Tuesday, February 3, 2015

Christiane Feldmann-Leben on the Whys and Hows of Hydrogen Fuel Cells

By Kate Forster

At ATA conferences I like to divide my time between sightseeing and professional activities, and among the latter I usually try to take in a wide variety of sessions organized by different divisions. In Chicago in 2014, I found myself attending a lot of Science & Technology Division events (although I’m not a division member or even an ATA member) because the lineup was so strong.

Among the S&TD offerings were two presentations by Distinguished Speaker Christiane Feldmann-Leben, who has a PhD in chemistry and is a freelance translator specializing in chemistry, materials science, pharmacy, and medicine. I had missed her first one while visiting the Field Museum of Natural History, so I was looking forward to the second, “From Oil Economy to Hydrogen Economy: An Introduction to Fuel Cells.”

I don’t have a background in chemistry or engineering, and all I knew about fuel cells (FCs) going in was that they are an alternative energy technology that could be good for the planet. But that was enough to pique my interest, and it was Dr. Feldmann-Leben’s starting point. She outlined why our economy’s current reliance on oil (for example, in the transportation, heating, clothing, and food industries) is problematic: extracting, transporting and burning fossil fuels creates CO2 emissions, which are increasing drastically and are a major component of greenhouse gases that contribute to climate change. Those activities also cause other forms of environmental pollution. And global oil reserves are diminishing, even as our demand for energy continues to increase.

What can we do about it? That’s actually not a new question. I was surprised to learn that, in the late 19th and early 20th centuries, scientists and other thinkers including Jules Verne, Giacomo Luigi Ciamician and J.B.S. Haldane were already envisioning a move away from fossil fuel to cleaner energy based on water, solar power or wind. Nor are fuel cells a new technology—one using sulfuric acid was invented in 1839, and other versions have appeared sporadically over the years. Their first major practical application was as an energy supply on space missions in the 1960s. The oil crisis of the early 1970s spurred researchers to work on developing fuel cells for more widespread use.

The technical portion of Dr. Feldmann-Leben’s presentation contained a wealth of information—far more than I have the space or expertise to summarize adequately. She outlined the basics of electrons and electrical energy; photosynthesis; electrolysis; the hydrogen cycle; hydrogen storage; and, of course, what hydrogen and fuel cells are and what they do. A fuel cell is not a storage device, but “a galvanic element converting chemical into electrical energy,” in contrast to an internal combustion engine, which converts chemical energy into thermal/mechanical energy. Hydrogen, the most abundant chemical substance in the universe, is a colorless and highly combustible gas occurring mostly in molecular form (water and organic molecules). It is produced by splitting water (H2O) molecules into hydrogen (H2) and oxygen (O2) gases and can be stored in several forms. Dr. Feldmann-Leben then described the basic components of a fuel cell, how FCs work, and their energy-conversion efficiency.

An impressive array of fuel cells already exists. They are being used for many different purposes, including military and space applications; backup and portable power; transportation (for example, fuel-cell-powered buses in California); consumer electronics such as laptops and cellphones; and electrical power plants, distributed generation and auxiliary power. There’s even a small-scale generator (the BlueGen) designed for home use, powered by a fuel cell. Recently, a new hydrogen-producing process that mimics photosynthesis was developed, using solar cells that act like artificial leaves. In October 2014, the efficiency of this process was improved to 13%—a possible breakthrough. New FCs currently under development include enzymatic biofuel cells for “in-body” applications and microbial fuel cells for producing energy in sewage treatment plants.

The major challenges now facing fuel-cell researchers are to reduce the cost of materials, increase the lifetime of FCs, find ways to store hydrogen more efficiently, and produce hydrogen directly from sunlight.

Even without absorbing all the technical details of the presentation, I gained a better understanding of the economic and environmental importance of fuel-cell technology. The previous day, I had stood before the last exhibit in the Field Museum’s Hall of Evolution: a counter showing the number of species that have gone extinct since 8:00 a.m. each day. At 12:53 p.m. on November 6, 2014, the number was 17. That represents an estimated 30,000 extinctions per year, most of them attributable to human activity, so our current extinction crisis was on my mind during the presentation. Now that the oil economy has brought us to this point, could transitioning to a hydrogen economy help us live more sustainably? Dr. Feldmann-Leben ended with a very positive statement on fuel cells’ possibilities: “This technology is on the verge of changing the world.”

Kate Forster is a French-to-English translator based in Montreal. Her focus is biology and the environment.

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