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Energy Secretary Steven Chu Discusses the "Weird Little Bacteria" in Our Energy Future

Steven Chu on the futuristic batteries and "little weird" bacteria that will pave our way to energy independence



Imke Lass/Redux Pictures

Name: Steven Chu
Title: U.S. Secretary of Energy
Location: Washington, D.C.

Is domestic energy indepen­dence a useful goal?
It’s certainly a useful goal to strive toward energy indepen­dence. The good news is that three and a half years ago we were importing about 60 percent of our oil, and now it’s around 45 percent. We see the trend going for­ward, decreasing even more. We are already largely energy-independent in terms of electricity generation, although some electricity comes from Canada.

We also see a flattening, perhaps even a decrease, in the use of transportation fuels as we go to more efficient automobiles. We see more diversification of transportation energy. Liquefied natural gas for long-haul trucks has already been shown to make sense. Private companies are investing hundreds of millions of dollars to build natural gas infrastructure. If you build it every 200 miles on the highway, you can capture a significant market, perhaps even half the market, and heavy trucks consume 20 percent of our transportation energy.

Does that mean we’ve given up on combating climate change?
No, absolutely not. This is all very consistent with climate change. Natural gas as a transition fuel is great. It’s half the [carbon dioxide of burning coal]. We still need to figure out how to capture its carbon, which we need by midcentury no matter what the large source is [whether it is coal, oil or natural gas].

Renewable energy is getting cheaper and cheaper. Perhaps within this decade wind and solar will be as inexpensive as any form of new energy. Solar has already come down threefold in the past four years, and we believe it will come down twofold in the next decade.

In transportation, there will be a mix of electrification and next-generation biofuels and efficiency. If we get breakthroughs, it can be game-changing.

Where do you think such break­throughs might come from?
Breakthroughs on the physics side will be in materials. The battery manufacturer Envia [Systems] announced a 400-watt-hour-per-kilogram battery. That’s at least a factor of two more than the previous best. It still has to go through some more stages of testing. We are investi­ng in other battery companies that will go another factor of two beyond that.

Biofuels are a little bit further out only because your competition is oil. Early-stage research sponsored by the Depart­ment of Energy has microbes you can feed simple sugars and out pops diesel fuel. Another company is using photo­synthetic bacteria and swapping whole genomes and metabolic pathways. [The microbe] generates long alkane chains that are the immediate precursors to diesel fuel. It’s 5 to 10 percent energy-efficient, whereas a typical plant is only 1 percent efficient. This is a little weird bacterium or yeast. In the past 15 years or so I’ve gotten into biology like this. I follow it with avid interest. It’s really almost science fiction.

What have you learned about how the government should fund new energy companies?
In areas of rapidly moving technology, you have to be increasingly careful when assisting in deployment. Some things happened so rapidly that nobody anticipated them. For example, the price of photovoltaics dropped 80 percent in [recent years] and 40 percent in another year. Those prices have now stabilized.

It’s very important that the U.S. remain a player in this technology [photovoltaics]. We invented a lot of this stuff [such as modern solar cells]—you name it. We still have the capability of outcompeting.

I knew full well coming in that unex­pected things can happen. [Tech­nology] leads can be lost. It’s a very competitive world out there. For example, we invented the airplane, lost the lead, then came back.

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