Long before her research pushed the limits of nature, the renowned chemical engineer was a typical teenager challenging her parents in high school by moving into an apartment and moonlighting as a cocktail waitress just to pay the bills.
When America joined the war in Vietnam, Arnold, now 59, hitchhiked from Pennsylvania to Washington, D.C. to join protests appealing to end the violence.
“This was a time when young people looked for alternatives to the way things are normally done,” said Arnold, a professor at Caltech. “I’m hoping young people feel that today.”
Lives may depend on it.
These days, there’s a quieter battle emerging – one that won’t be won in jungles with armies and bullets.
Instead, it will play out in laboratories with scientists like Arnold and research that’s opening the door for future generations to save the Earth by replacing coal and oil with cleaner, renewable energy made from corn and other plants.
It’s called biofuel, and it’s going to change the way we live – whether we like it or not.
Of that quota, 85 percent must come from a mix of ethanol and cellulosic material such as wood chips and grasses.
These types of fuels have been known to emit less pollutants and greenhouse gases than their petroleum counterparts, stonewalling the progression of global warming.
A study completed by the National Renewable Energy Laboratory, cited by the U.S. Department of Energy, found that greenhouse gas emissions for biodiesel were more than 52 percent lower than those from petroleum diesel.
Despite the environmental benefits, however, biofuels still present a host of dilemmas.
For one, there’s supply and demand.
In 2014, less than 2 percent of the mandated amount of cellulosics were produced as the industry failed to get off the ground.
A United Nations expert once called biofuel production a “crime against humanity” for allegedly driving up the price of food, contributing to worldwide hunger.
After all, ethanol is a product of corn, which is used to feed both livestock and humans.
Ethanol isn’t cheap to produce, either, due to the cost of harvesting and processing a crop that’s spread out across the country.
Those costs, of course, get passed onto the consumer.
Meanwhile, the price of oil has plummeted to roughly $40 per barrel offering little incentive for biofuel to become a feasible alternative.
“How can you compete with nearly free oil?” Arnold asked. “The feed stocks for biofuels are diffuse. They’re spread out all over and it costs money to collect them together.”
The key, she added, is making biofuel production more efficient.
That’s where Arnold’s research comes in.
In the 1990s, she pioneered the idea of “directed evolution,” a method of developing proteins using a type of lab-controlled natural selection through random mutations, which can be used to create – or “evolve” – proteins capable of a specific function.
Proteins spawned from this technique can be found anywhere, from glucose sensors for diabetics to more common household products.
For example, many laundry detergents contain stain-removing enzymes “evolved” to clean your clothes.
Arnold’s experiments take a system nature has created and re-engineer it to develop microorganisms to improve the production of biofuel.
“Bacteria are very good chemists,” Arnold said. “Why shouldn’t they do chemistry for us?”
It’s this thinking that earned Arnold the 2011 National Medal of Technology and Innovation, awarded by President Barack Obama, along with a host of other accolades.
But her research wasn’t always as lauded as it is now.
Early on, Arnold faced critics for her technique, which included performing hundreds of experiments using random mutations, breeding generations of bacteria until she found one that could do the job.
“It’s not science. Gentlemen don’t do random mutations,” she was once told.
“Back then, I was proposing a very different way of engineering biological systems, admitting it was too complicated to design,” Arnold said. “It’s human nature to want to go in and engineer based on knowledge.”
As a whole, the basis of the experiments – using tiny organisms as worker bees in the production of fuel – isn’t that unique.
For years, the ethanol industry has used yeast to break down sugars in corn to yield fuel, Arnold said, adding that “the more advanced approach is to make fuels that are perhaps better than ethanol.”
In 2005, Arnold co-founded Colorado-based Gevo Inc., a leading researcher and producer of this four-carbon alcohol that boasts a broader range of uses than ethanol, which is mostly used for automobiles.
According to Gevo’s website, isobutanol – created using patented fermentation methods – can be mixed with gasoline or turned into other products, including jet fuel or butenes, another chemical commodity.
At its plant in Minnesota, Gevo aims to produce 750,000 to 1 million gallons of isobutanol in 2016, though it still has a long way to go before becoming the standard.
“Once again, the reason that this is not the next Exxon is that the price of the feedstock – what goes into the process – is still high relative to the cost of oil,” Arnold said.
Can people be convinced to pay the higher price?
Outside the science, Arnold said, there are other – albeit less gentle – ways to make biofuel more competitive.
In other words: learning the hard way.
By then it might be too late.
“Until we pay the real costs of pumping oil out of the ground and dumping it into the atmosphere – global warming and everything else – it is hard for biofuels to compete,” Arnold said.