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Biofuels Aren’t Really Green

Cultivate inorganic energy sources instead of biofuels

7 min read
Photo by Dan Saelinger; Styling: Lauren Shields
Photo: Dan Saelinger; Styling: Lauren Shields

Sustainable, green, renewable, organic—the words come up so often in energy and climate debates that they tend to sound as if they mean the same thing. But of course they don't. Nuclear reactors emit no carbon and are therefore in a sense green, but uranium is nonrenewable; hydropower is green and renewable but may not always be sustainable, because the ecological consequences can be bad and reservoirs are not limitless; coal is organic, but its carbon emissions make it the very opposite of green. All that is obvious enough. But even so, it may be jarring to hear—as we have found and will describe—that organic biofuels can't possibly fuel a growing world economy in a sustainable manner, whereas, in principle, inorganic fuels could.

That inorganic might beat organic contradicts fashionable prejudice, which like all fashion changes with the season. Take the case of the United States: First came the enthusiasm for corn ethanol, its extravagant subsidization, and a farm-industrial miniboom. Then, when corn's limits started to become better known and its costs more glaringly obvious, we started to hear about the promise of switchgrass, a native species of the North American prairie that promises high energy-conversion efficiencies. President George W. Bush first mentioned it in a 2006 speech to the nation. Before long, Al Gore was chiming in too, promising that with adequate government support for research, grass-based fuels could free us from the dual specters of energy shortage and runaway climate change.

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Paying Tribute to 1997 IEEE President Charles K. Alexander

The Life Fellow was a professor at Cleveland State University

4 min read
portrait of man smiling against a light background
The Alexander Family

Charles K. Alexander, 1997 IEEE president, died on 17 October at the age of 79.

The active volunteer held many high-level positions throughout the organization, including 1991–1992 IEEE Region 2 director. He was also the 1993 vice president of the IEEE United States Activities Board (now IEEE-USA).

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Robot Learns Human Trick for Not Falling Over

Humanoid limbs are useful for more than just manipulation

3 min read
A black and white humanoid robot with a malfunctioning leg supports itself with one arm against a wall

This article is part of our exclusive IEEE Journal Watch series in partnership with IEEE Xplore.

Humanoid robots are a lot more capable than they used to be, but for most of them, falling over is still borderline catastrophic. Understandably, the focus has been on getting humanoid robots to succeed at things as opposed to getting robots to tolerate (or recover from) failing at things, but sometimes, failure is inevitable because stuff happens that’s outside your control. Earthquakes, accidentally clumsy grad students, tornadoes, deliberately malicious grad students—the list goes on.

When humans lose their balance, the go-to strategy is a highly effective one: use whatever happens to be nearby to keep from falling over. While for humans this approach is instinctive, it’s a hard problem for robots, involving perception, semantic understanding, motion planning, and careful force control, all executed under aggressive time constraints. In a paper published earlier this year in IEEE Robotics and Automation Letters, researchers at Inria in France show some early work getting a TALOS humanoid robot to use a nearby wall to successfully keep itself from taking a tumble.

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Designing Fuel Cell Systems Using System-Level Design

Modeling and simulation in Simulink and Simscape

1 min read
Designing Fuel Cell Systems Using System-Level Design

Design and simulate a fuel cell system for electric mobility. See by example how Simulink® and Simscape™ support multidomain physical modeling and simulation of fuel cell systems including thermal, gas, and liquid systems. Learn how to select levels of modeling fidelities to meet your needs at different development stages.