Energy issues are of paramount concern to our nation’s economic stability and national security. First, there is a growing acknowledgement that the United States must diversify our energy portfolio to be less dependent on volatile oil markets controlled by unstable governments. Moreover, the need for carbon dioxide mitigation is becoming more urgent as the world continues to experience the effects of global warming.
Hydrogen Research and Development
Sandia researcher Daniel Dedrick handles a complex metal hydride within an inert production and storage environment. Complex metal hydrides, along with many hydrogen storage materials, react readily when exposed to air and moisture. A Sandia-led project was initiated to quantify the reactivity of these materials to enable their safe production, handling, storage, and use in automotive applications.
Sandia is advancing the use of hydrogen as an energy carrier through a range of research and engineering projects that can help diversify our country’s energy portfolio while simultaneously decreasing harmful greenhouse emissions. Our work, which is aligned with the national directive to develop commercially viable hydrogen-powered vehicles, is an important part of the Department of Energy’s (DOE’s) efforts to move the United States toward a new hydrogen-based energy economy
Projects in Sandia’s Hydrogen Program range from fundamental research on hydrogen properties to comprehensive systems engineering of hydrogen technologies. Sandia scientists and management are also responsible for providing technical program guidance to DOE in areas such as hydrogen storage and materials research; safety, codes, and standards; infrastructure; distributed power; reacting flows; and systems analysis.
Sandia’s Hydrogen Program spans a breadth of technical activities, including the following:
- Research and development of sensors; hydrogen storage in complex metal hydrides; hydrogen production from fossil fuels, nuclear energy, and renewable energy sources; hydrogen-fueled internal combustion reciprocating engines; and advanced combustion capabilities for hydrogen and hydrogen-blended hydrocarbon fuels in gas turbines.
- Developing materials for hydrogen separation, advanced materials for fuel cell membranes, and new materials to improve electrolysis.
- Modeling fuel cell systems.
- Integrating the various hydrogen technologies subsystems.
- Using systems modeling to analyze alternative hydrogen futures.
- Developing science-based codes and standards to ensure hydrogen safety.
For more information, contact Don Hardesty at (925) 294-2321 or Jay Keller at (925) 294-3316.
Biofuels
The biofuel life cycle — from feedstock to end user. (Source: DOE)
The dependence of the United States on imported foreign energy supplies, specifically petroleum and petroleum-based derivatives, has become a national-security issue. Imports of petroleum are expected to grow because of the continual rise in global demand and decline in domestic oil production. The transportation sector depends almost entirely on petroleum fuels to meet current energy demands and consumes approximately 200 billion gallons of nonrenewable petroleum-based products (gasoline and diesel) each year. This dependence on imports, the recent turbulence in gasoline prices, the threat of diminished overall petroleum supplies, and shortages in refining capacities all provide impetus to research alternative, renewable fuels derived from biomass. In short, it is important to find a national approach to transportation fuel generation that produces a diverse range of feedstock options with a robust, economical, and efficient system of availability and distribution.
According to the DOE, the total addressable U.S. hydrocarbon market, which could potentially be substituted by biobased products, is significant — 540 million tons per year. Demand between now and 2050 includes two segments: (1) replacement markets for petrochemicals and (2) the remaining increase in overall global demand for fuels, power, and products. The DOE has established an aggressive timeline for the overall production of biofuels from biomass, thereby displacing a significant portion of fuels derived from fossil fuel sources.
The transition of biofuel production from current niche levels to a level with a significant market share in the transportation fuel sector requires numerous significant advances in both science and technology. Sandia researchers at both the California and New Mexico laboratories are poised to play a critical role in the advancement of biofuels for the nation. Building on the success of the Combustion Research Facility, Sandia/California will expand current research programs in bioscience, thermochemistry, biochemistry, microsystems, computational science, and advanced chemical imaging to meet the goals set forth by the nation.
