The environmental cost of keeping cool
Despite having been around for less than a century, refrigeration and air-conditioning are now widely seen as essential in a modern home. What tends to be overlooked, though, is the environmental ramifications of this technology. Refrigerants are generally absent from the media and product brochures and are very rarely mentioned by environment groups that are more focused on more tangible issues, such as land clearing and coal seam gas mining.
However, the stakes are high. In 2012, the refrigeration and air-conditioning sectors consumed an estimated 22 per cent of Australia’s electricity production, while other greenhouse emissions come down to the powerful global warming potential (GWP) of some refrigerants where released, measured against carbon dioxide with its GWP of 1. A further related issue is ozone depletion.
The Montreal Protocol & beyond
In the late 1970s, thinning of the Earth’s ozone layer was observed over Antarctica, in turn increasing UV radiation levels. Areas affected included New Zealand and southern Australia. The finger was pointed at a range of ozone-depleting chemicals including chlorofluorocarbon (CFC) synthetic refrigerants (GWP 4660-10,200.) In 1987, the world came together to sign the Montreal Protocol, under which these substances would be phased out. As a result of this action, ozone damage is now slowly mending.
With the prospect of CFCs being largely banned from developed countries by 1996, industry hunted for substitutes and came up with new synthetic hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). Fluorocarbon lobby groups were established, including the US-based Alliance for Responsible Atmospheric Policy and the European Partnership for Energy and the Environment. Both of these misleadingly named organisations manufactured and promoted the use of synthetic refrigerants.
Hydrocarbons … are ozone-safe and are more energy-efficient than their fluorocarbon relatives.
HCFCs (GWP 79-1980) were chosen as an interim solution because they had a significantly lower ozone-depleting potential than CFCs, but they are greenhouse-polluting. The most commonly used is R22 (GWP 1760.) Subject to a phase-out under the Montreal Protocol, all HCFC usage is scheduled to end in 2040, but developed countries have largely stopped using them.
Today, HFCs are the most widely used refrigerants in Australia and New Zealand despite their typically huge GWPs (4-12,400). Commonly used are R134a (GWP 1300) and R404a (GWP 3922). Despite global trends being pointed upwards, HFCs are being phased down as a climate change mitigation measure and are about to be incorporated into the Montreal Protocol. Australia’s schedule to reduce HFC use by 85 per cent between 2016 and 2036 is unimpressive compared to overseas benchmarks, and New Zealand is yet to offer any tangible figures.
Greenfreeze technology
In 1992, as the switch from CFCs to other fluorocarbons was underway, a German Greenpeace campaigner named Wolfgang Lohbeck hired scientists to research the use of propane and butane hydrocarbon refrigerants, teaming up with an East German appliance manufacturer named DKK Scharfenstein to create the Greenfreeze fridge.
By arranging tens of thousands of pre-orders with German consumers, Greenpeace was successful in not only launching Greenfreeze onto the market the following year but also saving DKK from bankruptcy. Europe’s largest fridge producers quickly gave up their resistance to hydrocarbons and jumped on the bandwagon. From there, hydrocarbons have spread across most of the world and in 2013 represented about 40 per cent of the world refrigerator market.
Natural refrigerants
Hydrocarbons, carbon dioxide and ammonia are today widely used in a range of settings and have several advantages. Hydrocarbons (GWP around 3-11) are ozone-safe and are more energy-efficient than their fluorocarbon relatives. While they have become fairly mainstream in Australia, they are yet to make the same inroads into New Zealand.
Carbon dioxide is non-toxic and non-flammable and can be recovered from industrial sources, so avoiding the polluting effect of releasing the gas into the atmosphere. It is increasingly being used by supermarkets. Ammonia (GWP 0) is corrosive, flammable and toxic, with a strong odour useful for leak detection. Being highly energy-efficient it’s widely used by the food industry and for cold storage. Ammonia-based equipment is far more expensive upfront but pays for itself over its lifetime.
Natural versus synthetic
Growing global pressure to slash greenhouse emissions is giving hydrocarbons an upper hand in the marketplace, but the refrigeration debate has stirred up some controversy regarding their flammability, largely from the fluorocarbon lobby and allied groups. Essentially, hydrocarbons are safe where safety precautions are being followed, and the very small number of incidents covered in the media result from sloppy behaviour, often compounded by a lack of necessary safety equipment. Where a system is retrofitted, labelling the new refrigerant is crucial.
Aware that both HFCs and HCFCs have a limited future, large fluorocarbon players such as Honeywell and DuPont have thrown themselves a synthetic chemical lifeboat in the form of hydrofluoroolefins (HFOs, GWP ranging from<1-6.) The efficiency of HFOs is roughly on a par with fluorocarbons.
The HFO R1234yf is seeing a steady increase in Automotive use, spurred by HFC restrictions in Europe. However, it is mildly flammable and in a fire will release the toxic gases hydrogen fluoride and carbonyl fluoride.
Fridges & air-conditioning
A few years ago, despite the energy-efficiency advantages, the only hydrocarbon fridges and freezers to be found in Australia and New Zealand were a few pricy European imports. Since then, hydrocarbons have made huge inroads and now account for more than half of the Australian market. In New Zealand, progress has been slower.
Equally important is the chemical used in blowing the foam. An increasing number of models use the environmentally sound hydrocarbon, cyclopentane. This compares very favourably with HFCs, and perfluorocarbons that have a whopping GWP of 7390-12,200. In both cases, the key is to ask questions.
If you are replacing the compressor of an existing fridge or regassing a home air-conditioning system, switch across to a hydrocarbon.
