Today many biofuel refineries operate for only seven months each year, turning freshly harvested crops into ethanol and biodiesel. When supplies run out, biorefineries shut down for the other five months. However, according to recent research, dual-purpose biofuel crops could produce both ethanol and biodiesel for nine months of the year—increasing profits by as much as 30%.
“Currently, sugarcane and sweet sorghum produce sugar that may be converted to ethanol,” said co-lead author Stephen Long, Gutgsell Endowed Professor of Plant Biology and Crop Sciences at the Carl R. Woese Institute for Genomic Biology at the University of Illinois. “Our goal is to alter the plants’ metabolism so that it converts this sugar in the stem to oil—raising the levels in current cultivars from 0.05% oil, not enough to convert to biodiesel, to the theoretical maximum of 20% oil. With 20% oil, the plant’s sugar stores used for ethanol production would be replaced with more valuable and energy dense oil used to produce biodiesel or jet fuel.”
A paper published in Industrial Biotechnology simulated the profitability of Plants Engineered to Replace Oil in Sugarcane and Sweet Sorghum (PETROSS) with 0%, 5%, 10%, and 20% oil. They found that growing sorghum in addition to sugarcane could keep biorefineries running for an additional two months, increasing production and revenue by 20-30%.
Today, PETROSS sugarcane produces 13% oil by dry weight, 8% of which is the kind of oil used to make biodiesel. At 20% oil, sugarcane would produce 13 times more oil—and six times more profit—per acre than soybeans.
A biorefinery plant processing PETROSS sugarcane with 20% oil would have a 24% international rate of return—a metric used to measure the profitability of potential investments—which increases to 29% when PETROSS sorghum with 20% oil is processed for an additional two months during the sugarcane offseason.
“When a sugarcane plant has to shut down, the company is still paying for capital utilization; they have spent millions of dollars on equipment that isn’t used for five months,” said co-lead author Vijay Singh, Director of the Integrated Bioprocessing Research Laboratory at Illinois. “We propose bringing in another crop, sweet sorghum, to put that equipment to use and decrease capital utilization costs.”
By decreasing capital utilization costs, the cost to produce ethanol and biodiesel drops by several cents per liter. Processing lipid-sorghum during the lipid-cane off-season increased annual biofuel production by 20 to 30%, thereby increasing total revenue without any additional investment in equipment.
The simulations in this paper accounted for the equipment required to retrofit ethanol plants to produce biodiesel. In the U.S., about 90 percent of ethanol plants are already retrofitted to produce biodiesel. According to Singh, in places like Brazil where they produce a large amount of sugarcane, it makes sense to retrofit ethanol plants. “Our study shows that it is cost effective to do it.”
In contradicting a theory that’s been the standard for over eighty years, an Illinois group led by Yang Zhang, assistant professor of Nuclear, Plasma, and Radiological Engineering and Beckman Institute for Advanced Science and Technology, has made a discovery holding major promise for the petroleum industry.
The research has revealed that in the foreseeable future products such as crude oil and gasoline could be transported across country 30 times faster, and the several minutes it takes to fill a tank of gas could be reduced to mere seconds.
Over the past year, using high flux neutron sources at the National Institute of Standards and Technology (NIST) and Oak Ridge National Laboratory (ORNL), Zhang’s group has been able to videotape the molecular movement of alkanes, the major component of petroleum and natural gas. The group has learned that the thickness of liquid alkanes can be significantly reduced, allowing for a marked increase in the substance’s rate of flow.
“Alkane is basically a chain of carbon atoms,” Zhang said. “By changing one carbon atom in the backbone of an alkane molecule, we can make it flow 30 times faster.”
The discovery of Zhang, his graduate students Ke Yang, Zhikun Cai, and Abhishek Jaiswal, and collaborators Dr. Madhusudan Tyagi at NIST and Jeffrey S. Moore, Interim Director of the Beckman Institute and HHMI Professor of Chemistry at Illinois, disproves a well-known theory that Princeton University Profs. Walter Kauzmann and Henry Eyring formed in the late 1940s. They had predicted that all alkanes have a universal viscosity near their melting points. Zhang said the theory had been cited over 3,000 times.
