep their head above the water.

COP28 – what’s next?

The outcomes of last years’ COP28 underscore the urgency of addressing this global crisis. The final text indicates for the first time a collective acknowledgment of the severity of the issue, but completely lacks the concrete actions and commitments that are paramount to stave off the impending catastrophe.

We stand at a critical junction where decisions made today will determine the fate of future generations. Governments, industries, and individuals must unite to accelerate the adoption of renewable energies and innovation of climate-friendly technologies. Like in the treatment of cancer with new types of medication and procedures – the development of new climate-friendly technologies gives hope that we can yet “treat” this climate change and avoid the inevitable.

Natural refrigerants

One of the most promising avenues for climate change mitigation lies in the adoption of natural refrigerants. Traditional synthetic refrigerants (like HFCs), widely used in air conditioning and refrigeration systems, contribute significantly to greenhouse gas emissions – and newer refrigerants that are supposedly better for the climate, are instead turning out to be potent sources of PFAS, a.k.a. forever chemicals, in other words, very bad for the environment and our own health. Recent research has even classified some of them as possibly carcinogenic, which is of course ironic considering the topic at hand here.

Natural refrigerants, on the other hand, offer a sustainable alternative that can drastically reduce our carbon footprint. In 2016, the UN adopted the Kigali Amendment, which calls upon countries to phase down HFCs. They have calculated that, if the amendment is fully implemented, we can reduce global warming by 0.4°C (0.72°F). That may not sound like much, but considering that we are on track for a 3°C rise in temperature, and we are trying to reduce that to 1.5°, it’s a LOT.

Stage 4 Climate Change

It’s therefore time to come together, leveraging solutions like natural refrigerants to combat the disease that is climate change. The time for change is now, and natural refrigerants offer a tangible and impactful solution in our fight against this global cancer.


The secret source of PFAS

Makeup, non-stick kitchen equipment, waterproof clothing and even dental floss all contain PFAS. A fact that has garnered considerable public attention in the past few years, and rightly so.

This group of so-called forever chemicals can accumulate in nature and via the food chain end up in our bodies with detrimental effects. Research has shown that they damage our immune systems, cause increased risk of cancer, increased cholesterol levels and birth defects – among many other things.

The growing concern about PFAS has led to calls for the complete ban of these chemicals in consumer products.

However, one significant source of PFAS has gone largely unnoticed: the f-gas refrigerants used in AC, refrigeration systems and heat pumps. Modern day refrigerants called HFCs and HFOs are successors to CFCs (aka. Freon) – the ozone depleting substances banned in 1987. They contain fluorine atoms and when escaping into the atmosphere, they degrade into a compound called trifluoroacetic acid, or TFA for short. Some are converted completely into TFA, others only partly.

TFA is one of the more than 12,000 compounds included in the EU definition of PFAS. It is highly soluble in water – returning from the atmosphere to our aquatic environments with rainwater – and accumulates there over time. In a 2021 study, TFA was found in 89% of drinking water boreholes tested in Denmark and once there, it is very difficult to remove.

The solution
TFA is luckily a problem that we can actually solve. We do it by switching to natural refrigerants!

Natural refrigerants are naturally occurring compounds like ammonia, hydrocarbons and even CO2. The do not contain PFAS and are very energy-efficient refrigerants. In other words, we already possess the technology to fix this problem. We just need to implement it.

In 2020, the EU proposed a complete ban on the “most harmful chemicals in consumer products” – including PFAS – as part the updated REACH legislation. Last summer, however, British newspaper The Guardian revealed that, under heavy pressure from the chemical industry, the European Commission was making a hasty retreat. With leaked documents The Guardian showed that the most likely scenario was now a ban on only 10% of these harmful chemicals.

In my humble opinion, it is downright despicable that the EU is bowing to pressure from an industry that makes huge profits off the back of our environment and health. We need to become less beholden to industry interests, so we can work towards sustainable solutions that prioritise environmental stewardship and human well-being over money and profit.


Bad CO2 or Good CO2?

We all know that carbon dioxide (aka CO2) is bad, yes? That has been drilled into us for well over 20 years. CO2 is a greenhouse gas, and therefore CO2 emissions should be avoided at all costs, at least if we want life to continue without increasingly frequent droughts, floods, storms or [insert favourite natural disaster here].

This is probably why people tend to look at me funnily when I argue that CO2 can actually help save the planet from the disaster we are hurtling towards.

Enter CO2 as a refrigerant!

Say again? A what? Most people have never stopped to consider exactly how their beer (or favourite snack) stays cold in the fridge, or how limited-life-span veggies stay fresh on their trip halfway around the world. But, in order for these things to happen, we need refrigerants.

What is a refrigerant?

A refrigerant is a substance that evaporates when absorbing heat – and in the process cools down whatever it absorbs the heat from, like the food in a refrigerator. This evaporated gas can then be condensed back into its original form using a compressor and some electricity. And, voila, it is ready to absorb more heat. This cycle, called a vapour-compression cycle, is what drives most refrigeration and air-conditioning equipment.

All refrigerants used in such equipment have an impact on the climate. Therefore they have been given a so-called Global Warming Potential (GWP) value. The GWP indicates the magnitude of a refrigerant’s greenhouse gas effect, making it easier comparing the climate-effects of different types. CO2 — which is also called R744 when used as a refrigerant — has a GWP value of 1.

Why is CO2 not just bad?

Now we are arriving at the crux of the matter, because synthetic refrigerants (f-gases) have GWP values that, in many cases, are thousands of times higher. Two of the most popular f-gas refrigerants over the last 20 years around the world are called R410A and R32. R410A has a GWP of 2,100 and R32 has a GWP of 771. In other words, R410A’s effect on the climate is more than two thousand times bigger than CO2’s. So, just to hammer home the message… 1kg of R410A released into the atmosphere is 2,100 times as bad for the climate as 1kg of CO2!

So, in conclusion: CO2 refrigerant has a small effect on the atmosphere, and is contributing to climate change if it escapes the refrigeration equipment. BUT, when it comes to refrigerants the alternatives are thousands of times worse.

We need CO2 for cooling

Why is this important? Could we not just stop using cooling? No, I don’t think so. I’m pretty sure the world at large is not willing to give up its cold comforts, especially not with the climate getting hotter all the time. We also need to cool medicines like COVID-19 vaccines.

So, if we can’t live without cooling, we need to choose refrigerants (like CO2) with the smallest possible climate effect to avoid making the situation even worse.

In 2016, the Kigali Amendment to the Montreal Protocol was adopted. The Kigali Amendment is an international agreement that calls upon countries to phase down the use of f-gases called HFCs. The UN has calculated that if the amendment is fully implemented, we can save up to 0.4°C of global warming in the 21st century.

That may not sound like much. However, when we consider that we are currently on track for more than a 3°C increase in temperature, and we are trying to reduce that to 1.5°C, then suddenly a 0.4°C reduction is a big deal.

In other words, replacing the hugely impactful f-gas refrigerants with CO2 can actually help save us from the climate crisis, not make it worse.

So, as usual, life is not purely black and white. When it comes to the climate it is a nice muddy brown. CO2 is not just the bad guy mucking everything up. It could be a useful tool when used to phase out even worse gases while continuing to enjoy a cold beer or running the AC on a hot day.

NOTE on CO2 emissions!

This doesn’t mean that CO2 emissions from burning fossil fuels are suddenly unproblematic, most certainly not. It’s a matter of choosing the least bad option, and in the case of refrigeration, that means choosing CO2.