MIT's zero-electricity cooling system could tackle the hottest regions of the world

Claiming 3rd place, we look at how a zero-electricity cooling system could meet the world's growing AC needs.
Sade Agard
A zero-electricity cooling system
A zero-electricity cooling system

Ibrahim Can/Interesting Engineering 

The fact that as the Earth warms, the technology needed by humans to stay cool will only make the environment hotter is one of the great ironies of climate change. 

The number of energy-intensive air conditioning systems is projected to quadruple to 14 billion by 2050, putting a strain on existing power grids. Better yet, the increase in cooling alone will account for a 0.5-degree Celsius rise in global temperatures, according to the World Economic Forum. 

Here's where a novel device unveiled by MIT researchers in October comes in. The cooling system appears to have been developed primarily to ensure an accessible and environmentally friendly cooling system solution. Remarkably, it requires zero electricity.

300% better cooling power

In a recent catch-up, the device's lead researcher, Dr. Zhengmao Lu, explained to IE, "We also showed a 300 percent cooling power enhancement over the state-of-the-art radiative cooler under unfavorable climate conditions." 

This is number 3 in Interesting Engineering's series, showcasing the best innovations of 2022. Check back to discover more about groundbreaking AI, unique solar panels, new 3D printing methods, and much more. 

The device resembles a regular solar panel, which, instead of providing electricity, would provide cooling. Picture the top of a food storage container, which, rather than producing power, provides cooling for the food. 

Technologically speaking, though, the cooling system has an architecture that combines radiative cooling, evaporative cooling, and thermal insulation.

MIT's zero-electricity cooling system could tackle the hottest regions of the world
The novel device on the left shows superior cooling power

Lu explained that it "reached lower temperatures than traditional evaporative cooling while using much less water." 

And talking about water...The device only needs a relatively tiny amount of it for maintenance so it can carry out evaporation. This would only need to be added once a month in wetter locations and once every four days in the hottest, driest regions.

"Our research has significant implications for energy-efficient cooling of buildings and perishable goods, particularly in areas with hot and humid climates," Lu said. 

An affordable game-changer

"Our research aims to address previous critical challenges in passive cooling, a potential game changer for addressing the world's growing cooling needs," he explained. 

This makes sense, considering that billions of people will soon be buying their first air conditioner (AC) in countries with fast-growing economies. These include countries such as India and Brazil, where already dangerous heat and humidity levels exist. 

Whether they'll be taking up environmentally-friendlier units will be a question of whether affordable solutions exist. That is, compared to the pollution-heavy models that have long dominated the market since the 1900s. 

And that's not all. Of the estimated 2.8 billion people living in the hottest parts of the world, only around eight percent currently have access to air conditioners (ACs). Now, compare this number to the lofty 90 percent in the US and Japan. If you were looking for an example of climate inequality among some of Earth's most vulnerable members, here's one.