Hey there!

It’s that time of year again (and no, I’m not talking about the pre-Christmas spirit). My garden is already tucked in for the winter, covered in its first layer of snow. Looking at it, I felt inspired to share some thoughts on a fascinating field of biomimetics. Recently, while presenting a keynote on biomimetics, I showcased a diagram by the Plant Biomechanics Group Freiburg illustrating different areas where biomimetics can be applied. Though insightful, I find the diagram somewhat outdated, so I usually suggest adding two fields that I believe deserve inclusion: Sustainability and Energy Biomimetics. Today, I’d like to dive into the latter—Biomimetics in Energy Systems.

What Is Biomimetics in Energy Systems?

If you search online for biomimetics in energy, you’re unlikely to find much practical information on how it could help develop alternative ways to harness and convert freely available energy into useful forms. Yet, this is precisely the kind of innovation we need as we move away from fossil fuels and search for sustainable solutions. Governments have declared the need for an energy transition, and industries are under pressure to deliver—but existing technologies often fall short of true sustainability (and no, photovoltaics aren’t fully sustainable either—that’s a discussion for another time). Could Biomimetics in Energy Systems point the way forward?

Let me explain what this field is all about with a personal story, one that connects to my love of gardening and my desire to create a sustainable winter greenhouse.

Lessons from the Australian Brushturkey

Gardening is my passion. I enjoy growing vegetables and preserving them for winter. Last year, I bought a greenhouse to extend the growing season, but I dreamed of something more: an all-year-round growing season, even during Villach’s cold alpine winters. To achieve this, I needed a heating system—but not just any system. I wanted a passive solution that worked without electricity or wood burning, one that required no elaborate installation or ongoing costs.

Then, I remembered a university lesson on energy biomimetics and the ingenious strategy of the Australian brushturkey (Alectura lathami), also known as the bush turkey. These birds build mounds of leaves that, when exposed to the right conditions (humidity and temperature), begin to rot. As microorganisms break down the organic material, heat is generated—a natural furnace powered by the sun’s energy stored in organic matter via photosynthesis.

This concept sparked an idea: Why not use the same principle to heat my greenhouse?

The Hot Compost Experiment

I began researching hot composting, a process that generates significant heat by combining organic materials in the right proportions. Carbon-rich materials (like straw and leaves) and nitrogen-rich materials (like manure and grass clippings) break down together under optimal moisture conditions, creating temperatures that can soar to 70°C (158°F).

Excited by the potential, I set up a hot bed in the center of my greenhouse. I fenced off an area and layered organic materials “lasagna-style,” dampening each layer to maintain moisture. To maximize heat utilization, I placed a water-filled barrel next to the pile, hoping it would absorb and release warmth during the night.

Three days later, the results were in: it worked! The compost pile’s internal temperature rose above 50°C (122°F), even as outdoor temperatures dipped below freezing.

Challenges and Successes

However, this success wasn’t without its hurdles. After a week, the pile’s temperature dropped to 30°C (86°F) as the nitrogen in the material was depleted. Without a fresh supply of chicken manure, I couldn’t sustain the heat. Additionally, the greenhouse’s heat loss outpaced the warmth generated by the compost, making Plan A—heating the entire greenhouse—impractical.

But Plan B saved the day. The remaining heat was enough to maintain about 20°C (68°F) in the center of the pile and 10°C (50°F) at its surface. I added a mesh frame, soil, and seeds on top of the pile. The warm microclimate was perfect for sprouting seeds, and by mid-January, we were enjoying fresh arugula and radish leaves.

While not a perfect solution, I consider the experiment a success. It demonstrated how biomimetic principles can inspire innovative approaches to energy use, even on a small scale.

Rethinking Energy Through Biomimetics

This project was more than a gardening adventure—it was a real-life exploration of Biomimetics in Energy Systems. If a compost pile can heat a greenhouse, imagine the possibilities at larger scales: bio-inspired heating systems, passive solar designs modeled on termite mounds, or wind turbines designed like bird wings. Nature offers countless examples of efficient energy use, waiting for us to adapt them.

As the world searches for alternatives to fossil fuels, biomimetics could lead the way. It’s not just about copying nature but about learning how to work with the principles that have powered life on Earth for billions of years.

Final Thoughts

This winter, my greenhouse experiment won’t make a comeback (slugs found it way too cozy last time, and I need the space for other uses). But it left me with valuable insights—and some delicious midwinter greens.

So, as you look at the snow or tend to your garden, remember the ingenious strategies of nature, from bush turkeys to compost piles. Who knows? You might uncover an idea that changes the way we think about energy systems entirely.

Anja