I am writing this blog post from a branch of Greggs, the British bakery chain. There are no hipster bloggers working from its two little plastic tables and I’ve never been in this branch before myself. But I shall tell you why I’m here – I’m sat under a big air conditioning unit, and in front of me is a big open-fronted chiller. I am surrounded by the buzz of refrigeration, and pleasantly cool on a hot day. It’s a perfect spot to contemplate the role of cooling technologies in a warming world.
There are an estimated 1.4 billion fridges and freezers in the world today, 1.6 billion air conditioning units, and countless refrigerated lorries, warehouses, containers, medical appliances and other devices that require cooling. Taken together, they represent a major problem for the climate.
The biggest issue is not the energy use, though of course that matters too. The big problem with refrigeration is the coolants used.
All refrigeration works on more or less the same principles. A coolant is pumped through a coiled system that harvests heat inside the fridge and moves it to the outside, by alternating between gas and liquid states. Here’s a friendly Youtube explainer for the non-technical:
There are variety of different coolants that could be used, and in the old days, CFCs or HCFCs were used. When scientists warned that this family of chemical compounds was depleting the ozone layer, they were successfully banned under the Montreal Protocol and phased out. Manufacturers switched to the related HFCs, hydrofluorocarbons, and used them instead.
HFCs do not damage the ozone layer. Unfortunately, they do damage the climate. Seriously. As a greenhouse gas they are between 1,000 to 9,000 times more powerful than carbon dioxide. A small HFC leak has big consequences, and cooling technologies can and do escape. HFCs leak into the atmosphere during production and servicing, and most importantly, when they are disposed of at the end of their working lives.
The good news is that robust action is being taken on HFCs – more on that later this week. The bad news is that all those millions of fridges, including mine at home and the chillers opposite me, contain climate-changing chemicals. Millions more fridges and air conditioning units are rolling off production lines every day. What happens to all these machines when they are retired will make a critical difference to the liveability of the planet.
A fridge has to be disposed of carefully. It should be dismantled, and the coolant captured and stored. It can be reused, but there are also processes for HFC destruction that render them benign, which is obviously better. But these are technical processes that don’t come cheap. It’s much easier to dump a fridge or crush it, or to use the traditional Luton method, which is to drag your old fridge out onto the pavement in the night and leave it outside your neighbours house, where it will remain for six months before somebody finally calls the council.
In Britain, there are laws for the disposal of fridges. (That’s why the scrap metal guys ignore the fridges on the pavement, but a washing machine will be gone in 24 hours.) Many other countries don’t have these laws, and if people have to pay for fridges to be processed properly, they may be tempted to dump them. There’s no easy answer for proper recycling.
Reducing the climate risk from refrigeration will mean correct disposal of old fridges and air conditioning units. It will mean phasing out HFCs, reducing the use of refrigerants where possible, and finding alternative ways to stay cool in a warming world.