A group of designers claim they have solved the problem of air conditioners using high levels of energy simply by mimicking the craftiness of nature.
Biologist, innovation consultant and author of a book on biomimicry, Janine Benyus, believes that copying the way plants and animals solve natural problems can provide many benefits, from environmental sustainability to economic efficiency.
“With biomimicry, we’re able to apply fresh thinking to traditional manufacturing, to undo the toxic and energy-intensive mistakes of the past,” she said.
Benyus is part of a group that hopes to lead a revolution in design by imitating nature, mirroring the way of natural systems, in which nothing is wasted as everything can be used by something else.
For example, instead of using large inputs of energy and toxic chemicals to make things and ship them across the globe, nature makes what it needs where it needs it, with water-based chemistry.
These designs suggest some of what could be learned by applying the lessons of biomimicry to the problem of air conditioning in particular.
Ventilation inspired by termites
Perhaps the most famous example of biomimicry when it comes to heating and cooling is ventilation inspired by termites.
A few years ago, scientists observed that big termite mounds in Africa stay remarkably cool inside, even in blistering heat.
The insects accomplish that feat with a clever system of air pockets, which drive natural ventilation through convection.
Architect Mick Pearce and engineering firm Arup borrowed that idea to build Eastgate Centre, a large office and shopping centre in Zimbabwe that is cooled with outside air.
The system uses only 10 per cent as much energy as conventional air conditioning to drive fans that keep the air circulating.
Countercurrent heat exchange inspired by birds
Ducks and penguins that live in cold climates have an innovative adaptation that helps them survive the elements.
The veins and arteries in their feet have a countercurrent configuration, which ends up warming the blood that is closer to the animal’s core and cooling the blood at the edges of its extremities.
By keeping cooler blood closer to the snow and ice, such birds lose less body heat overall.
Clayton Grow, author of The Writing Engineer blog, has pointed out that shell tube heat exchangers in industrial-scale heating and cooling systems use a similar type of flow pattern to maximise efficiency.
Moisture absorption inspired by ticks
Grow notes that liquid desiccant dehumidifiers systems also seem to follow a form of biomimicry.
These systems are designed to pull humidity from the air inside a building (traditional air conditioning also reduces humidity).
It uses a liquid salt solution, something similar to what the brown dog tick secretes to absorb water from the air.
Efficient fans inspired by tornadoes and whirlpools
A company called PAX Scientific – which has as its slogan 'Capturing the Force of Nature' – is marketing a fan based on the logarithmic spiral shape found in such phenomena as tornadoes, whirlpools and even airflow in the human trachea.
The company says the fans have lower turbulence and higher efficiency for cooling.
Efficient fans inspired by whale flippers
In another take on better fan design, a start-up called WhalePower is developing fan blades that produce greater lift, and therefore move more air, thanks to the bumpy design of a humpback whale’s flipper.
WhalePower says its fans move 25 per cent more air than conventional fans while using 20 per cent less energy.
The company is also working on more powerful wind turbine blades.
Source: National Geographic