However, a rather distinct odd-even effect of the liquid alkane dynamics was discovered. The odd-even effect in solid alkanes is taught in almost every introductory organic chemistry textbook, i.e., the difference in the periodic packing of odd- and even-numbered alkane solids results in odd-even variation of their densities and melting points. However, the same effect was not expected in liquid alkanes because of the lack of periodic structures in liquids.
“We would have thought that no structural memory may carry over from the solids to the liquids,” Prof. Martin Gruebele, the James R. Eiszner Chair Professor in Chemistry, said, “but clearly, the cooler liquid already has the origins of the odd-even effect built into its diffusion!”
“The classical Kauzmann-Eyring theory of molecular viscous flow is over simplified,” Zhang said. “It seems some chemistry textbooks may need revisions.”
The Illinois scientists had the technological advantage of super high-speed (at the pico-second, 1 trillionth of a second) and super high-resolution (at the nano-meter, 1 billionth of a meter) “video cameras” making use of neutrons to take movies of the molecules. “A neutron ‘microscope’ is the major breakthrough in materials research and we use it to look at everything. There are things we’ve never seen before,” Zhang said.
The research, “Dynamic Odd-Even Effect in Liquid n-Alkanes near Their Melting Points,” has been published in Angewandte Chemie International Edition. The German publication is one of the top chemistry journals in the world. The reported research discovery is fundamental to understand and improve a wide spectrum of chemical processes, such as lubrication, diffusion through porous media, and heat transfer.
Zhang conducted the research after being selected in fall 2015 for an American Chemical Society Petroleum Research Fund Doctoral New Investigator Award. The first author of the paper, Ke Yang, graduated in summer 2016 and now works at the Dow Chemical Company.
Plant biologists have bumped up crop productivity by increasing the expression of genes that result in more efficient use of light in photosynthesis, a finding that could be used to help address the world’s future food needs.
Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California, Berkeley (UC Berkeley), and the University of Illinois targeted three genes involved in a process plants use to protect themselves from damage when they get more light than they can safely use. By increasing the expression of those genes, the scientists saw increases of 14-20 percent in the productivity of modified tobacco plants in field experiments.
The researchers described their findings in a paper published today in the journal Science.
“Tobacco was used as the model crop plant in this study because it is easy to work with, but we’re working to make the same modifications in rice and other food crops,” said co-senior author Krishna Niyogi, a faculty scientist in Berkeley Lab’s Division of Molecular Biophysics and Integrative Bioimaging. “The molecular processes we’re modifying are fundamental to plants that carry out photosynthesis, so we hope to see a similar increase in yield in other crops.”
Niyogi, who is a Howard Hughes Medical Institute investigator and a UC Berkeley professor of plant and microbial biology, teamed up with Stephen Long, a plant biology and crop sciences professor at the University of Illinois, for the study.
In photosynthesis, plants use the energy in sunlight to take up carbon dioxide from the atmosphere and convert it into biomass, which we use for food, fuel, and fiber. When there is too much sunlight, the photosynthetic machinery in chloroplasts can be damaged, so plants need photoprotection. Inside chloroplasts, plants have a system called NPQ, or nonphotochemical quenching, for this purpose.
Niyogi compared NPQ to a pressure relief valve in a steam engine.
“When there is too much sunlight, it’s like pressure building up,” said Niyogi. “NPQ turns on and gets rid of the excess energy safely. In the shade, the pressure in the engine decreases. NPQ turns off, but not quickly enough. It’s like having a leak in the system with the valve left open. The photosynthetic engine can’t work as efficiently.”
The highly variable levels of light plants receive, particularly in densely planted crop fields, presents a challenge to the efficient use of solar energy. Plants must adapt to intermittent shading from leaves that are higher in the canopy, or from passing clouds.
Niyogi and his postdoctoral research associates Lauriebeth Leonelli, Stéphane Gabilly, and Masakazu Iwai figured out a way to speed up recovery from photoprotection and demonstrated a proof of this concept in the laboratory. They used a new method to rapidly test gene expression in tobacco leaves. By boosting the expression of three genes involved in NPQ, they showed that NPQ turned off more quickly, and the efficiency of photosynthesis in the shade was higher.
Half of crop photosynthesis occurs in the shade, so any improvement in speeding up recovery from photoprotection could have a big benefit, the researchers said.
