Renewable energy is getting cheaper and cheaper. Perhaps within this decade, wind and solar will be as inexpensive as any form of new energy. Wind is now pegged at 7.2 to 7.5 cents per kilowatt-hour at a levelized cost of energy according to Bloomberg New Energy Finance. [A leveled cost of energy is a measure of all the costs of a given energy source, from construction to fuel costs.] Natural gas is about 6 cents. A new coal plant is actually more money. Levelized wind is cheaper than coal.
Solar is more expensive; it's twice as expensive. We believe it will come down twofold in the next decade. It's already come down threefold in the last four years. We see the electricity mix going to less and less carbon.
Where do you think such breakthroughs might come from?
Breakthroughs on the physics side will be in materials. The battery manufacturer Envia, which both [the U.S. Department of Energy's (DoE) Office of Energy Efficiency and Renewable Energy and its Advanced Research Projects Agency–Energy] supported just announced a 400-kilowatt-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 bulletproofing, testing. It will reduce the cost of batteries at least twofold and the company is a little more optimistic—they think fourfold.
We are investing in other battery companies that will go another factor of two beyond that. If we see those types of batteries, once you're down to around $150 to $200 per kilogram within a decade, which is the DoE goal, then you have $20,000 to $25,000 cars going 150 miles that will pay for themselves in five years with lower fuel costs. That compares to $18,000 for a regular five-passenger car. It's not a $50,000 to $100,000 car; it's something all Americans can afford. If we get those prices, that will occur—though I don't know how long it will be before we get that. The feeling of driving past a gas station forever is priceless.
Biofuels are a little bit further out only because your competition is oil. We would like to develop an industry without any subsidies whatsoever and with very low other carbon inputs so you get a five-to-one reduction in the amount of CO2. Early-stage research sponsored by DoE has microbes where you feed it simple sugars and out pops diesel fuel. It's been piloted in Brazil because sugar is inexpensive there but they are looking for a plant in the U.S. to use corn starches instead. Ultimately, their goal is to feed it complex sugars like cellulose and hemicellulose and out pops diesel, gasoline or jet fuel.
Another company is using photosynthetic bacteria and swapping whole genomes and metabolic pathways. It generates long alkane chains that are the immediate precursors to diesel fuel. It's 5 to 10 percent energy efficient where a typical plant is only 1 percent efficient. Eighty percent of the metabolism of this poor cyanobacteria has to be generating fuel. It's already worked. Now we have to get the metabolism up further and many synthetic biologists feel they can do that. They know how to ratchet down metabolic energy used in things like reproduction. They want to just keep those systems alive that do self-repair and make the fuel. This is a little weird bacteria or yeast. In the last 15 years or so, I've gotten into biology like this. I follow this with avid interest. It's really almost science fiction.