Turning to Nature to Save Energy
November 13, 2007
At the beginning of the industrial age, mankind marveled at the inventions being developed. Clearly, humans sat atop the food chain and the machines they designed were modern miracles. For the next century, designers and engineers used an “industrial model” to create machines aimed at increasing productivity. Little, if any, consideration was given to using a “biological model” that borrowed from nature. That meant that most engineers believed machines had to get more and more complex in order to become more and more effective. In recent years, that situation has changed dramatically. The industrial model has fallen out of favor and the biological model is on the rise. We’ve finally figured out that borrowing rules from nature, the rules it has used to generate countless systems and designs, produces better results than trying to engineer rules of our own. Nature has managed to evolve by organizing living organisms into ever more complex systems. “If there’s anything more remarkable in nature than its complexity,” marvels Robert Frenay, “it’s how gracefully it is organized – that such an unimaginable number and diversity of life forms somehow behaves as a coherent system.” [Pulse: The Coming Age of Systems and Machines (New York: Farrar, Straus and Giroux, 2006), p. 167.]
BusinessWeek reports that designers are now looking to nature to help save energy by using natural shapes and materials to help reduce friction [“Saving Energy by Fighting Friction,” by Stephen Baker, 5 November 2007]. Baker writes:
“Have you ever tried drinking a milkshake through a skinny straw? It can leave your cheeks burning for a piddling payoff. Replace it with a fatter straw, and the cheeks barely have to work at all. Why such a difference? Friction. The liquid rubs the straw. And that same force slows the traffic in all kinds of pipes throughout our economy. Strange as it may sound, the energy implications of skinny pipes are huge: More than one-quarter of the electricity consumed by American industry powers pumps and fans that push along stubborn gases and liquids. So the need for shorter, squatter tubing has never been greater. Fat pipes are part of a barely recognized industry that may soon become much more prominent: friction fighting. Estimates indicate that overcoming resistance accounts for as much as one-third of the energy we consume on the planet. Now, with oil topping $80 per barrel, the cost of each rub, chafe, or blast of headwind is soaring. But such costs also bring opportunities for those with high-tech fixes.”
We may long for the day when oil was “just” $80 per barrel. In the weeks since Baker first wrote his article, oil prices have soared. As a result, the energy savings he discusses have become even more important.
“The fight against friction is moving from garages and fix-it shops right into strategy sessions in the corner office. It’s driving innovation across the global economy. New nanotechnologies, for example, combat the rubbing and clinging of objects in motion with ingenious thin coatings and ball bearings barely the size of molecules. Chemical giants such as DuPont and BASF, leaders in the $40 billion lubrication market, are developing new polymers and low-friction plastics for car engines and airplanes. And design shops, like Rumsey Engineers of Oakland, Calif., are installing–you guessed it–fat pipes. The company recently used them to double the efficiency of the air-conditioning system at the Oakland Museum. ‘We cut friction in half,’ says company President Peter H. Rumsey.”
Baker goes on to note that designers are increasingly turning to nature to discover how it has dealt with the problem of friction.
Designers in the battle against friction draw lessons from the streamlined forms of plants and animals. One team at Mercedes-Benz , for example, has modeled a concept car on the smooth-swimming form of a boxfish. The ‘Bionic’ car slices neatly through strong winds on the open highway. Better aerodynamics leads to cars that get 70 miles per gallon of gas, according to Mercedes, 30% more than a standard design. The opportunities for savings are even greater in trucks. When they’re rolling at highway speeds, they burn two-thirds of their fuel just to overcome the drag of wind. Researchers at Georgia Tech report that streamlining truck design could reduce this drag by 12%, saving 1.2 billion gallons of fuel per year in the U.S.”
No one has ever accused the lowly boxfish of being particularly handsome, which is probably why it attracted the eye of designers. “Why,” they must have asked, “did nature create this particular shape?” Sharks, for example, appear to have a much more aerodynamic shape than the boxfish, but it turns out that the fish’s boxy shape does indeed have great friction-reducing properties. If the design leads to cars that actually achieve 70 miles per gallon, I’ll bet it starts looking a lot more attractive to consumers.
Scientists, Baker reports, are looking beyond design to the nature of materials themselves — especially at the molecular level.
“The nanotech players focus mostly on new substances. ApNano Materials makes chemical spheres called fullerenes, each one so small that several billion scarcely fill a single teaspoon. When blended into traditional motor oils, these balls leave a smooth film several atoms thick on the metal they touch. Tests by Israel’s technical institute Technion show that they can reduce friction by as much as 50%. ApNano founder Menachem Genut says his fullerenes will be available as an additive in name-brand fuel oil within a year. At DuPont’s giant Experimental Station in Wilmington, Del., friction is an age-old adversary. (Teflon, first developed to fight this problem on frying pans, later turned up as a lubricant in jet engines.)”
I read somewhere that Teflon was accidentally discovered while DuPont was looking for an alternative form of Freon and that its non-stick properties were a side effect. One of DuPont’s innovative thinkers saw an alternative use for the substance and non-stick cooking was born. Historical product development is often intriguing and Baker goes on to discuss how a Cold War DuPont creation is making a comeback.
“In the late 1950s, researchers at DuPont commercialized a molecule with astounding properties. It held up even in furnace-like conditions where lesser lubricants broke apart. They called it Krytox. The only trouble: Since it was produced from calcium fluoride, a mineral that’s expensive to mine, Krytox cost too much to make. DuPont shelved it. But in 1967, a buyer finally surfaced: Following a deadly fire during a launchpad test, NASA needed a nonflammable lubricant that could withstand tremendous heat. Krytox is still pricey. In some forms it can cost more than $1,000 a pound. But its market is growing in double digits, and far beyond NASA. Why? Automakers face a host of challenges that demand better lubrication. First, they’re under pressure to build hotter engines, which are far more fuel-efficient than cooler ones, but harder to lubricate. At the same time, today’s engines are lighter and smaller, which leaves less room for the flow of cooling air. These sizzling engines must do their work quietly–a key selling point for luxury cars–and must make good on the common 100,000-mile warranty. To meet such specs, automakers are paying top dollar for Krytox and dabbing key components with the Space Age oil. It’s as if the world’s awakening to the costs of friction, says DuPont’s Senior Engineer Carl Walther. ‘The market’s coming to us.'”
Nature learned long ago how to evolve to conserve energy, including strategies and designs to reduce friction when required. Innovations will continue to come from discoveries found in nature, including coping strategies. We just need to be smart enough to look past things like the unattractive shape of the boxfish to discover the secrets hiding in nature. In my company’s business, which centers on rule set automation, we search for the simplest rule that achieves a desired result. Researchers have found that computer models following very simple rules can create some very complex behavior — just like in nature. Who would have imagined?