Inspired by nature

Biomimicry inventors tackle environmental problems

  • Jay Harman of PAX Scientific with a lab-created vortex.

    Sandy Huffaker
  • Rolf Muller and Judy Muller-Cohn have discovered a way to stabilize lab samples without refrigeration.

    Sandy Huffaker
  • Brent Constantz, of Calera Co., has invented a technology that sequesters CO2 from power plants in cement.

    Sandy Huffaker
  • Water Bear

    Bob Goldstein, UNC

What if we could solve big environmental problems simply by shifting our approach -- from relying on human cleverness to mimicking nature? What if architects studied how bees build hives to design sturdier, lighter skyscrapers, and chemists figured out how mussels attach to rocks to create stronger, nontoxic adhesives?

This is the premise of biomimicry: Solutions to our most intractable problems already exist in nature and are waiting to be copied. Leonardo da Vinci and the Wright brothers, for example, studied bird flight and drew up designs for the first aircraft. Alexander Graham Bell modeled the telephone receiver on the human ear. Now, a new generation of inventors is systematically examining the natural world to address every-thing from transportation to climate change.

Many of these inventors and entrepreneurs are in the West, especially in California. Their claims are startling -- "if these inventions were fully adopted, we could save one-third of the energy used on the planet" -- but many scientists and entrepreneurs see real promise in biomimicry. The following three inventors and their projects illuminate the possibilities of this emerging discipline.

Jay Harman PAX Scientific, San Rafael, Calif.
Invention Fans, pumps and propellers
Inspiration Spiral shapes everywhere in nature

Since his childhood in Australia swimming in the ocean, spear fishing and building primitive boats, Jay Harman, 60, has been observing the relationship between shape and movement in nature. He noticed something extraordinary: From nautilus shells to tornadoes, flow in the natural world moves in spirals. Engineers, though, typically design propellers, fans and pumps as if a straight line is the path of least resistance.

Harman spent 20 years trying to reverse-engineer a whirlpool, which he eventually did by making a cast of the vortex formed when water flows down a bathtub drain. Quantifying its exact shape took a few more years, but gave him a mathematical guideline for translating the efficiencies of natural spirals into industrial applications.

Such spirals share identical geometry. The shape allows the most efficient flow of liquids and gases, reducing the amount of turbulence in air or fluid and minimizing the energy required to generate and maintain flow.

After moving to California, Harman founded PAX Scientific in 1997 to bring his spiral inventions to market. ("Pax" is Latin for "peace.") He's since spun off companies to pursue applications in different industries, including PaxFan, PaxMixer and PaxAuto.

Pumps use 30 percent of the world's electricity, Harman says, and PAX pumps are 12 percent more efficient than the next best available. PAX refrigerator fans are 25 percent more efficient than conventional refrigerator fans. The most widely adopted PAX invention so far is a water mixer that circulates municipal water supplies, in use in roughly 50 U.S. cities and elsewhere throughout the world. It uses 80 percent less energy than conventional mixers, and reduces chemical use by 85 percent. PAX air conditioners, heat exchangers and wind turbines offer similarly dramatic improvements.

After years of promotion, though, Harman's designs remain largely obscure; the large energy savings and greenhouse gas reductions he says his products could bring have yet to materialize. Cheap energy has worked against him, he says, but the biggest barrier is that companies are reluctant to adopt technologies their engineers don't understand.

But things may finally be shifting Harman's way. PAX Scientific formed a research partnership with Cascade Technologies and Stanford University to independently evaluate its designs, confirming the technology's substantial performance improvements compared with traditional designs. Now, rising energy prices, climate change and the global economic crisis are pushing companies toward his products, Harman says. "Fully adopted, the world can save, probably, a third of its energy bill, and that means a third less CO2 emissions," he says.  "It's the only way to go."

Judy Muller-Cohn and Rolf Muller
Biomatrica Inc., San Diego, Calif.
Invention Stabilizing biological samples without refrigeration
Inspiration Water bears (microscopic, eight-legged animals often living on mosses and lichens)

Unless you are a molecular biologist, you may not know that you can buy freezers designed to stay at -80 degrees C with alarms that blare during malfunctions. These freezers are made for scientific labs -- at universities, biotechnology and pharmaceutical companies, medical and forensics laboratories and elsewhere -- that rely on cold storage to protect fragile samples of DNA, RNA, proteins and other biological materials.

But multiple freeze-thaw cycles, warming for manipulation, and accidental thawing often degrade or ruin samples; it's expensive for labs to buy and operate freezers; and the environmental costs of cold storage are high.

Entomologist Judy Muller-Cohn and her husband, Rolf Cohn, a molecular virologist, spent many years working in molecular science labs -- and cursing freezers. One night 13 years ago, when Muller-Cohn was working for a biotech company, a broken freezer destroyed more than 1,000 of her valuable samples. Meanwhile, in a different lab, her husband was buying one freezer after another to chill his ever-increasing DNA and RNA samples, ultimately spending nearly half a million dollars.

