OPEN 2012

The National Renewable Energy Laboratory (NREL) is developing a solar thermoelectric generator to directly convert heat from concentrated sunlight to electricity. Thermoelectric devices can directly convert heat to electricity, yet due to cost and efficiency limitations they have not been viewed as a viable large-scale energy conversion technology. However, new thermoelectric materials have dramatically increased the efficiency of direct heat-to-electricity conversion. NREL is using these innovative materials to develop a new solar thermoelectric generator.

Alveo Energy is developing a grid-scale storage battery using Prussian Blue dye as the active material within the battery. Prussian Blue is most commonly known for its application in blueprint documents, but it can also hold electric charge. Though it provides only modest energy density, Prussian Blue is so readily available and inexpensive that it could provide a cost-effective and sustainable storage solution for years to come.

Case Western Reserve University is developing a water-based, all-iron flow battery for grid-scale energy storage at low cost. Flow batteries store chemical energy in external tanks instead of within the battery container. Using iron provides a low-cost, safe solution for energy storage because iron is both abundant and non-toxic. This design could drastically improve the energy storage capacity of stationary batteries at 10-20% of today’s cost.

Colorado State University (CSU) is developing technology to rapidly introduce novel traits into crops that currently cannot be readily engineered. Presently, a limited number of crops can be engineered, and the processes are not standardized – restricting the agricultural sources for engineered biofuel production. More—and more diverse—biofuel crops could substantially improve the efficiency, time scale, and geographic range of biofuel production.

Ceramatec is developing a small-scale reactor to convert natural gas into benzene—a feedstock for industrial chemicals or liquid fuels. Natural gas as a byproduct is highly abundant, readily available, and inexpensive. Ceramatec’s reactor will use a one-step chemical conversion process to convert natural gas into benzene. This one-step process is highly efficient and prevents the build-up of solid residue that can occur when gas is processed. The benzene that is produced can be used as a starting material for nylons, polycarbonates, polystyrene, epoxy resins, and as a component of gasoline.

Georgia Tech Research Corporation is developing a supercapacitor using graphene—a two-dimensional sheet of carbon atoms—to substantially store more energy than current technologies. Supercapacitors store energy in a different manner than batteries, which enables them to charge and discharge much more rapidly. The Georgia Tech team approach is to improve the internal structure of graphene sheets with ‘molecular spacers,’ in order to store more energy at lower cost.

The University of Washington (UW) is developing technologies for microbes to convert methane found in natural gas into liquid diesel fuel. Specifically the project seeks to significantly increase the amount of lipids produced by the microbe, and to develop novel catalytic technology to directly convert these lipids to liquid fuel. These engineered microbes could enable small-scale methane-to-liquid conversion at lower cost than conventional methods. Small-scale, microbe-based conversion would leverage abundant, domestic natural gas resources and reduce U.S. dependence on foreign oil.

The California Institute of Technology (Caltech) is developing a solar module that splits sunlight into individual color bands to improve the efficiency of solar electricity generation. For PV to maintain momentum in the marketplace, the energy conversion efficiency must increase significantly to result in reduced power generation costs. Most conventional PV modules provide 15-20% energy conversion efficiency because their materials respond efficiently to only a narrow band of color in the sun’s spectrum, which represents a significant constraint on their efficiency.

Georgia Tech Research Corporation is developing a high-efficiency concentrating solar receiver and reactor for the production of solar fuels. The team will develop a system that uses liquid metal to capture and transport heat at much higher temperatures compared to state-of-the-art concentrating solar power facilities. This high temperature system will be combined with the team’s novel reactor to produce solar fuels that allow the flexibility to store and transport solar energy for later use or for immediate power production.

Vorbeck Materials is developing a low-cost, fast-charging storage battery for hybrid vehicles. The battery cells are based on lithium-sulfur (Li-S) chemistries, which have a greater energy density compared to today’s Li-Ion batteries. Vorbeck’s approach involves developing a Li-S battery with radically different design for both cathode and anode. The technology has the potential to capture more energy, increasing the efficiency of hybrid vehicles by up to 20% while reducing cost and greenhouse gas emissions.