42 www. refrigerationandaircon. co. za RACA Journal I July 2026
BIOMIMICRY technical
BEYOND BIOMIMICRY: MODERN STRATEGIES FOR ZERO ENERGY BUILDINGS Designing zero energy buildings involves more than mimicking nature. Rohr explains that it also requires a deep understanding of energy terminology, thoughtful system integration and practical trade-offs in building design.
Rohr emphasises the importance of sorting through buzzwords that often confuse stakeholders. Terms like electrification, carbon-neutral, zero emissions and zero energy buildings each have specific meanings:
• Electrification is the shift from direct combustion fuels to electricity, ideally paired with renewable sources.
• Carbon-neutral or decarbonised depends heavily on boundaries – what energy sources count, and where emissions occur.
• Zero emissions refers to a building or system producing as much energy from renewable sources as it consumes.
• Zero energy buildings( ZEBs) minimise energy demand through efficiency and then meet remaining needs with renewable energy.
Rohr notes that efficiency is the foundation:“ You can’ t just slap a billion solar panels on a leaky, inefficient building and expect it to
work. Reduce the energy needed first, then balance the equation with renewable energy.”
THE CHALLENGE OF MODERN ARCHITECTURE Modern architecture often conflicts with energy efficiency goals. Rohr humorously contrasts two extremes: a glass skyscraper with stunning views but high energy demand, versus an underground cave with constant natural temperature but no sunlight. While the cave is energy-efficient, it’ s impractical for most office environments. The takeaway: architecture often drives energy demand, and engineers must innovate to reduce it within realistic design constraints.
Rohr shares lessons from his early experiences in hydronics versus forced-air systems, once considered rival trades. Today, buildings require hybrid approaches, combining radiant heating / cooling and forced-air ventilation. Radiant systems efficiently handle sensible loads, while forced air manages latent loads like humidity.
Standards such as ASHRAE 62.1( ventilation) and 55( thermal comfort) provide boundaries that prevent issues like condensation or discomfort, enabling hybrid systems to work in tandem. Additionally, ASHRAE Standard 90.1 guides energy-efficient design for building envelopes and system performance. RACA
Ingeborg Korme | Unsplash
Termites construct complex mounds that self-regulate temperature through passive ventilation.
42 www. refrigerationandaircon. co. za RACA Journal I July 2026