U.S. Energy Secretary Steven Chu expressed optimism Thursday (June 4) that the world will avoid catastrophic climate change, saying the crisis presents an opportunity to bring about a sustainable energy future.

“If there ever was a time to help steer America and the world towards a path of sustainable energy, now is the time,” Chu said. “The task ahead is daunting, but we can and will succeed.”

Chu delivered his remarks as the speaker at Harvard’s 358th Commencement, held outdoors in Harvard Yard’s Tercentenary Theatre. As is traditional, Chu spoke at the annual meeting of the Harvard Alumni Association during Commencement Day’s Afternoon Exercises. In his speech, Chu called on Harvard’s latest graduates to help fight climate change by inventing new technology, designing better government policies, and making businesses environmentally sustainable.

“The Obama administration is laying a new foundation for a prosperous and sustainable energy future, but we don’t have all the answers. And that’s where you come in. I am asking you to join this effort,” Chu said. “As our future intellectual leaders, take the time to learn more about what’s at stake, and then act on that knowledge. As future scientists and engineers, I ask you to give us better technology solutions. As future economists and political scientists, I ask you to create better policy options. As future business leaders, I ask that you make sustainability an integral part of your business.”

Chu was one of several speakers who took the podium Thursday, a day filled with speeches, music, and tradition dating back hundreds of years. The University granted 6,777 degrees and 81 certificates, swelling the ranks of the Harvard Alumni Association, which has more than 300,000 members worldwide.

The morning’s exercises included student speeches and the conferring of degrees by Harvard President Drew Faust. It featured a rendition of “America the Beautiful” by jazz trumpeter Wynton Marsalis, who received an honorary doctor of music degree.

In her annual speech to the Alumni Association Thursday afternoon, Faust reflected on the difficult year the University has endured. Harvard was not spared in the global financial meltdown and has been forced to take a new, hard look at its spending priorities as it examines ways to cut its budget.

Despite the difficulty, Faust said, this is not a time to feel victimized by circumstances or to forget Harvard’s long history of academic excellence — an excellence that may be more in need today than ever before.

Instead, it’s time to re-examine the University’s priorities and renew the institution’s dedication to three core principles: that equal opportunity has to be available to talented students regardless of their economic means; that universities are critical generators of knowledge, so new ways to conduct and support research must be found; and that universities must be places that speak the truth — through their research and knowledge — regardless of whether that particular truth is popular at the time.

“Change can happen to us or through us,” Faust said. “We must make sure we become its architects, not its victims. We must ask ourselves what it is we want to be on the other side of recession and crisis, when the world has reached what we might call a new normal.”

Potential savings from efficiency

In his talk, Chu said that though many of the answers to America’s — and the world’s — energy problems remain to be found, some are already apparent.

Energy efficiency alone could garner enormous savings, he said. Using current technology, buildings could be made 80 percent more efficient, paying back the needed investment in just 15 years. Since heating, cooling, and powering buildings account for roughly 40 percent of our energy consumption, those savings alone could be considerable. Energy efficiency has such enormous potential for savings, Chu said, it doesn’t even qualify as low-hanging fruit, calling it instead “fruit lying on the ground.”

Some of the answers to the energy crisis are not known, of course. To find those, the Obama administration is encouraging research and innovation, Chu said, adding that America has the opportunity to lead in the development of a new industrial revolution.

“We will invent much-improved methods to harness the sun, the wind, nuclear power, and to capture and sequester the carbon dioxide emitted from our power plants,” Chu said. “Advanced biofuels and the electrification of personal vehicles will make us less dependent on foreign oil.”

Despite his stated optimism, Chu stressed the immediate need for action and the consequences if none is taken. Current climate models indicate that without steps to curb carbon dioxide emissions, global temperatures have a 50 percent chance of climbing five degrees Celsius by the end of the century. He referred to past history to illustrate how potentially catastrophic that could be, saying that during the last ice age the world was just six degrees cooler, a difference that resulted in glaciers covering most of Canada and the northern United States.

He also raised concerns that rising temperatures may trigger certain “tipping points” that could accelerate the problem rapidly. One such tipping point could be the melting of the Arctic permafrost, which would lead to the rapid decomposition of organic material held frozen now and, consequently, the rapid release of methane and carbon dioxide.

Action on climate change needs to occur at a time when the developing world is seeking to upgrade its standard of living to more closely mirror the energy-intensive lifestyles in industrialized nations. The United States uses 25 percent of the world’s energy for just 3 percent of its people. The question, Chu said, is whether the welfare of future generations is important enough to people today to take the needed action.

“While I’m worried, I am hopeful we will solve this problem,” Chu said.

U.S. Energy Secretary Steven Chu’s address at Harvard’s Afternoon Exercises