It Takes One (Times 6 Billion): Solving the Global Energy Challenge

Daniel Nocera, Patterson Rockwood Professor of Energy at Harvard University, gave a lecture at Tulane on Sunday, Feb. 14 addressing his research on the chemistry of renewable energy and its potential to solve what he calls the global energy challenge.

The challenge for science in the 21st century, Nocera explained, is meeting energy demands as the world’s population continues to grow dramatically. Current estimates vary, but stark projections from the UN say the population could double by the year 2100. Furthermore, developing countries will  experience the most growth and thereby fresh challenges to their infrastructure.

“We’re going to have this huge energy need, and when you start looking at all the numbers, there’s only one supply that has scale, and it’s the sun,” Nocera said in an interview with MIT Technology Review.

Nocera’s vision is one of “personalized energy,” a fundamental change to the energy production system we rely upon today. Currently, a power grid manufactures huge amounts of energy which is distributed to many individuals, but Nocera believes this cannot sustain exponential population growth. His solution lies in what he calls the “artificial leaf,” the result of years of research. An unassuming device, the artificial leaf was inspired by the elegant chemical logic of photosynthesis, a process by which plants harness solar energy to fuel their cells.

Nocera’s artificial leaf is composed of a thin silicon layer coated in metal catalysts. It sits in a jar of water and as the sun strikes it, the silicon leaf catalyzes the splitting of water into its hydrogen and oxygen components. Gases bubble out from the leaf, and are ultimately harvested as a source of energy for fuel cells. The power of the artificial leaf is its ability to power fuel cells discretely. With up-scaled production, billions of artificial leaves could uproot the power grid infrastructure, allowing individuals to power their own homes efficiently and sustainably.

“You don’t build bigger and bigger artificial leaves,” Nocera said in a General Electric sponsored Focus Forward video. “I’m just going to build more and more.”

Nocera said he will travel to India next week to meet with the Prime Minister and discuss implementing his technology there, the second most populous country in the world after China.

The Tulane Department of Chemistry invited Nocera, in keeping with its annual Hans B. Jonassen lecture series honoring longtime Tulane professor Hans Jonassen and his contributions to both the Tulane community and inorganic chemistry.