Our current electrical grid is outdated and inefficient, and a big chunk of the stimulus—about $4.5 billion—is devoted to modernization. For example, the Baltimore Gas and Electric Co. received a $200 million stimulus grant to install smart meters in the homes of roughly 2 million Maryland customers. The idea is that people would be able to watch the price of electricity fluctuate at different times during the day and adjust accordingly, running their dishwashers during off-peak hours, for example, thus saving money and easing the strain on the grid. Down the road, the smarter meters could eventually help consumers choose between dirty and clean sources of electricity or instantly alert the utility company to sources of grid failures, reducing outages. All told, BGE says the devices could reduce electric bills by some $2.6 billion.
Pat Sullivan / AP Photo
At the moment, the country gets less than 1 percent of its electricity from geothermal plants, which extract heat from sources beneath the Earth's surface, such as geysers and hot springs. But "enhanced" geothermal holds greater promise. The idea is to drill some 12,000 feet down into the crust and pump water through the hot bedrock, generating steam. One MIT analysis estimates that there's the potential for at least 100 gigawatts of carbon-free power, equal to 200 coal plants, by 2050. The catch? Drilling that far down is difficult—drill bits tend to get fouled or snap in the hard cap rock. That explains why ARPA-E granted Colorado-based Foro Energy $9.1 million to develop a new hybrid drilling system that would use heat to soften the crystalline rock before drilling through it.
Corn and soy-based ethanol has come in for plenty of derision lately, given evidence that farmers may be hacking down forests to plant crops for fuel. But what if we could get biofuels from a non-food source like algae? Despite a lot of hype, algae fuels are still unproven, but the Energy Department is trying to nudge them forward. Beyond tens of millions of dollars in demonstration funding for private algae-fuel startup companies like Sapphire Energy, ARPA-E is funding long-shot research into even more advanced fuels. There's $9 million for a joint venture between DuPont and Seattle-based Bio Architecture Lab, experimenting with breaking down algae into basic sugars to generate fuel more efficiently. Meanwhile, Arizona State University got $5.2 million for its efforts to engineer cyanobacteria that would require just sunlight, water, and carbon dioxide as inputs, and would secrete fatty acids that could be used as a feedstock for green jet fuel or gasoline.
L: Marcio Jose Sanchez / AP Photo
Although wind power is slowly catching on in the United States (thanks, in large part, to tax credits and renewable-power mandates), the technology is still in its relative infancy. Most of the classic "propeller"-style turbines, for instance, harvest only about half of the wind's potential energy. FloDesign is hoping it can do better. The Massachusetts-based company received $8.3 million in ARPA-E funds to develop a new type of wind turbine that works more like a jet engine: The wind is funneled into a vortex, spinning a smaller set of kitchen fan-like blades. In theory, these turbines would be more than twice as efficient and require less area than conventional turbines (they'd also be less of an eyesore). The catch is that FloDesign hasn't built a large-scale working turbine yet, and further kinks could emerge, although the company has said it will have a small, 10-kilowatt system up and running in 2010.
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If wind and solar are ever going to play more than a niche role in the country's power supply, we'll have to find ways to store their energy during times when the sun's not shining and the wind's not blowing. Batteries are one obvious possibility, but they're still too expensive at the scale needed to store power on the grid (think megawatt-rated battery systems as big as a room), and many experts believe the only way to get there will be to fundamentally revamp battery chemistry. That’s why, in addition to the stimulus' $2 billion in grants for battery manufacturing (much of which will focus on electric-vehicle batteries), ARPA-E is laying down some bets on even more advanced options, like $6.9 million for MIT researchers who are pursuing an all-liquid-metal, grid-scale battery, or $7.2 million for Missouri-based EaglePicher Technologies and Pacific Northwest National Laboratory, which are trying to construct sodium beta alumina batteries that operate at temperatures below the current standard—a sizzling 300°C.
Just minimizing all the waste involved in heating and cooling buildings could reduce U.S. energy use by 12 percent. Better technology could help. Stanford University won $5 million in ARPA-E funds to develop sensors and software that would track energy-use patterns in buildings, making it easier to root out needless waste—say, by adjusting thermostats in rooms that are hardly ever used, or by allowing designers to understand more precisely how different types of insulation or window glass will affect energy use. Similarly, Colorado-based ITN Energy received $5 million from ARPA-E to develop an electrochromic film that could be used to produce cheaper "smart windows," which could fine-tune the amount of light and heat that pass through the glass, potentially leading to very large energy savings.
Chris Gardner / AP Photo
The idea of capturing and sequestering carbon from coal-fired plants may be contentious—critics say it may never work; advocates insist it's the only realistic way to avert global warming—but given the industry's clout in Congress, it's unlikely "clean coal" will be going away anytime soon. Trouble is, capturing carbon from coal plants is still expensive, and a big technological breakthrough wouldn't hurt. So ARPA-E gave Hartford, Connecticut-based United Technologies Research Center $2.2 million to develop synthetic enzymes that would strip the carbon dioxide from a coal plant's flue gas, using a process similar to the one our bodies use to get rid of CO 2. If it pans out—and as with all these technologies, it's a giant "if"—it could dramatically reduce the cost of carbon capture.
