Can the energy of the sun be stored in molten glass, supercritical fluids, or metal? Can genetic engineering squeeze more biofuel from pine trees or tobacco? Can new alloys be created to replace the rare earth minerals so important to alternative energy?

These are among 60 research projects named Thursday to share in $156 million in U.S. government grants to push the cutting edge of energy technology. It is the fourth round of funding in the U.S. Department of Energy’s two-year-old ARPA-E (Advanced Research Projects Agency-Energy) program, an effort to inject support into “high-risk, high-payoff” research on energy.

ARPA-E is modeled after DARPA, the Pentagon’s long-running program to support innovative military systems research, which is credited with the advances in computing networking that paved the way for the Internet. Energy Secretary Steven Chu, long before he took office, was among a vanguard of scientists who urged a similar concerted research program to spur advances in energy technology.

Seed Money and Plant Fuel

Each of the 60 new grantees is receiving an average of $2 million to $3 million, although a few biofuels grants are for more than $5.5 million. But the point of the federal funds and vote of confidence is to spur more private investment in the needed research. ARPA-E Director Arun Majumdar said in a call with reporters that 11 previous projects that received $40 million in ARPA-E grants have since secured as much as $200 million in pr­ivate investment.

Among the biofuel grantees in the new funding round was the Donald Danforth Plant Science Center in St. Louis, Missouri. It landed about $5.52 million to genetically engineer a variety of the crop camelina that would produce more oil per acre for fuel.

A Chicago-based company called Chromatin secured nearly $5.77 million to lead efforts to engineer sugar-rich sweet sorghum so that the plants will produce more farsenene, which can be converted into a type of diesel fuel.

And the University of Florida scored the largest grant, for nearly $6.37 million, for research efforts focused on pine trees, which naturally produce the liquid biofuel turpentine. With support from ARPA-E, the researchers hope to develop pine trees that can produce and store vastly more turpentine, to the point where less than 25,000 acres (10,117 hectares) of forest could supply turpentine for 100 million gallons (378 million liters) of fuel per year.

Universities will lead half of the projects in this latest round, while small businesses will head up nearly a quarter. National labs, nonprofits, and large businesses like General Electric will lead the rest.

A total of $31.6 million will go toward projects focused on early-stage development of alternatives to rare earth elements, which are used in a wide range of high-tech products, including computers, military gear, wind turbines, and hybrid car batteries.

As much as 90 percent of the world’s supply of these metals currently comes from China. And although mines in California and Australia are expected to begin producing rare earths within the next few years, and geologists have identified large deposits of the elements in southern Afghanistan, China’s recent moves to limit exports of the metals has created a sense of urgency around the kind of projects being backed by ARPA-E—a manganese-based replacement for rare earth magnets used in wind turbines and electric vehicles, for example.

“Rising rare earth prices have already escalated costs for some energy technologies and may jeopardize the availability and widespread adoption of many critical energy solutions by U.S. manufacturers,” the agency said in a press release issued Thursday.

In Search of Storage

The largest portion of new funds ($37.3 million) announced will go toward development of low-cost thermal storage. Of course, using heat to generate electricity or mechanical power is hardly new: Cogeneration, or combined heat and power, systems accounted in 2008 for more than half of total national power production in Denmark, nearly 40 percent in Finland and more than 30 percent in Russia—compared to only 9 percent in the United States, according to a report from the Oak Ridge National Laboratory. (pdf)

But the ARPA-E projects are meant to take leaps in the realm of storage and transfer of heat for solar power, nuclear energy, and electric vehicles. A team led by the University of Utah, for example, will focus on a “hot and cold battery” that, if successful, would provide climate control for electric vehicles without draining the electric battery. And a project led by the University of South Florida would cut thermal energy storage system costs by as much as 75 percent if it succeeds in developing a new kind of so-called “phase-change” materials to transfer heat. These materials take advantage of the energy transfer that occurs when a material changes phases, as when ice changes from solid to liquid.

The company NAVITASMAX of Chandler, Arizona, will receive an $800,000 grant for a one-year proof-of-concept program aimed at creating fluids with extremely high heat capacity to provide low-cost storage of energy at concentrating solar or nuclear power plants. Halotechnics, of Emeryville, California, is receiving $3.3 million for its research into low melting-point molten glass as an energy storage medium.

Abengoa Solar, the Lakewood, Colorado-based division of Spanish company Abengoa, received $3.6 million to develop a high-efficiency solar-electric conversion tower. Coupled with new thermal energy storage, it aims to reduce the cost of concentrating solar power systems by 30 percent.

The latest grants come at a time of uncertainty for ARPA-E. Although President Obama has requested an expanded $505 million budget for the program in the 2012 fiscal year, Thursday’s awards mark the end of funds appropriated to the program by Congress for the 2011 fiscal year. While budget knives are out in some quarters of Capitol Hill for energy programs in the wake of federally supported solar innovator Solyndra’s bankruptcy, others say programs like ARPA-E are woefully underfunded. The Breakthrough Institute, a nonprofit advocacy organization, has argued that the agency should be funded at $1.5 billion annually as part of a massive U.S. government funding commitment needed in clean energy research.