By Irina Slav
Now that it has become abundantly clear energy storage is the most important factor that can ensure the long-term success of renewable energy, the field has been brimming with potential breakthroughs. But while the majority of these seem to focus on improving existing batteries or finding alternatives to them, some scientists have taken a different path: heat storage.
A team of chemistry scholars from the Chalmers University of Technology on Sweden have been working on a project for the development of a so-called molecular solar thermal system since 2013, and now they have news to report.
The project, led by chemistry professor Kasper Moth-Poulsen, involved the design of a molecule—carbon, hydrogen, and nitrogen—which can capture solar energy and store it for as long as necessary until a catalyst causes a chemical reaction that results in the release of the energy in the form of heat.
According to the team, as quoted by Bloomberg Businessweek’s Adam Popescu, the molecule can store the energy for decades, which suggests it could outperform existing battery storage systems on durability: the average lithium ion battery lasts between five and 10 years.
But that’s not all. The researchers also say their system is much lower on the carbon footprint scale.
How does it work? The molecule captures the energy emitted from sun rays upon contact. It is then stored in a cold liquid until needed. When needed, the liquid with the energy storage molecules are introduced to a catalyst. The liquid warms and the energy is released as heat.
Yet it is not just liquid that the molecule can be stored in. In fact, Moth-Poulsen’s team has developed a laminate coating with the molecules that can be applied to a variety of surfaces, from clothing to windows and used to store and, when needed, release heat. While not the same as existing energy storage that stores electricity, heat storage could cut the electricity consumption of a household and, consequently, its carbon footprint, which seems to have become goal number-one for the human civilization.
The heat-trapping molecule is certainly an invention worth praising. Now, its commercial potential needs to be tapped. For this, Moth-Poulsen’s team needs investors. To attract them, the professor is coating a whole building on the campus of Chalmers University to showcase the abovementioned potential.
And there could be more. While the team has focused on heat storage in the molecules, the question of whether it can also release energy in the form of electricity will sooner or later get an answer, too. Even if it turns out it doesn’t, heat storage in a film-thin coating that can be put anywhere in a house certainly sounds good.
The reports of the breakthrough don’t include details about the energy density of the laminate coating, but Professor Moth-Poulsen says, according to Bloomberg, that it would at this stage be best for heating purposes in relatively small spaces. This is definitely a good start: a relatively simple storage system lacking costly components and materials is likely to be more affordable than batteries.
Now, it’s in the hands of venture capital investors to supply the funding needed to bring the molecular solar thermal solar system to market. But can this system replace batteries? Only when it starts producing electricity.