As global temperatures continue to rise, finding innovative ways to keep buildings cool has become a top priority. Traditional cooling systems such as air conditioning are not only energy-intensive but also contribute to greenhouse gas emissions. Fortunately, advancements in technology have led to the development of new and exciting ways to keep buildings cool with minimal environmental impact.
Plant-Based Film that Keeps Buildings Cool
In a bid to provide an eco-friendly alternative, scientists have come up with a plant-based film that gets cooler when exposed to sunlight. The film comes in various textures and iridescent colors and has the potential to keep buildings, cars, and other structures cool without requiring external power.
This breakthrough material uses passive daytime radiative cooling (PDRC), which enables a surface to emit its heat into space without being absorbed by the atmosphere. Most paints and films currently in development can achieve PDRC, but they are white or have mirrored finishes. Colored pigments by nature cause extra warming of the surface due to the absorption of wavelengths.
The colorful plant-based film gets around this by not using any pigments at all. It uses cellulose nanocrystals derived from plants that can promote PDRC. Much like a bubble, the film uses different thicknesses to generate a color through a process called structural color.
The researchers made films with vibrant blue, green, and red colors that were nearly 40°F cooler than the surrounding air when exposed to sunlight. The material was also able to generate more than 120 watts of cooling power, which is comparable to residential air conditioners.
Going forward, the researchers plan to make the films more functional by using CNC materials as sensors to detect environmental pollutants or weather changes. With this innovative technology, buildings can be kept cool in an aesthetically pleasing and eco-friendly manner.
Harnessing the Cooling of Underground Water
A new study has found that using underground water to regulate temperatures could reduce the consumption of natural gas and electricity in buildings by up to 40% in the United States.
The technique, known as aquifer thermal energy storage (ATES), leverages the heat-absorbing property of water and the natural geological features of the planet to store thermal energy underground. ATES could help prevent blackouts during extreme weather events by providing a reliable and sustainable source of heating and cooling.
The study showed that ATES is a cost-effective and compelling option for heating and cooling energy storage that, alongside other technologies such as batteries, could help decarbonize the US energy system and enable a fully renewable grid.
New Method of Cooling: Ionocaloric Cooling
A new method of heating and cooling called ”ionocaloric cooling” has been developed by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). This technique takes advantage of how energy is stored or released when a material changes phase, such as from solid to liquid.
By using ions to drive solid-to-liquid phase changes, ionocaloric cooling aims to provide efficient heating and cooling, which accounts for more than half of the energy used in homes.
The researchers hope this new method will help phase out current refrigeration systems that use gasses with high global warming potential as refrigerants. Ionocaloric refrigeration replaces those gasses with solid and liquid components, which removes the potential for global warming.
The researchers believe that this new method could meet all the goals required to replace current refrigerants and reduce the production and consumption of hydrofluorocarbons (HFCs) that are powerful greenhouse gasses commonly found in refrigerators and air conditioning systems. The team is currently developing prototypes to assess the scalability of the technique in facilitating substantial cooling, enhancing the system’s capacity to withstand changes in temperature, and optimizing its efficiency.