Traditional air conditioners and heat pumps use refrigerant gas to cool or heat homes and buildings, creating potential environmental hazards. A team of European scientists is trying to solve this problem using new experimental materials made from ceramics.
A recent study published in the journal Science describes a new type of "electrocooling" material, an air-conditioning technology designed to perform cooling (or heating) tasks without using dangerous or potentially polluting gases. Scientists at the Luxembourg Institute of Technology in Belvaux have developed a new ceramic-based prototype with a strong electrical cooling effect by combining several existing technologies.
When exposed to an electric field, electrothermal systems heat up because the electrically unbalanced atoms in the material are forced to line up in one direction like a comb. The entropy value decreases and the neatly arranged atoms begin to vibrate at an accelerated rate, causing the temperature to increase.
The new prototype uses fluids flowing between plates of ceramic-like material to carry away excess heat. If the electric field is turned off, the effect is reversed and the material becomes cooler than the ambient temperature, taking heat away from the fluid. Then, the cycle begins again.
Neil Mathur, a materials scientist at the University of Cambridge, said the electrically cooled prototype has shown "super performance". When used in refrigerators or air conditioners, the new material can dissipate heat to the outside of a building while keeping the interior environment cooler. A heat pump, on the other hand, cools the outside environment by extracting heat from the outside environment and bringing it indoors.
Existing air conditioning systems are highly efficient but require the use of refrigerants such as hydrofluorocarbons or ammonia, which directly or indirectly contribute to the greenhouse effect. The electrolysis prototype doesn't require the use of hazardous gases, and because it doesn't require a compressor, it can be made smaller and simpler.
Although prototypes of the technology have shown some remarkable capabilities, they are not yet ready for commercialization. Luxembourg scientists need to further refine the technology and increase the efficiency of the new material. Getting electric heat pumps to compete with those used in existing air conditioning systems is their current priority.