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BIOMIMICRY
HOW BIOMIMICRY IS SHAPING ZERO ENERGY BUILDINGS
By Eamonn Ryan
When it comes to designing buildings that consume minimal energy, engineers and architects often look to cutting-edge technology, advanced HVAC systems and solar panels. technical
But according to Max Rohr, director of education at Caleffi North America, some of the most inspiring solutions come straight from nature.
In a recent ASHRAE Journal Podcast, Rohr shared his insights on zero energy buildings and the role of biomimicry – learning from natural processes and animals to create more energyefficient structures.“ Animals have evolved to thrive in their environments with minimal energy. If we study them, we can find strategies to reduce the energy footprint of buildings,” Rohr explained.
Biomimicry offers profound lessons for building designers. Rohr explains that animals have evolved to survive and thrive with minimal energy, and humans can learn from these strategies to reduce a building’ s energy footprint.
For example:
• Elephants’ ears as natural radiators: The large, vascularised ears of elephants dissipate heat passively. Designers can mimic this principle by creating surfaces that naturally regulate temperature, reducing reliance on mechanical cooling.
• Polar bear insulation: Polar bears maintain warmth in harsh climates with minimal energy expenditure due to their highly insulating fur. This translates directly to building envelopes – well-insulated walls, roofs and windows can drastically reduce heating and cooling loads.
Perhaps the most striking architectural example is the Eastgate Centre in Harare, Zimbabwe, inspired by termite mounds. Termites construct complex mounds that self-regulate temperature through passive ventilation. The Eastgate Centre uses this same principle: as the building warms, hot air rises through chimneys and exits, drawing in cooler air at lower levels. The result is a building that uses up to 35 % less energy than
RACA Journal I July 2026 comparable structures in the area, without relying on energyintensive HVAC systems.
The lesson for designers? Observe, understand and adapt the environment rather than fight it. By studying how animals manage heat, conserve energy and regulate their internal environments, architects can develop buildings that are inherently more efficient. This might include optimising natural ventilation paths, enhancing insulation or designing thermal mass that absorbs and releases heat at the right times.
Rohr also shared how this thinking translates to modern hybrid systems, such as the ASHRAE headquarters in Atlanta. By combining radiant hydronic heating and cooling with forcedair ventilation, the design team created a system that responds efficiently to changing occupancy and weather conditions. The building’ s envelope was optimised to reduce energy demand from the start – less glass, more insulation and smarter orientation – so that mechanical systems only needed to supplement, not dominate, the building’ s energy balance. Solar panels completed the zero energy equation, providing locally sourced renewable energy to offset what little the building consumes.
The lesson is clear: nature is a blueprint for efficiency. Whether it’ s mimicking the cooling ears of elephants, the insulation of polar bears, or the self-regulating mounds of termites, Rohr encourages designers to look globally and locally for inspiration.“ Adapt your site first. See how animals and nature solve thermal problems and incorporate that thinking before you even turn on a single machine,” he advised.
Biomimicry isn’ t just a novelty, it’ s a pathway to buildings that consume less energy, provide more comfort, and coexist with the environment rather than fight it. As Rohr puts it,“ The cleanest energy is energy unused. If we can design buildings that naturally need less, we can make a real difference.”
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