We've heard it all: the world is consuming too much energy, too fast, and at an increasing rate—but how does a society even begin to talk about this global crisis?

Instead of comparing gallons, kilowatts and tons, Ripu Malhotra, PhD, uses an all-encompassing term: a cubic mile of oil (CMO). One CMO is the current total oil consumption the world uses in one year, Malhotra explained in Thursday's Café Scientifique presentation at SRI International in Menlo Park, where he has worked since 1979.

Malhotra aims to reframe the debate about energy. "Part of the problem is,we haven't had a good language to talk about it," said Malhotra, author of the book, A Cubic Mile of Oil.

Picture a large stadium—say, the Oakland Coliseum. Multiply that by 1,000 and you have one cubic mile of oil—a year's worth of energy to power the world. That's about 80 million barrels of oil a day.

When all sources of energy are considered—from natural gas to nuclear, solar and everything inbetween—the world consumes about 3 CMO per year. Researchers predict that demand to increase threefold by 2050, to 9 CMO per year. That is, of course, unless we make a serious change in our energy consuming habits.

If we don't make the necessary changes, scientists like Malhotra have said, we could run out of energy reserves by as early as 2050.

"We have been living off our inheritance, and the question is, how long will our inheritance last?" Malhotra said, addressing an audience of primarily well-informed SRI researchers with furrowed brows.

The concept of a CMO was coined by SRI's Hew Crane in the 1980s while he was waiting in line to buy gasoline. Crane's concept changed the way many thought about the global energy crisis, allowing for uniformity and understanding. It had a sobering effect.

"We could double conservation efforts and work extra hard," to reach an energy consumption rate of 6 CMO per year by 2050, said Malhotra. "We need innovation. Reducing the demand from 9 CMO to 6 CMO requires new technologies and international cooperation."

Malhotra stressed the urgency of the energy crisis, asking each person to consider the inefficiencies in their daily lives—considering that the residential-commercial sector consumes about 50 percent of the primary energy consumed.

Energy saving practices, such as better insulation, efficient lighting and efficient heating, can pay off. Appliances have become increasingly more efficient. But marketing encourages us to use more, to buy bigger refrigerators and more TVs.

"You can have a bigger impact changing your diet than switching your Suburban for a Prius," Malhotra said of going vegetarian, since food—and in particular, meat—accounts for a huge portion of our total energy consumption.

Consider the "low-hanging fruit" that is efficiency and conservation. "Using less energy than we do is the easiest and most economical path," said Malhotra, "but it does not go all the way."

What we need is a total transformation of lifestyles. What about switching to high-density urban living and mass transit, suggests Malhotra. "There are options, but we all need to step up."

In order to make such a large-scale transformation, however, alternative options for energy production must be considered.

Malhotra explained how much alternative energy would be needed to produce 1 CMO of energy per year by the year 2050 as follows:

• For hydro power, 200 dams would need to be built. That's 2 dams every quarter for 50 years.
• Nuclear power: 2,500 plants. That's one new reactor every Monday for 50 years."
• Concentrated solar power: 7,700 solar parks. That's 3 a week for 50 years.
• Windmills: 3 million. 1,200 a week for 50 years.
• Solar roofs: 4.2 million, or 250,000 roofs a day for 50 years.

But to rely on any one resource is illogical. "We need nuclear and solar and wind...it's going to take them all," said Malhotra. "These goals aren't insurmounatlble, but we've got to face them."

During the Q&A that followed Malhotra's presentation, one audience member proposed another "low-hanging fruit" that hadn't been mentioned—"...access to family planning, giving women the opportunity to plan their families," and in turn prevent population overgrowth.

Other audience members nodded their heads in agreement and applauded. Preventing population overgrowth is yet another path to limiting the world's energy consumption. "The best way to prevent population growth is to improve the standard of living," said Malhotra, who had stated that two-thirds of the people in the world are deprived of an adequate supply of energy. Of course, North America remains the highest consumer of energy, consuming more than it produces.

"It's urgent" that we find solutions and make major transformation, said Malhotra, "because we are already late."

For more information on energy consumption and the Café Scientifique series, visit Sri.com/energy.