[ad_1]
SINGAPORE: A newly developed “liquid window” can block sunlight to keep a building cool, but also absorb heat that is gradually released during the day or night to reduce energy costs, the scientists said.
The window, invented by researchers at Nanyang Technological University, Singapore (NTU), uses a hydrogel-based liquid between glass panes and was found to reduce energy consumption in buildings by up to 45% compared to the traditional glass windows.
It was also about 30 percent more energy efficient than commercially available energy-efficient glass, as well as cheaper, said NTU scientists who spent nearly a decade on the project.
“Previously, people only talked about blocking sunlight in the summer and letting in sunlight in the winter, but nobody was talking about heat storage, we are the first to do this,” said lead researcher Long Yi .
The “liquid window” material can be used for small or large glass pieces. “It’s like water,” Yi told the Thomson Reuters Foundation.
Energy-intensive buildings, many of which are heated by fossil fuels, account for 40% of global energy use, and windows are responsible for half of that energy use, according to a 2009 United Nations report. .
The smart window becomes opaque when exposed to heat, thus blocking sunlight and, when cold, it returns to its original “transparent” state. (Photo: Nanyang Technological University)
The International Energy Agency said direct and indirect emissions from electricity and commercial heat used in buildings that heat the planet rose to their highest level on record in 2019, accounting for 28% of related global CO2 emissions. with energy.
The increase was due in part to growing demand for energy for heating and cooling, with increased ownership of air conditioners and extreme weather, the agency noted in a 2020 report.
Conventional energy saving windows are made with expensive coatings that reduce infrared light entering or leaving a building, helping to reduce the demand for heating and cooling.
But they don’t regulate visible light, an important component of sunlight that causes buildings to heat up.
To overcome the limitations, the NTU researchers mixed microhydrogel, water, and a stabilizer together, and found that it can effectively reduce energy consumption in a variety of climates by automatically responding to changes in temperature.
The liquid mixture in the “smart window” becomes opaque or icy-looking when exposed to heat, blocking sunlight.
When temperatures cool, it returns to its original clear and transparent state, letting in light and heat.
The liquid mixture used to create the smart window is made of microhydrogel, water, and a stabilizer. (Photo: Nanyang Technological University)
NTU scientists conducted simulations using building models and meteorological data from Shanghai, Las Vegas, Riyadh, and Singapore, as well as outdoor tests in Singapore, Guangzhou, and Beijing.
They hope to start working with companies soon to spark commercial interest.
The windows, most suitable for office buildings that are occupied during the day, can be adapted for different locations.
But they are most effective in the tropics and places where temperatures rise during the day and drop sharply at night, such as the Middle East, Long said.
The tests also suggested that the smart liquid window reduces noise 15 percent more effectively than double-glazed windows.
