Fast forward to the end. The 17 UN Sustainable Development Goals have been delivered, the 169 sub-targets reached and the world has been truly transformed with no-one left behind.

It might sound farfetched. But for Toby Peters, Professor in Cold Economy at the University of Birmingham, it is worth keeping the ambition in mind. 

How can we deliver sustainable, clean and affordable cold chains?

“These goals have outlined what the world needs to look like. So, if we are going to achieve that, what will we actually need?” he asks. “More than just looking at current trends and a growth curve, we should be back-casting from that end goal. We might be guilty of having got too wrapped up in our projections and lost sight of the moon, as it were. We have set out the goals, we must work to meet them with no-one left behind. Not just move towards them.”

That perspective might not seem revolutionary in itself, but it represents a sea-change from many policies and roadmaps that lean on the traditional tendency to forecast using current trends.

For the future of cooling, getting a clear view of the target is crucial. According to the UNEP (United Nations Environment Programme) Technology and Economic Assessment Panel, energy demand for cooling is projected to nearly triple by 2050 based on GDP growth.

But as per Professor Peters’ philosophy of meeting the full suite of goals, to truly deliver 'cooling for all' within our environmental parameters we should look beyond such forecasts and work backwards. If we achieve that, demand could double again on top of that projection.

“The current growth in demand for cooling is not sustainable,” states Professor Peters. “Simply making the technology more efficient, and moving towards greener electricity, is not going to solve the problem. They are partial answers, but how do we truly deliver cooling for all within the climate change constraints? That is the real challenge.”

Making cooling ‘clean’

Cooling is an invisible industry that plays a crucial role in modern society. By removing heat from homes, offices, warehouses and trucks, cold chains allow us to safely deliver food and vaccines over long distances, air conditioners make our workplaces and homes comfortable, fridges keep our food safe and industry and commerce can keep huge units, such as data centres, operating 24/7.

For many markets, 50% of electricity consumption in the summer months is already used for cooling, while peak electricity in hot countries is driven by air conditioner usage. We are projected to see 19 new cooling appliances deployed every second up to 2050.

The demand for cooling is growing exponentially, and yet more than a billion people suffer the daily consequences of no access to cooling. Providing cooling for all will only increase the demand. A key component of a long-term cooling strategy will need to address one of the biggest drivers of demand – food.

“Currently, 30 to 40 per cent of food harvested in developing world is lost. Before it reaches the market,” says Professor Peters. “Cold chains would allow you to both reduce the high levels of loss and connect that food to new marketplaces, hundreds of kilometres from source. In doing so you can enhance economic wealth, cash flow and security for farmers, growers and fishers, and improve food quality, nutrition, safety and value to the consumer. This approach would also extend to improving access to essential vaccines. It is crucial to us achieving the Sustainable Development Goals. But to provide cooling wihtout over-heating the world only works if we truly embrace ‘clean cooling’.”

‘Clean cooling’ is about delivering cooling to all within our CO2, natural resource and clean air targets. To deliver all of the outlined goals, it must be accessible, financially sustainable and with the minimum possible environmental and natural resource impact. 

“The reason I have been so drawn to clean cooling is that it truly addresses all of the UN's development goals, there is no cherry picking,” states Professor Peters. The 2016 Report, Clean Cold and the Global Goals, from the Birmingham Energy Institute outlined precisely how it intertwines with all 17 goals.

“Knowing that the demand will rise so much alongside the need to think about ‘clean’ cold, we must fundamentally change our approach to cooling. That means we need to address the elephant in the room – energy.”

We need to talk about energy

Talking to Professor Peters, it becomes apparent that energy is the paramount obstacle. Or rather, how we talk about it.

The 2018 report, A Cool World: Defining the Energy Conundrum of Cooling For All, carried out a robust analysis of data, market, consumer and regulatory dynamics to calculate that, to meet the required targets of universal cooling, we would likely need a 70% reduction in primary energy usage. The most optimistic projections based on current efficiency pathways have us achieving, at most, half of this.

For Professor Peters, this means harnessing all the available energy resources including thermal, and changing our current approach to talking about energy systems and storage.

“When we talk about energy we inherently talk about electricity, and when we talk about energy storage we talk about batteries. We are defaulting to the historic norm, taking a fossil-fuel based system and maintaining it through our projections into 2050 and beyond,” he says. “We have to change the question itself and not look at how we generate electricity, but understand the services we actually need and the optimum way to deliver them from all resources available.”

He uses the idea of modernising a bus to explain how this works in practice. “We have tried to replace diesel engines with electric powertrains, but there is a lot more to consider. The air conditioning requirements for buses in the UK is a very different to that in sub-Saharan Africa. What you should actually do is bring in an electric powertrain for the motion, but look at thermal stores for the thermal load. If we want a thermal service, are we better off thinking thermally throughout the system as a whole. Should you store energy in a Lithium-ION battery?”

“That is, in essence, what we need to do on a global scale but locally,” he claims. “You have to look at the energy demand, understand the system, the available energy resources and then get the right energy stores to service those using a merit order of intervention.”

At the Birmingham Energy Institute the approach is two-fold. Firstly, to look at cooling on a system level. The work by Professor Peters and the team provides a framework for a new needs-driven, integrated system-level approach that helps to understand the size and location of the demand for thermal, waste and wrong-time energy resources. 

