Researchers from NTU Singapore have announced the development of a liquid window panel that can block the sun, regulating solar transmission, and trapping thermal heat to be released through the day and night. The goal of the new liquid window panel is to help reduce energy consumption in buildings. Researchers developed the smart window using a hydrogel-based liquid within glass panels discovering that the design can reduce up to 45 percent of heating, ventilation, and air conditioning energy consumption in buildings.
The 45 percent savings on climate control energy consumption is compared to traditional glass windows. The liquid window panel is also 30 percent more energy-efficient than commercially available energy-efficient glass while being cheaper to manufacture. Windows are a key component in designing buildings but are also the least energy-efficient part of the design.
Heat easily transfers through glass, and Windows have a significant impact on a building’s heating and cooling costs. A report from the UN in 2009 showed that buildings account for 40 percent of the energy used globally, and windows are responsible for half of that energy consumption.
Conventional energy-saving windows are made using expensive coatings to cut down infrared light that passes into and out of the building, reducing demand for heating and cooling. They don’t regulate visible light, a major component of sunlight that causes buildings to heat.
The NTU researchers used water, which can absorb a high amount of heat before it gets hot, something known as high specific heat capacity. The team created a micro-hydrogel, water, and stabilizer mixture in their design. They discovered through experiments and simulations that the material can effectively reduce energy consumption in various climates. The hydrogel mixture turns opaque when exposed to heat, allowing it to block sunlight and, when cool, returns to the original clear state.