Choosing the right refrigerant


15 April 2021
Experts agree that indirect emissions from electrical consumption are a more significant contributor to climate change over the equipment’s lifetime than refrigerant leaks Experts agree that indirect emissions from electrical consumption are a more significant contributor to climate change over the equipment’s lifetime than refrigerant leaks


A-Gas managing director John Ormerod discusses the refrigerants emerging as the key players in creating a low carbon future for comfort cooling and heating.

Change is happening rapidly in refrigerants as we look to reduce our carbon emissions and create a better world to live in. Low global warming potential (GWP), energy efficient refrigerants with low installation and maintenance costs are in demand as we put together the building blocks for a low carbon future. 

This is happening at a time when the pandemic has left a significant mark on the cooling industry. The medical and supermarket sectors are working flat-out as they look to meet the demands of a society facing up to the effects of Covid-19. Service and maintenance visits are increasingly important as cooling and heating systems work overtime to cope with the fall-out from this horrible virus.

Heating in the home

At work and in the home, human comfort is growing in importance as we also look to reduce our carbon footprint. New builds and retrofits are becoming more energy efficient as building regulations tighten, and we collectively get better at keeping the heat in and the cold out. 

By reducing heat loss and removing draughts, we generate a demand for more efficient heating, ventilation, and air conditioning systems. The Government has made no secret that it wants to create a society with a much-improved carbon footprint. Gas boiler installations will be outlawed in new homes from 2025 as they also target the installation of 600,000 heat pumps a year by 2028. 

More than 80% of homes are heated by natural gas or other fossil fuels, which are huge emitters of carbon dioxide, accounting for around 14% of greenhouse gas emissions in the UK. There will be a revolutionary shift away from natural gas boilers to heat pumps in new builds and retrofits, so heating will impact human comfort more than anything else. 

Tackling emissions in this area is a priority and one where we can make the most significant difference. The Government has highlighted heat pumps as a key tool in building a low carbon future. If the energy supplying our heating demand is produced from a renewable source, we are well on target to deliver carbon neutral heating.

The energy efficiency benefits of heat pumps are impressive. The amount of energy needed to run them is dwarfed by the amount of energy they produce – a ratio of around four to one – and that makes them a good choice.

Heat pump refrigerants

Refrigerant wise we are witnessing two routes to heat pump development. Some manufacturers are sticking with HFC refrigerants like R32 and R410A, while others, where it is possible, are opting for natural refrigerants like hydrocarbons when using monobloc systems that are situated outside of a building.

The refrigerant mainly used is the mildly-flammable A2L R32. It’s GWP is about a third of R410A, which is a considerable drop. It’s a more efficient refrigerant which means there is a lot less needed within a system, so its reduction of tonnes of CO2 equivalent is amplified. The possible gain in efficiency and reduced environmental impact makes R32 an attractive proposition for domestic air conditioning installations and systems used solely for heating. 

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Air conditioning

Domestic air conditioning has struggled to catch on in the UK, but we could begin to see something new happening here as more people work from home. The big challenge comes from retrofitting our homes and workplaces. The Government will need to be bold here and introduce more incentives to encourage homeowners to move to low carbon heating. A heat pump is still expensive to install compared with a gas boiler. Still, Brexit may now provide the Government with greater flexibility to take charge of its own direction and have more choice for further financial incentives to make the switch.

Cooling wise, the lockdown has seen a rise in domestic air conditioning across Europe and the UK has been no exception. With more of us working from home, we are now taking a close look at how we can cool our homes more efficiently.

In smaller split systems, there’s been a noticeable move towards R32, but in offices, hotels and where larger VRF systems are preferred, R410A still holds sway. I am pleased to report growing interest in some of the lower GWP refrigerants emerging on the market as the F-Gas Regulation quotas begin to bite. 

Developing HFO refrigerants

Manufacturers have accelerated their ranges of low GWP equipment, and in tandem, significant achievements have been made with Honeywell’s Solstice® ze (R1234ze) and Solstice® zd (R1233zd), both with GWP around one, now finding favour in chiller systems. 

In replacing the incumbent R134a (GWP 1430), almost every equipment manufacturer has a full range of R1234ze offerings with their higher system efficiency. This helps meet the performance requirements of the EcoDesign and Energy Performance of Building Directives (EPBD).

Choosing a suitable refrigerant to help reduce global warming should, on the face of it, be a straightforward decision. In theory, all you have to do is replace a high GWP refrigerant with a low GWP alternative. In turn, CO2 emissions will be reduced, and you’ve ticked that box under the F-Gas Regulation step-downs. If only it were that simple.

Focusing on capital and operational costs

Energy efficiency is a critical factor when selecting a refrigerant kinder to the planet. You can view CO2 emissions as two distinct areas – direct and indirect emissions. The former relates to global warming potential, and the latter refers to system performance and energy efficiency.

Experts agree that indirect emissions from electrical consumption are a more significant contributor to climate change over the equipment’s lifetime than refrigerant leaks. That’s why it is always important to weigh-up system performance and energy efficiency before deciding on a refrigerant. 

There is an easy trap to fall into. Lifecycle costs, also known as an operational expenditure (OPEX), may not be at the forefront of your mind when designing a system. Capital expenditure costs (CAPEX), covering the cost of buying the equipment and start-up, can dominate. My advice is to do your homework on the lifetime and the start-up side; otherwise, any savings made at the beginning may be swamped by hefty running costs further down the road.

In the years ahead, I see a rise in the popularity of domestic air conditioning in the UK. Systems are getting more efficient, and with a growing range of low GWP refrigerants to match, homeowners can start to plan for a low carbon future in all seriousness.