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Efficient air-conditioners or the sensation of a cooler breeze?

Published on: 21 Aug 2018

Columnists: Nils Borg, European Council for an Energy Efficient Economy

The conversations during the hot days and humid evenings this summer kept coming back to climate change. They just had to. Raging wild fires in Sweden, normally a Southern Europe thing, higher temperatures in the North than in the South, farmers crippled by a serious drought and vulnerable people at serious health risk... We should expect this, more and more frequently.

But our conversations with friends and relatives also dwelt on more down-to-earth matters such as everyday means to manage the heat.

While visiting a young relative in Germany who lives in a hot apartment under the roof with a small baby, we discussed air-conditioners. She doesn’t have one. We talked about noise and energy, and she said “but now there are really efficient ones with A triple plus rating”. She is definitely not an energy nerd like me, and like most other people in the real world, energy is not at all at the core of her everyday life. But I was really happy to see that she knew about the label, she understood it and that she cared.

“On the other hand”, she said. “I don’t know if it is worth it (purchasing air conditioning) just for a month or two during the summer”. It still costs a lot of money.

Coincidentally, we had just stayed with a friend who has worked extensively in Pakistan with energy efficient cooling fans. You know, the big propeller-like units that are mounted below the ceiling.

There are no compressors and no refrigerants involved and they simply move the air and it makes us feel cooler. These types of fans inherently use less energy than air-conditioners – if designed well, that is.  The amount of electric energy used by poorly designed fans in Pakistan and other hot countries is staggering.

A Pakistani household spends a third of its income on operating these fans. A poor household has on average three fans installed while wealthy households typically have more than 20 fans. With an average fan power of 98W and an inefficient fan drawing up to 140W, a lot of energy is consumed to operate these units many, many hours a day.

Thanks to a new labelling programme, concerted efforts to help manufacturers improve the design and government procurement policies, efficient fans of around 60W are now entering the Pakistani market on a massive scale. They are domestically produced and don’t require rocket science to become efficient.

So how is this relevant for us? First of all, well designed intervention programmes combined with labelling can really transform the market. The other, bigger and more difficult question is about technology choice. In Pakistan, a fan is the preferred option for cooling. The challenge is to make that efficient and make sure that fans remain the preferred technology.

In Europe, domestic air-conditioning is picking up since many can afford it. But do we want this to become the standard, even if the units are a triple plus rated? Would we be content with natural ventilation and efficient fans. And in return be rewarded with less energy use and more silent nights?

To me, this is a question of energy efficiency versus energy sufficiency. We want to look at quality of life and energy consumption as a whole, not just optimising individual products and components. Don’t get me wrong here. I am firm believer in stringent product standards and ambitious labelling requirements. But I would like my young relative who is not an energy expert to know not only about the air conditioner label but also about all the options to improve comfort and efficiency. Then she can make an informed choice about making the apartment feel cooler, or not.

PS: The 2019 summer Study 3–8 June will explore the question “Is Efficient Sufficient?”. The call for papers will be launched shortly. Come and participate in this discussion.

PPS: Another interesting development is represented by rapid advances in wearable and personal cooling technologies that can increase comfort while reducing/eliminating the need for air conditioning. See my colleague Jason Erwin’s EEDAL paper here.