Air conditioning is threatening our ability to tackle climate change. Here's what we need to do 

As the latest round of global climate talks, COP24, came to a close in Katowice, in Poland’s coal country, much of our climate discourse has taken on a note of abject despair. The National Academy of Sciences tells us that current rates of warming, comparable only to the effects of a “meteorite impact”, will take us back to a climate that predates the evolution of modern humans. An article in Nature warns us of a “Nonlinear rise in Greenland runoff in response to post-industrial Arctic warming” (or, in non-geek-speak, that the melting of the world’s ice sheets has gone into overdrive).

The University of Washington draws parallels between our situation today and the “great dying”, the mass extinction event 252 million years ago that wiped out 96% of ocean life. The IPCC’s latest report warns of the most damaging effects from climate change - severe food shortages, wildfires, mass die-offs of coral reefs, climate-induced conflict - coming a lot sooner and at a lower temperature threshold than previously thought.

Meanwhile, there has been an increasing amount of attention paid to the massive climate risk posed by one mundane and increasingly ubiquitous household technology: the air conditioner. Researchers at Lawrence Berkeley National Laboratory, the International Energy Agency (IEA), and Rocky Mountain Institute (RMI) have concluded that room air conditioners alone - the typical window and split units used in most homes - are set to account for over 130 gigatons (GT) of CO2 emissions between now and 2050. That would account for 20-40% of the world’s remaining “carbon budget” (the most we can emit while still keeping global warming to less than 2˚C above pre-industrial levels - the goal set at the Paris Climate Conference in 2015).

Despair is understandable, but not very helpful. As RMI’s chief scientist, Amory Lovins, likes to point out: “Pervasive dread... is numbing and demotivating.” It is instead much better to act in the spirit of “applied hope… [with our] sleeves rolled up and fighting hard to change or beat the odds”.

Lovins’ latest insights suggest plenty of reasons to be hopeful; specifically, because the climate change mitigation potential of energy efficiency is actually several times larger and cheaper than previously thought. Lovins points out that “saved energy is already the world's largest source of energy services, bigger than oil” - that is, reductions in global energy intensity between 1990-2016 saved more energy in 2016 than all the oil burned that year.

Unlike renewable energy, whose cost has plunged in the past decade, energy efficiency had been assumed to cost more as the cheapest methods are exhausted. But this widespread assumption is based on economic theory (viewing efficiency as a dwindling resource), not engineering practice, which demonstrates that faster adoption and integrated solutions can rapidly drive down costs.

Buildings, which directly or indirectly account for nearly 40% of CO2 emissions, stand to gain the most from ‘integrative design’ - that is, designing energy-using systems not as isolated components but as a whole. These approaches make order-of-magnitude building efficiency improvements economically and financially viable - mainly by eliminating or shrinking heating, ventilation and air-conditioning (HVAC) equipment.

And for the air-conditioners (AC) we can’t eliminate, RMI research suggests that radical improvements are possible to tackle climate change. The compressor technology at the heart of most AC units has barely reached 14% of its theoretical maximum efficiency (with most AC units in the 6-8% range). Contrast this with solar panels (which reach 40% of their theoretical efficiency potential) or LED lighting (70%). There are credible pathways to a solution that is four or five times more efficient, both by hybridizing existing technologies, and in the form of new systems being developed in labs and research centres - such as transferring heat between semiconductors, employing magnetic fields, and even ejecting heat into outer space.

The challenge, of course, is helping these technologies find a way to scale. The AC industry is dominated by a handful of large incumbent manufacturers that are simply responding to current regulatory and market signals. Consumers care about price, brand and look more than anything else, and regulators fail to apply much pressure with regard to efficiency standards. Consequently, AC companies typically spend more on advertising and aesthetics than they do on research and development, and focus on churning out as many low-efficiency units as they can as cheaply as possible.

We can, however, change this dynamic. Regulators around the world can raise minimum energy performance standards closer to those of best-in-class ACs, which are typically twice as efficient as the market norm (an effort being driven by the Kigali Cooling Efficiency Program). Government procurement agencies and large private-sector buyers (like real estate developers) can leverage their buying power in the form of advance market commitments and bulk procurement programs for super-efficient ACs. In the interest of saving taxpayer dollars and delivering value to their customers, it makes perfect sense for governments and developers to procure the products with the lowest life-cycle costs. Simple financing solutions can encourage people to buy more efficient ACs. Forward thinking utilities, for example, can offer ‘on-bill’ financing, which allows consumers to pay for energy-efficient appliances on their electricity bills and in installments - effectively enabling them to realize cash savings from the very first day.

And critically, philanthropically-supported challenges can help raise the technology ceiling. The recently launched Global Cooling Prize could help promising start-ups and entrepreneurs find an audience, bypassing the traditional channels to market that are dominated by established manufacturers. It could also spur complacent incumbents into more ambitious action - succeeding where more incremental regulatory approaches have failed. In the month following its announcement, the Prize has attracted registrations from over 1,000 companies and individuals, representing over 20 countries - as encouraging a symbol of applied hope as we could have wanted.

António Guterres, the UN Secretary General, delivered a stark, simple message in Poland; “We’re running out of time. To waste this opportunity would compromise our last best chance to stop runaway climate change.” We know what constitutes that “last best chance” to tackle climate change; driving continued efficiency - already our largest energy resource - through exponential, whole-systems approaches. And focusing our innovation efforts on the technologies that have the greatest upside and the greatest impact on our planet’s future; starting with the devices we use to cool ourselves in a rapidly warming world.

For more, read the report Solving the Global Cooling Challenge, available here.