R744 refrigerant: what is it and what are its benefits?

Amid growing concerns over the impact that F-gases are having on our environment, natural refrigerants – such as R744 – are becoming more and more popular.

Here’s all you need to know about R744 refrigerant – from what it is to its history and, most importantly, what makes it so great.

What is R744 refrigerant?

R744 is a refrigerant grade of CO2 gas.

It’s a natural refrigerant that’s very efficient and has a low global warming potential (GWP) of just 1.

It’s also non-toxic and non-flammable, meaning it’s classified as a safety group A1 refrigerant. As such, it can be used safely in public locations like supermarkets.

These are just a few of the qualities that make R744 refrigerant attractive for a range of use cases. Which brings us onto…

What are some common applications of R744 refrigerant?

R744 is one of the most common refrigerant gases used in commercial and industrial refrigeration.

However, it’s only recently started to gain popularity as a heat pump refrigerant.

Here’s the lowdown.

R744 refrigeration

In the UK, the refrigeration industry switched from harmful F-gases to natural refrigerants around 12 years ago.

So, R744 is a tried and tested refrigerant in commercial and industrial refrigeration.

At Clade, it’s our go-to for our refrigeration systems, which grace supermarkets, office spaces, convenience stores and factories – including for high street names such as Aldi, Co-op, John Lewis, Marks & Spencer and Morrisons.

Why? Well, R744 refrigerant is non-corrosive, non-toxic and non-flammable. Plus, it has the lowest GWP of all the natural refrigerants.

It achieves all this while being extremely efficient, allowing our clients to reduce their carbon footprint without sacrificing performance.

R744 heat pumps

Unlike the refrigeration industry, the heat pump industry in the UK still relies heavily on synthetic refrigerants and F-gases.

However, in the face of tightening F-gas regulations and concerns about both climate change and toxic pollution, R744 heat pumps are finally starting to get the attention they deserve.

At Clade, we’ve been designing, manufacturing and installing R744 heat pumps for years.

In fact, our R744 heat pumps currently provide both space heating and domestic hot water to settings including libraries, swimming pools, office buildings and supermarkets. And the results are impressive.

As well as bringing with them significant environmental benefits, natural refrigerants like R744 actually perform better than synthetic refrigerants when it comes to heat pumps. For instance, they achieve higher coefficient of performance (COP) at low ambients and high flow temperatures.

What are the benefits of R744?

Now you know a bit about R744. But what exactly makes it one of the best refrigerant gases?

Here are the main benefits, especially when you compare R744 to synthetic refrigerants like HFOs and HFCs.

Pros

• Low GWP. R744 has an extremely low GWP of just 1 – meaning it won’t play a part in accelerating climate change.
• Zero ozone depletion potential (ODP). With zero ODP, R744 refrigerant won’t contribute to the depletion of the ozone layer.
• No PFAS. Unlike synthetic refrigerants, R744 won’t pollute groundwater with harmful ‘forever chemicals.’
• Highly efficient. R744 has no glide, which makes it more efficient than synthetic refrigerants at low ambients and high flow temperatures.
• Cost-effective. R744 isn’t subject to patents and is highly efficient, making it a cost-effective alternative to synthetic refrigerants.
• Future-proof. R744 won’t be subject to tightening F-gas regulations, making it a future-proof option.
• Pure refrigerant. As a pure refrigerant, levels can easily be topped up after refrigerant losses.
• Safe. R744 is non-flammable and non-toxic, meaning it’s classed as a safety group A1 refrigerant.
• Non-corrosive. R744 is non-corrosive to copper and brass.
• High temperatures. R744 heat pumps have proven themselves at over 100°C, making them well-suited to high-temperature requirements.

Cons

• High pressure. R744 systems operate at high pressure – we take care of this in our factory and it’s tested by Lloyds Register for peace of mind.
• Return temperature. R744 needs a lower-than-normal return temperature, so it’s important to follow special guidance in system design.
• Odourless. R744 can’t be detected by smell in the event of leaks.
• Conversion. Existing fluorinated refrigeration systems and heat pumps can’t be converted to R744 – instead, it’s only suitable for new systems.

The history of R744 refrigerant

R744 exists in the atmosphere at a concentration of 0.04% by volume. So, it’s been around for as long as we have!

But it wasn’t until the 19th century that it began to be used as a refrigerant – the first machine using R744 was built in 1881, by Carl Linde.

Later, compressors were developed, and R744 started to be used extensively… until after the First World War when synthetic gases were developed. At this point, the use of R744 as a refrigerant began to decline as more and more businesses turned to synthetic gases instead.

Years later, it became clear that these new refrigerants were depleting the ozone layer. HFC refrigerants were developed to replace them, which are still used today. However, it was quickly discovered that these also contribute to global warming.

With the pressure to decarbonise and F-gases tightening, the heating and cooling industry was forced to start the hunt for alternatives.

In the UK, the refrigeration sector made the switch back to natural refrigerants – including R744 – around 12 years ago, recognising the benefits that they can bring to both people and the planet.

Meanwhile, the heat pump industry has taken a little longer to turn away from synthetic refrigerants. But they’re slowly being embraced by more and more heat pump manufacturers, as the need to reduce carbon footprints becomes ever more pressing.

And what about the future?

Well, we believe that natural refrigerants like R744 and R290 will be central to the commercial heating and cooling industry for the foreseeable.

After all, they’re high-performing, cost-effective and good for the environment. Plus, they won’t be subject to ever-tightening regulations and legislation – making them arguably the safest way to prevent your equipment from becoming a stranded asset any time soon.

Talk to us about R744 refrigerant

Curious to learn more about R744 refrigerant and how it can help your business to decarbonise?

As a certified B Corps, at Clade, we’ve been designing, manufacturing and installing natural refrigerant heat pumps and refrigeration systems for many years. So, you’re in safe hands.

Get in touch with our team of experts to learn how we can help you with a bespoke refrigeration or heat pump system that suits your business’ needs perfectly.