Termite Mounds Inspire Breakthrough: Researchers Discover New Method to Reduce Energy Consumption in Buildings

Researchers have made a significant discovery in reducing energy consumption in buildings by studying the structure of termite mounds. Led by Dr. David Andreen from Lund University and Dr. Rupert Soar from Nottingham Trent University, the project suggests that the lattice-like network known as an “egress complex” found in termite mounds can be replicated to optimize the interior climate of buildings. 

The research team studied the Macroterms Michaelseni termite mounds in Namibia, which are among the largest biological structures globally, reaching heights of over 26 feet and housing over a million termites. 

The complex structure consists of a dense network of tunnels, ranging from 3mm to 5mm in width, connecting the wider chambers in the mound to the exterior. During the rainy season, the tunnels emerge on the north-facing surface, directly exposed to the sun, while they remain blocked outside of this season. 

The researchers observed that this network facilitates the evaporation of excess moisture while ensuring adequate ventilation through oscillating or pulse-like flows of wind. These oscillations appeared to promote moisture regulation and ventilation. 

To further investigate the climate control capabilities of these oscillations, the researchers conducted experiments. They simulated wind conditions on a 3D-printed replica of an egress complex and drove a CO2-air mixture through it at varying oscillation frequencies. The study revealed that airflow was highest at oscillation frequencies between 30Hz and 40Hz, moderate at frequencies between 10Hz and 20Hz, and lowest at frequencies between 50Hz and 120Hz. The researchers concluded that wind oscillations at specific frequencies create turbulence inside the mound, effectively carrying respiratory gases and excess moisture away from its core. 

Dr. Soar explained that maintaining a delicate balance of temperature and humidity inside buildings while allowing the movement of stale air outward and fresh air inward is challenging for most HVAC systems. However, the structured interface observed in termite mounds allows the exchange of respiratory gases based on concentration differences, ensuring the maintenance of desired conditions inside. 

The research team is confident that the properties observed in termite mounds can inform more energy-efficient building designs. They specifically highlight the potential for construction-scale 3D printing, influenced by their research, to create homes that remain cool and effectively regulate the flow of gases and moisture.