The couple started thinking about extremophiles -- organisms that thrive in extreme conditions such as severe cold or heat. How do such creatures cope? A tiny aquatic organism called a tardigrade, or water bear, survives dry periods by secreting a dissolvable matrix that wraps around its DNA, protecting it. When the tardigrade gets wet again, up to 120 years later, the matrix dissolves and the creature returns to life.

John Crowe, a UC Davis scientist, had studied tardigrades since the 1970s. The couple built on his work, creating synthetic structures that mimic the water bear's protective molecules. Their synthetic molecules protected DNA at room temperature, and they could restore the samples for use and analysis by adding water. They developed kits for scientists, and in 2006, they founded Biomatrica, which now sells kits to thousands of labs throughout the world. Qiagen, the largest DNA purification company in the world, has licensed two Biomatrica products, and they have recently been accepted into several large labs.

Over the next 10 years, Stanford University has estimated that it could save 40 million kilowatt hours of electricity, 18,000 metric tons of greenhouse gas emissions and 16 million dollars by adopting Biomatrica's technology in its 350 biological research labs. With the explosion of genomics research in fields ranging from archaeology to genetic engineering, the estimated $34 billion market for Biomatrica's products is growing all the time. "Wherever there's DNA or RNA or proteins," Muller-Cohn says, "there's an application for this."

Brent Constantz Calera Corporation, Los Gatos, Calif.
Invention Concrete that sequesters carbon dioxide
Inspiration Reef-building corals

Most experts agree there's just no easy way to avert climate change. Brent Constantz, however, has an idea. A biomineralization expert affiliated with Stanford University, Constantz invented a biomimetic process that could neutralize two of the largest sources of manmade CO2 emissions -- power plants and cement production.

A geologist and former Rhodes scholar, Constantz, 51, didn't start out to save the planet. As a Ph.D. student, he studied how corals make reefs from the calcium carbonate in seawater. His understanding of the process led him, at 27, to invent bone cement that revolutionized bone-fracture repair. After selling his bone-cement companies in the 1990s, Constantz taught geology at Stanford. Motivated by learning that cement production is the third-largest source of anthropogenic CO2 worldwide, he says, "It took me a very short period of time to come up with a way to make cement in a biomimetic fashion, similar to my old cement."  He filed a few patents and, with backing from the billionaire venture capitalist Vinod Khosla, started Calera Corp. in 2007.

Conventional cement production requires massive energy input to heat limestone to 1,400 degrees C. In contrast, Constantz' process, the details of which are patented, involves running power-plant exhaust through seawater. The CO2 and other pollutants combine with calcium and magnesium to form synthetic limestone, which is processed into cement or aggregate, the main ingredients in concrete and asphalt. Other byproducts are fresh water and clean air.

Calera's technology removes 90 percent of the CO2 from power-plant emissions and converts it to carbon-negative cement. (Each ton of Calera's cement sequesters half a ton of CO2.)  The trick, Constantz says, is that he's mimicking something that requires no energy input: Corals make reefs by utilizing a passive process in which calcium carbonate precipitates out of super-saturated seawater. Calera cement is also cheaper to make than conventional Portland cement. This lower cost is one of the things that convinced Khosla to invest in Calera. To succeed, new technologies have to be cheaper first and greener second, Khosla says, and this product is both "dramatically cheaper and dramatically greener."

Calera's first pilot plant began operating in 2008 next to a natural gas-fired power plant on the California coast near Moss Landing. A second, larger plant began operating there on Jan.1. In December, Calera announced an alliance with Bechtel, a worldwide engineering and construction firm, to bring the technology to the global market.

Constantz and his company are attracting a lot of notice. Former Sierra Club President Carl Pope calls the technology a "game changer." Scientific American, Popular Science and the Engineering News-Record, a construction industry magazine, have all written glowingly of Calera's potential. The potential impact is huge: Currently, electricity generation accounts for 35 percent of human-caused CO2 emissions, while cement production accounts for another 5 percent.

Some skepticism, or at least hesitation, is coming from building engineers, however. Rich Bohan of the Portland Cement Association cautions that any new material would have to get incorporated into building codes. Tom Pyle, an engineer on California's Climate Action Team, says in an e-mail that the state is willing to test Calera's product to determine if it meets its aggregate standards. Calera has recruited Terence Holland, a past president of the American Concrete Institute, to help get the product accepted by the concrete industry.

Calera has pilot projects in Australia and Dubai, and is discussing projects in other locations around the world. Constantz is confident that he will prove that Calera's technology is technically and commercially viable. Whether it can be scaled up quickly enough to successfully combat the planet's immense CO2 problem and fulfill our growing appetite for cement is still unknown.  Constantz says that even without greenhouse gas regulation, power plants are eager to partner with his company, because along with CO2, Calera cement stores all the sulfur dioxide, nitrous oxide, mercury and arsenic from flue gas, "and we think the roadways are a much better place to sequester all that stuff than anywhere else."

Carla A. Wise is an environmental and science writer based in Corvallis, Oregon.