Only then can you look at the novel energy vectors, thermal stores, clean cooling technologies and new business models that can integrate those resources optimally with various cooling loads. Which leads us to the second focus, developing the new technologies themselves. In particular, in the crucial field of energy storage.

Novel solutions drive sustainable cooling

More than 80% of the global impact of refrigeration and air conditioning systems is associated with the indirect emissions of electricity generation to drive the cooling appliances. For all of the time spent engineering more efficient appliances, only a fundamental overhaul of the way cooling is provided would move the dial sufficiently to allow for sustainable cooling for all. 

With a growth in intermittent renewables, the storage device between the generation and the demand becomes ever-more crucial. If the majority of our demand going forward is set to be for thermal energy, it would make sense to use thermal storage. 

Professor Yulong Ding, Director of the Birmingham Centre for Energy Storage, has been at the forefront of thermal energy storage research for over a decade, since with Professor Peters he invented the current concept for Liquid Air Energy Storage (LAES).

In 2018, the world’s first operational grid-scale LAES plant opened in the North-West of the UK. The plant works by soaking up excess wind and solar energy, compressing and cooling air to -196°C, transforming the air to a liquid state that can be stored. When the stored energy is required, it is pumped to a high pressure and heated by ambient heat, creating a high pressured gas that is used to rotate a turbine, which generates electricity.

Listen to Professor Yulong Ding talking to BBC Radio 4 about the future of liquid air energy storage.

His work hit the headlines again in early 2019. Working alongside CRRC Shijiazhuang, a leading Chinese railway rolling stock company, the Birmingham team developed the world’s first shipping container using phase change materials (PCM).

The “refrigerated” truck-to-train container is more efficient than conventional equipment, providing a more stable temperature and, as a consequence, a higher quality of goods at the destination. The technology has recently completed commercial trials carrying real goods for 35,000km of road and 1000km of rail transport across different climate zones.

Once charged, the phase change material (PCM) inside the container can keep the inside temperature between 5-12°C for up to 120 hours. Crucially, it does not need a power supply during its journey; an example of a technological solution that works within the framework of Cooling for All – a key component of a clean cold chain that connects people without putting an undue strain on resources.

70% of food is chilled or frozen at some stage between farm and consumer in developed economies. For food security and the associated Sustainable Development Goals it requires an integrated, seamless and resilient network of refrigerated and temperature-controlled pack houses, cold storage, distribution hubs and vehicles used to maintain the quality and quantity of food produce, while moving it swiftly from point of harvest to consumption point.

Professor Peters points to this work as an example of applying technological solutions that work within the Cooling for All world that they are working towards.

“There are so many options out there,” he adds. “We could look at sky cooling, a method by which we radiate heat into the sky. We could look at the rivers in our cities as heat-sinks for cooling as they already do in Paris. These solutions may not move the dial as far as we need on their own, but a multi-faceted approach will be needed.”

It is promising, though, that we are able to discuss clean cooling in terms of solutions. It is a far cry from a decade ago, when the first challenge to overcome was even getting people to acknowledge the pressing need for a fresh approach.

Dawn of the Cold Rush?

It has been quite the journey for Professor Peters, and the community of those passionate about the necessity for a revision of how we think about cooling.

“Even in early 2018 it was a glaring omission from the global conversation about sustainable development with just a few of us banging the drum,” he says. “Fortunately, we have now seen the early shoots of a step change, cooling is coming in from the cold.”

The World Bank hosted the International Conference on Sustainable Cooling in November 2018. The International Energy Agency, UNEP and many others have renewed their focus to include cooling. 

In India, the Global Cooling Prize was launched to challenge people to develop a climate-friendly residential cooling solution that can provide access to cooling without warming the planet. It runs alongside a national Cooling Action Plan. 

“We are starting to move on from the questions about why it is required,” says Professor Peters. He argues that people have woken up to the problem, and shifted their focus towards how we deliver a strategy that allows us to address it.

The next looming challenge might sit in the corridors of power across the world. Indeed, which government is prepared to pay today for solutions for a problem 40 years down the line? In a world of re-election cycles, how do proponents of clean cooling encourage policy makers to make change happen.

“There is a certain amount of industry inertia. If they make a product that is slightly more efficient they can sell it. The incremental performance gains are sufficient for them. Consumers, retailers, but particularly government, need to challenge them to do far more,” says Professor Peters.

“I suppose there are two main reasons. First and foremost, there is a huge commercial opportunity here. It is too great, and too obvious, for there not to be something of a Cold Rush in the next decade as industry and governments clamour for their share of an emerging market worth billions of dollars.”

The UK, for example, is a world leader in clean cold research and developing innovative technological solutions. The export opportunity for both knowledge and products is massive.

“There is a secondary driver though. With three billion people expected to join the global ‘middle class’ by 2030, you will suddenly have a shift in cooling demand and cold chains. You might find that the established chains are under threat and governments have to think very carefully about long term food security.”

“Planning now makes absolute sense. It prevents us going down dead-ends and investing in infrastructure that will not be fit for purpose in years to come,” he says. “If we are to create the world envisaged by the UN, our systems need to be designed with it in mind. And clean cold needs to be central to that.”


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