In vehicles
Inevitably, a portion of the refrigerant found in car air-conditioning systems is lost to the atmosphere every year, giving most of these units elephant-sized ecological footprints; as a rule of thumb, the release of one kilogram of fluorocarbon has the same greenhouse impact as two tonnes of carbon dioxide.
At present, no new vehicles being sold in Australia or New Zealand have a natural air-conditioning refrigerant.
The solution is to re-gas at a facility that uses hydrocarbons and, if cost is not a consideration, to swap the existing refrigerant (if a fluorocarbon) with a hydrocarbon. Aftermarket hydrocarbon use is permitted everywhere in Australia and New Zealand, except for Queensland where it is severely restricted. Leak holes must be identified and sealed at the same time as the refill, and regular servicing is a good idea.
In addition to being slightly more fuel-efficient, hydrocarbon recharging offers very good cooling performance. Its usage is growing and, according to the latest estimate, around 10–12 per cent of vehicles in Australia are running with hydrocarbon air-conditioners, with the figure in New Zealand substantially lower.
At present, no new vehicles being sold in Australia or New Zealand have a natural air-conditioning refrigerant.
Disposal dramas
In Australia and New Zealand, the law prohibits venting of refrigerant gas into the atmosphere. When you take your old fridge or freezer to the tip, you are typically charged a fee for gas recovery unless you have a degas certificate. Similar gas recovery rules apply to unwanted domestic air-conditioning units and for vehicle air-con systems. From here on, things become more complex and ambiguous.
Australian contractors are paid a financial incentive of AU$3 per kilo for returned gas, while in New Zealand no equivalent arrangement exists. Unfortunately, this is dwarfed by the disincentive of paying around AU$20 per item to have refrigerant collected by an accredited technician.
The 2013 Cold Hard Facts 2 report prepared for the Federal Government points out that, while 500 tonnes of refrigerant is collected annually, this leaves a shortfall of up to 1200 tonnes per year unaccounted for. Tim Edwards of the Australian Refrigeration Association challenges this figure, which he feels is far too low. Another commissioned report estimates refrigerant recovery rates of 80 per cent for air-conditioning equipment, compared to a small 35 per cent for fridges and freezers. Financial disincentives are combined with insufficient policing, with a focus instead on “education”.
Fridge insulation foam probably contains a greater quantity of high-GWP greenhouse gas than is found in the coolant system, and most is released into the atmosphere when a fridge or freezer is recycled in Australia or New Zealand. Although recovery is technically feasible, and is mandated in the EU, the necessary equipment is expensive and is yet to be introduced in this part of the world. In 2014, Australia commissioned a cost-benefit analysis and decided against product stewardship.
So how do you go about disposal? For a vehicle or air-conditioning equipment, pay to have it degassed. In Australia, accredited refrigeration technicians are identifiable through a green and blue tick symbol, whereas in New Zealand no equivalent logo exists.
In the case of refrigeration items, foam-related releases limit the quantity of collected gas to about half of the potential total. Without certainty that a hydrocarbon foam blowing gas was used, this suggests keeping the fridge in a corner of the garage, if feasible, until the severity of climate change leads to policy shifts on foam gas collection.
Otherwise, government collection schemes are operating in some areas. For parts of New South Wales, the government-run Fridge Buyback scheme allows some types of second fridges or upright freezers to be collected and for just the refrigerant to be collected, with a small incentive payment made in most cases. A similar program is being run in the ACT by the electricity provider ActewAGL, but no equivalent initiative exists in New Zealand.
Energy tips for home refrigeration are to buy a model that is no larger than needed, keep the fridge thermostat at 3–5°C, check fridge seals for possible replacement and allow space at the back for ventilation.
A less definite approach is to rely on the facility or business where the fridge or car is going to be disposed of. Ask them how much they charge for the degassing and be prepared to walk away if there is no cost or no clear answer is forthcoming.
Go energy-efficient
A further consideration for domestic refrigeration and cooling products is energy consumption. Both Australia and New Zealand have efficiency star ratings, with a maximum for fridges of 10 stars (Australia) and six stars (NZ), and a 10-star rating for air conditioners (Australia only.) In addition to reducing bills, energy-saving appliances cut greenhouse gas emissions. Generally, hydrocarbon models are more efficient.
Australia’s highest-rated fridges stop at an uninspiring 4.5 stars. In New Zealand, a list of Energy Star fridges is available, but with no cross-referencing to star ratings it’s difficult to pick out the most efficient. Energy tips for home refrigeration are to buy a model that is no larger than needed, keep the fridge thermostat at 3–5°C, check fridge seals for possible replacement and allow space at the back for ventilation.
To save energy, look at minimising usage, clean the filter regularly, shut windows and doors and set the thermostat for 19°C in winter and 26°C in summer.
Creating a better future
Following the outcome of the Montreal Protocol, positive change in the refrigerant industry was inevitable. What remains undetermined is the policy directions and the speed at which this change occurs.
New Zealand is accelerating the transition away from HFCs with a levy that was introduced in 2013. Australia introduced a similar levy with the carbon tax, under which some HFC prices more than tripled. However, a big step backwards was taken when it was repealed in 2014.
Especially where there is no price signal to motivate a faster shift to environmentally benign refrigerants, consumers can play an important role by demanding these from the industry — motivated in part by the energy savings.
Ed’s note: A global deal announced on October 15, 2016, to amend the Montreal Protocol will cap and reduce the use of HFCs by 90 per cent in a gradual process beginning in 2019.