Current biofuels projects at Sandia/California include the following:
- The Joint BioEnergy Institute (JBEI) is a $125 million project funded by the DOE Office of Science to develop science-based innovations for converting biomass to biofuels. JBEI will combine the resources and personnel of six partner institutions: Lawrence Berkeley National Laboratory; Sandia National Laboratories; Lawrence Livermore National Laboratory; University of California (UC), Berkeley; UC Davis; and Stanford University. JBEI participants from Sandia/California will use their unique resources and skills in computing, bioscience, high-throughput microsystems, and advanced chemical imaging instruments to meet the scientific milestones of this project.
- The Combustion Research Facility was awarded $1.2 million by the Department of Energy to establish an internal combustion engine that runs on ethanol and ethanol/gasoline blends. This diagnostic engine will be used to study the fundamental combustion characteristics of these ethanol and ethanol/gasoline blends.
- Sandia researchers are engineering enzymes that were isolated from some of Earth’s harshest environments. These enzymes, which can convert biomass into fermentable sugars at high temperatures and extreme pH levels, are ideally suited for industrial settings that use such temperatures and pH variations. The enzymes also offer a potential path toward consolidated bioprocessing.
- Researchers are developing new strains of algae to serve as a potential biomass feedstock for the production of biofuels such as biodiesel and ethanol. These discoveries are coupled to enhanced extraction and conversion technologies that will decrease the overall cost of producing fuels from algae. Algae are one of the most promising sources of biomass because they do not compete with traditional agricultural systems designated for food or grain production, can be grown using impaired waters, and can be grown to high levels in certain environments.
- An engineered thermophilic bacterium under development at Sandia/California can simultaneously ferment pentose and hexose sugars into ethanol. Using bacteria to ferment sugars at high temperatures (>60°C) has several distinct advantages. First, bacteria can ferment a wider range of sugars than yeast. Next, the risk of accidental contamination by other microorganisms is lower, a critical element in the aseptic operation of large-scale, commercial fermentation facilities. In addition, because of ethanol’s high vapor pressure, the fermentor and the distillation system can be integrated, thereby enabling the continuous removal of ethanol from the culture and facilitating product recovery. Finally, the bacterial fermentation process is compatible with cellulosic biomass pretreatment methods.
Sandia’s hyperspectral fluorescence imaging system can distinguish between hundreds of dyes used to image biomass, as shown by these cross-sectional images of a corn leaf sample using (a) hyperspectral fluorescence and (b) a commercial filter. (BS = bundle sheath; M = mesophyll; E = epidermis)
- In nature, several different organisms operate in concert to convert biomass into energy. Researchers are investigating some of these microbial communities in a laboratory environment to identify, isolate, and manipulate the systems that are the critical links in this conversion system.
- The hyperspectral fluorescence imaging system, a unique analytical tool developed at Sandia, can distinguish between the hundreds of different fluorescent dyes used to image biomass. Researchers at Sandia are collaborating with Monsanto to further develop this tool for biomass analysis applications that will make significant contributions to the to the development of corn hybrids that offer more ethanol output per bushel.
Computational model of cellulase enzyme structures. These structural comparisons are used to predict which mutations will enhance the hydrolysis of cellulose into glucose. (Source: Diana Roe)
- Sandia is working to optimize the design of future lignocellulosic biomass biorefineries. Researchers are performing experimental measurements and system modeling to investigate the relationships between biomass type, the type of pretreatment process used to prepare the biomass for subsequent biochemical production of ethanol, and the suitability of the lignin residue material (which can’t be biochemically converted to ethanol) to be gasified for additional liquid-fuel production.
- Producing enzymes at a biorefinery is currently one of the most costly process steps associated with converting cellulose into ethanol. Sandia is investigating the expression of cellulolytic enzymes within plant feedstock. These enzymes, which start the hydrolytic degradation of cellulose, could then be activated by an external trigger. The enzymes are inactive at room temperature and would not pose any risk to a plant’s structural integrity during growth, harvest, or storage. Producing enzymes within the biomass itself would represent a significant advance in the cellulosic ethanol effort.
For more information, contact Blake Simmons at (925) 294-2288 or Katherine Andrews at (505) 844-4775.