Biological organisms have phenomenal ways to generate or regulate the conditions necessary for survival. In my previous post, I talked about how materials science can leverage designs found in nature to solve some of our most complex problems. Today, I’m looking at the sustainability found in natural configurations. When it comes to realizing a sustainable energy future, nature holds a number of designs that set the stage for biomimetic inspiration. Below are a few examples of how this concept is being put into action:
Termite mounds have inspired natural climate controls for green building design. Certain species of termites found in Africa build mounds that can reach heights exceeding 30 feet. In these areas, daily temperatures fluctuate between excesses of 100°F to below freezing, but termites sustain a constant internal temperature in the mound. They do so by digging complex ventilation tunnels connecting chimneys to vents at the base that are opened or closed to regulate the internal temperature. The Eastgate Centre in Zimbabwe is modeled after a termite mound and does not have conventional air-conditioning systems. Compared to conventional buildings, the building uses 10% less energy, allows tenants to pay 20% less rent, and has saved the building owners $3.5 million in the first five years by avoiding the need for a commercial air-conditioning system.
Hydrogenase enzymes have inspired new solar energy generation techniques for the sustainable production of hydrogen fuel. Hydrogenase enzymes are natural proteins that produce hydrogen from protons and electrons. Compared to platinum used in conventional fuel cell catalysts, the mimicry of hydrogenase represents a desirable new approach for greater affordability and abundance. Scientists are interested in mimicking the functionality of hydrogenase for a new type of solar energy generation by integrating the resulting technology into solar assemblies that use light to split water into hydrogen. The cheap, efficient production of hydrogen fuel represents a milestone in transitioning away from petroleum-based fuels and toward a sustainable, alternative fuel-based economy.
Aquaporin proteins have inspired water filtration membrane designs for efficient water desalination techniques. In the face of increasing scarcity of freshwater resources, researchers are seeking alternative methods to remove salt (i.e., desalination) and contaminants from seawater. Compared with conventional wastewater treatment techniques, water desalination is often cost-prohibitive and inefficient, requiring up to 10 times the energy consumption to produce potable water. Aquaporin proteins are like plumbing systems for biological cells. They form pores in cell membranes that allow water to pass through and circulate around the cell while filtering out foreign solutes. By mimicking the pore size and surface chemistry of membranes formed by aquaporin proteins, bio-inspired water filtration membranes could significantly lower the cost and energy requirements of desalination. This would effectively position Earth’s oceans as a practically infinite source for clean water production.
These bio-inspired design approaches share a common theme: they use significantly less energy than their traditional counterparts. If we are truly interested in moving toward a sustainable energy future, then biomimicry of nature’s sustainable designs will be a key component.