As the world’s leaders come together to discuss climate change, cold should be on the agenda.
It sounds counterintuitive, but cooling must be part of the debate around global warming. Cooling is currently part of the problem, and it’s getting worse, but it could become an important part of the solution.
Take one American city as an example of the environmental challenge of cold. Phoenix exists, in its current form, because of air conditioning. Air conditioning in homes, offices, buses and cars makes Phoenix, like many other desert cities, liveable. In the heat of the summer, cities around the world would be almost unbearable if it weren’t for artificial cooling.
And as the planet warms, the demand for air conditioning will grow. Estimates suggest that by 2060 the amount of energy used to cool buildings will surpass the amount used on heating. That is an enormous turnaround when it’s considered that human civilisation has depended on fire for thousands of years, but artificial cooling is a 20th century invention.
That cooling is having a significant impact on the environment. America uses more electricity to run its air conditioning than Africa uses on everything. Generating that electricity creates greenhouse gas emissions, which further warm the planet, causing more of us to install air conditioning and so on.
And in Phoenix we are seeing a more localised phenomenon, which replicates the global vicious cycle. Air conditioning creates cold indoors, but simultaneously it pumps out heat into the atmosphere. Studies have shown that the cumulative effect of all this cooling is a localised warming of the night air by about 1 degree.
That might not sound very much, but when you consider that Phoenix is only one of hundreds, if not thousands of cities that are fighting to stay cool. And when it’s recognised that air conditioning is only one of many applications of cooling, then the warming effects of cold start to become very serious.
The problem is also growing rapidly. The world is warming up, and at the same time large parts of the planet are becoming richer, and as a result of both these factors the global demand for cooling is growing extremely rapidly.
Take refrigerators for example. As people get richer, they buy a fridge. Over 95 per cent of urban households in China now have fridges, compared to only seven per cent 20 years ago. That is a process that is being replicated around the world. Adding millions of new fridges creates substantial additional demand on the energy system, but the effects are also more far reaching.
With domestic fridges becoming the norm, there is a need to provide consumers with food which isn’t just chilled at home, but has been kept cold from the farm to the fork. Newly affluent middle classes in Asia, Africa and South America expect exactly the same lifestyle as those of us in Europe or America, and that includes access to food that often travels large distances, but must still arrive in good condition.
As a result, refrigerated trucks are going to become as common a sight on the streets of Jakarta and Delhi as they are in London or Berlin. There are currently between two and four million refrigerated trucks on the world’s roads, but the figure is predicted to rise to over 15 million by 2025.
At present, those trucks almost always rely on polluting diesel engines to keep their cargo cool. Not only do they add to poor air quality, but in an attempt to keep feed cold, they are contributing to global warming.
I have long argued that cold sits at the nexus of global challenges of food, water and energy. Greater proliferation of refrigeration will help to reduce the amount of food that is wasted, it will help to feed growing populations and prevent the squandering of vast amounts of natural resources consumed in agriculture. It can have a positive impact around the world.
But unless we can move to clean cold technologies and systems, we will create catastrophic environmental consequences and the vicious cycle experienced in Pheonix will be replicated around the world.
The challenge shouldn’t be under estimated. To meet the demand for air conditioning that’s predicted by the end of the century we will require 2.6 million wind turbines, up from only 260,000 in operation around the world today. No matter how hard we try, it will be almost impossible to decarbonise cooling, just by decarbonising electricity. We have to change the way we generate cold, as well as the way we generate power.
The good news, however, is that new approaches, innovative technologies and resource efficient systems are out there and they are beginning to take hold. Only last month the University of Birmingham outlined its recommendations for how we can grasp the opportunity to ‘do cold smarter’.
Change is undoubtedly coming. But if we are to break the negative cycle of cooling leading warming, then cold must be on the agenda of global climate change talks and collective solutions identified.
We can transform cold from part of the problem, to part of the solution for a warming world.