The Hunt for New Materials That Can Store Heat Energy.
A team of researchers working in an energy laboratory within the University of Tokyo has discovered a type of material that has the ability to store and preserve heat for long periods of time. The researchers named their discovery “heat storage ceramic”, an obvious tribute to the ceramic-like features of the material. The researchers published their findings in the scientific journal Nature Communications.
The team found out that the ceramic material can efficiently conserve accumulated thermal energy or heat for longer periods of time. This discovery could be very helpful for the renewable energy industry if the material’s heat-storage capability can be developed for energy applications. According to the researchers, the material also has the potential of being used in switching memory device and sensor applications.
The material uncovered by the group of researchers led by Professor Shin-ichi Ohkoshi is called stripe-type lambda-trititanium pentoxide. It is composed of oxygen atoms and titanium atoms. Because of this composition, it has the ability to absorb and preserve large amounts of heat energy. However, the most important characteristic of the heat-storing ceramic is that it can release the heat energy it contains when subjected to external stimulation. What this means is that the material’s heat can be controlled. A person can tap into the heat whenever he or she wants by applying pressure. This is the characteristic that attracted the attention of scientists and researchers looking for alternative sources of renewable power.
The heat-storing ceramic is a form of what is called a phase transition material. In simple terms, it’s a material that can accumulate latent heat energy in a wide temperature range and release the stored energy when subjected to pressure. For illustration purposes, the heat energy stored by the ceramic is about 70% of the heat energy present when water is at its boiling point. This energy can be released or transferred to another material by inducing a series of phase transitions. These phases may involve pressure-and-heat, pressure-and-current, and pressure-and-light transitions.
There are three methods on how to apply and store heat into the stripe-type lambda-trititanium pentoxide. One, directly apply heat to the ceramic. Two, run electric currents across the material. And three, irradiate the material with very strong light. The researchers are developing a system that might allow the material to be subjected to all three heat sources, possibly all at the same time. As to applications, the heat-storing ceramic can be most efficiently used in solar heat conversion systems. It can also be used to harvest energy from heat produced by industrial wastes. In other words, heat from plants and facilities can be recycled by storing them in the ceramics.
Furthermore, the heat-storing ceramic is environmentally friendly. This is because it’s composed of elements that are safe and abundant namely oxygen and titanium. Aside from being utilized in solar energy applications, researchers are also looking for ways on how to use the ceramics in other fields like air-conditioning, heating models, and other electrical applications. For example, the ceramic can be used for pressure-sensitive sheets, conductivity sensors, heating pads, and optical memory devices.
Gordon's expertise in the area of industrial energy efficiency and alternative energy. He is an experienced electrical engineer with a Masters degree in Alternative Energy technology. He is the co-founder of several renewable energy media sites including Solar Thermal Magazine.