National University of Singapore researchers have created an air conditioner system that doesn’t use chemical coolants or a compressor.
Although air conditioning hasn’t changed much ever since it was invented, Singapore researchers recently revealed a new technology that should make cooling more environmentally friendly and energy efficient. NUS (National University of Singapore) scientists unveiled a prototype development of an air conditioner that utilizes water rather than refrigerants. This prototype not only needs 40% less electricity to run but can also cool an area down to 18 degrees Celsius.
According to an associate professor in the Department of Mechanical Engineering, Ernest Chua, air conditioner units nowadays are based on a century-old design yet there haven’t been breakthroughs in how to make air conditioning easier on both the environment and energy use.
Although manufacturers of air conditioners have tried to improve their product’s performance by changing evaporators and compressors, Chua says that these only make marginal differences. He added that this issue needs a “quantum leap” to do real good. After four years of intensive research, Chua’s team created two new bits of technology that will allow air conditioners to use water instead of chemical coolants.
The first new technology is called a membrane dehumidifier. This device works by using special materials that absord water as well as a change in air pressure to pull water from the air as it goes through the membrane. According to Chua, the water that is removed is almost like drinking water and completely potable.
The second new technology, called a counter-flow dew-point evaporative cooler, then receives the drier air. The evaporative cooling removes heat, similarly to the way the human body’s process works in perspiring.
With these technologies, air conditioners no longer require chemical coolants or energy-depleting processes in order to work. These chemical refrigerants include CFCs (chlorofluorocarbons), and HCFCs (hydrochlorofluorocarbons). CFCs are harmful to the ozone layer and in 1987 were banned by the Montreal Protocol, while any country of the Montreal Protocol are legally bound by the Kigali Amendment to act against HCFCs.
These new air conditioners don’t need those toxins, however. In fact, according to Chua, a single liter of water, even collected rain water, can cool an entire master bedroom for anywhere between 15 and 20 hours. In addition, where regular air conditioners give out a byproduct of hot air, this prototype instead expels humid air, which is thought to still be cooler. Chua says this is done to avoid disturbances to the outside urban microclimate.
Chua added that although the prototypes may be able to protect against certain environment hazards, the 1.6 meter prototype isn’t the final version. He said he and his team plan to, over the next three to five years, find a way to make the air conditioning unit compact and more viable commercially.
Chua also said that their air conditioners can’t get any greener as there’s nothing greener than water. He then joked that if someone could find something better, they should let him know.
