If I tell you "coconut" and "lemon", can you think of a fresh summer drink or ingredients for a nice evening of fusion cuisine? For a group of researchers at the KTH Royal Institute of Technology in Stockholm, neither of these things comes to mind. Rather, for them coconut and lemon are the basis for an innovative sustainable and energy-efficient building material. How does it work? Let's see together.
Coconut and lemon wood: the genesis of an innovation
At the heart of this discovery (detailed in a study that I link to you here) there is the creation of a sort of "thermal battery" that combines the insulating properties of wood with lemon peel extracts and coconut oil.
During the day, the wooden structure of this material becomes transparent, allowing solar heat to be stored and keeping internal environments cool, as well as promoting natural lighting. At night, however, it releases the accumulated heat and becomes opaque, thus contributing to energy savings (and offering privacy).
The magic happens thanks to the subtraction of lignin from the wood, to create open "pores" on its surface. These pores are then filled with extracts of citrus peel and coconut oil, which allow the material to store or release energy as needed.
An innovation that has its own style
The strength of this material lies in its chemical simplicity. Coconut molecules, through the transition from solid to liquid and vice versa, are able to absorb or release energy, similar to the process of melting and freezing water. This allows you to regulate the temperature of the rooms in a natural and efficient way.
If the temperature exceeds 24 degrees, the material cools. If it falls below that threshold, the material heats up. The research team estimated that 100 kilograms (220 pounds) of material can save 2,5 kilowatt hours per day in heating and/or cooling.
Wood, coconut and lemon: follow me for other energy recipes
If you see so much ingenuity around, it's because the urgency of finding sustainable solutions in the construction sector is evident. According to the International Energy Agency, construction operations represent 30% of global energy consumption and 26% of global energy sector emissions. In this context, the material developed by KTH researchers could play a crucial role in reducing the environmental impact of construction (although I would give a little thought also on hemp).
Although only limited-sized structures have been created with this material so far, researchers are optimistic about its large-scale applicability. By laminating thin layers together, large, thick panels can be prepared for scalable applications. This paves the way for a future where our homes and buildings could not only be more sustainable and low-impact, but also actively contribute to controlling the indoor climate in a natural way.
In short (Italian only)
The innovative approach taken by Swedish researchers, combining simple, natural materials such as coconut and lemon with modern technology, represents an excellent example of how science can contribute to a greener future.
It's not just a question of saving energy or reducing emissions, but of completely reimagining the way we build our world.
