op-ed

Why everything wants more power

Adrian Bejan & J. Peder Zane Authors, Design in Nature
Font Size:

Rising gas prices and turmoil in the Middle East have once again thrust energy issues to the center of the presidential campaign.

As usual, the incumbent is being blamed for failing to ease our pain at the pump. But this time around there’s a new twist in the script. Instead of vowing to lower prices, President Obama is noting that we have little control over the price of energy in a thirsty global market.

Between 1971 and 2009 per capita energy consumption around the world grew by 34 percent, according to the World Bank. It grew another 5.6 percent in 2010; projections only see this upward trend continuing.

By viewing energy in a world context, we’re adding some much-needed reason to the debate. But that does not go far enough. The economic growth of India, China and other developing countries is only a symptom, not a root cause, of the surging demand for energy. A more fundamental dynamic is at work. To take a truly global view of energy we must look past politics to physics — yes, physics.

Widening our lens to include not only human activity but also the natural world, we make a startling discovery: everything around us is doing exactly what we are, using more power to move more mass more easily on the landscape. This is not the result of accident or choice but a manifestation of a universal law — as powerful as the laws of motion and thermodynamics — that has shaped our world, and our selves. It tells us why, despite growing fears of global warming, increased calls for conservation and technological breakthroughs that have increased efficiency, we continue to use more and more power.

Energy is commonly thought of as a resource used only by people. In fact, everything that moves requires power because to move means to be driven by power.

Rivers, wind currents and forests need power just as surely as cars and factories. Like us, these natural phenomena derive almost all their power from the sun. Indeed, the entire Earth is a flowing tapestry of currents — people, birds, weather patterns, etc. — that move mass from here to there.

None of these things just fell from the sky fully formed. All have evolved with a single direction in time, using more power to move more easily. This fact is obvious in human history. From the first foot paths and the invention of the wheel, to the continuing industrial revolution which has given us trains, planes, cell phones and iPads, we have used more and more power to move ourselves and our things faster, farther and more efficiently.

Surprisingly, we find the same pattern in the history of the natural world. Imagine, for example, the first raindrops that fell upon the earth. Initially, they landed and seeped through the ground. Seeping is not an easy way to move. Over time, raindrops coalesced, using more power to carve out rivulets, brooks and large channels such as the Mississippi and the Danube that allowed them to move more water faster and farther. These channels and the area they serve are the “design” of the river basins that cover the globe.

Why — and how — did these mindless splashes of water merge to create these intricate and predictable patterns we find today? The answer is the universal tendency of everything that moves to use power to create designs to move more easily. This same phenomenon occurs across the board, generating the evolving shape and structure of everything from vegetation and animals to technology, cities and air transport networks. All have evolved with a single direction in time: using more and more power to generate better and better flow configurations (or designs). Better means moving more current — whether it’s water, electricity or body mass — per unit of useful energy (fuel) consumed. Which is to say, more efficiently.

In the 16 years since I discovered this principle — the Constructal Law of design in nature — researchers around the world have not found a single phenomenon that violates it.

The projection of increasing world energy use, then, is correct not as a question of politics, but of physics. As we are part of nature, we are governed by the same tendency, the same powerful urge, as all around us. Some might complain that this leaves no room for free will, that we have no more choice than a raindrop. The response to this is clear: whatever we would like to believe, natural and human history tell a consistent story. Each of us could decide, on our own, to reduce our use of power, but accomplishing this on a global scale would be impossible. The fault lies not in our politics, but in our nature. To confront our energy needs we must take a truly global view which begins by recognizing that everyone and everything wants more power.

Adrian Bejan, the J.A. Jones Distinguished Professor of Mechanical Engineering at Duke University, and J. Peder Zane, an assistant professor of journalism at St. Augustine’s College, are the authors of “Design in Nature: How the Constructal Law Governs Evolution in Biology, Physics, Technology, and Social Organization” (Doubleday).