Illinois postdoctoral researchers Johannes Kromdijk and Katarzyna Glowacka took the trio of genes studied at Berkeley and put them into tobacco plants for further testing in greenhouse and field experiments.
The work to boost crop productivity comes as concerns about food shortages rise with the world’s population. The Food and Agriculture Organization of the United Nations estimates that food production will need to nearly double by 2050 to meet increasing demand. Yields of the world’s major staple crops have not been increasing fast enough to meet this projected need.
“My attitude is that it is very important to have these new technologies on the shelf now because it can take 20 years before such inventions can reach farmer’s fields,” said Long. “If we don’t do it now, we won’t have this solution when we need it.”
Researchers from the University of Illinois at Urbana-Champaign have demonstrated doping-induced tunable wetting and adhesion of graphene, revealing new and unique opportunities for advanced coating materials and transducers.
“Our study suggests for the first time that the doping-induced modulation of the charge carrier density in graphene influences its wettability and adhesion,” explained SungWoo Nam, an assistant professor in the Department of Mechanical Science and Engineering at Illinois. “This work investigates this new doping-induced tunable wetting phenomena which is unique to graphene and potentially other 2D materials in complementary theoretical and experimental investigations.”
Graphene, being optically transparent and possessing superior electrical and mechanical properties, can revolutionize the fields of surface coatings and electrowetting displays, according to the researchers. A material’s wettability (i.e. interaction with water) is typically constant in the absence of external influence and are classified as either water-loving (hydrophilic) or water-repelling (hydrophobic; water beads up on the surface). Depending on the specific application, a choice between either hydrophobic or hydrophilic material is required. For electrowetting displays, for example, the hydrophilic characteristics of display material is enhanced with the help of a constant externally impressed electric current.
“What makes graphene special is that, unlike conventional bulk materials, it displays tunable surface wetting characteristics due to a change in its electron density, or by doping,” said Ali Ashraf, a graduate student researcher and first author of the paper, “Doping-Induced Tunable Wettability and Adhesion of Graphene,” appearing in Nano Letters. “Our collaborative research teams have discovered that while graphene behaves typically as a hydrophobic material (due to presence of strongly held air-borne contamination on its surface), its hydrophobicity can be readily changed by changing electron density.
Researchers have created a robotic mimic of a stingray that’s powered and guided by light-sensitive rat heart cells.
The work exhibits a new method for building bio-inspired robots by means of tissue engineering. Batoid fish, which include stingrays, are distinguished by their flat bodies and long, wing-like fins that extend from their heads. These fins move in energy-efficient waves that emulate from the front of the fin to the back, allowing batoids to glide gracefully through water. Inspired by this design, Sung-Jin Park et al. endeavored to build a miniature, soft tissue robot with similar qualities and efficiency. They created neutrally charged gold skeletons that mimic the stingray’s shape, which were overlaid with a thin layer of stretchy polymer.
- Today most U.S. biodiesel is produced from soybean. But despite its value as a protein source, soybean only provides the equivalent of about one barrel of oil per acre.
- A team led by the University of Illinois has engineered sugarcane plants to produce 12 percent oil by weight, and expect to reach 20 percent in the future. This could provide 17 barrels of oil per acre.
- Biodiesel from “oil cane” could reduce the cost of biodiesel production from $4.10 to $2.20 per gallon and provide additional environmental and economic benefits.
America’s oil consumption far exceeds that of every other country in the world. What’s more, it’s unsustainable.
Therefore, in 2007, Congress mandated a move away from petroleum-based oils toward more renewable sources. Soybeans, an important dietary protein and the current primary source of plant-based oils used for biodiesel production, only yield about one barrel per acre. At this rate, the soybean crop could never quench the nation’s thirst for oil.
To address this issue, the Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-E) program called for high-risk, high-reward projects that could develop new drop-in fuels in its PETRO program. A team led by University of Illinois researchers answered the call by imagining and successfully achieving a way to produce large quantities of oil from sugarcane. Their most recent study demonstrates the economic benefits of this technology relative to soybean oil.
“We thought that if we could go back to the drawing board, we’d need a very productive crop. And we would also need something that could grow on land that isn’t being used intensively for food. We came up with sugarcane and sweet sorghum,” recalls Stephen P. Long, U of I crop scientist and lead investigator on the project.
The team altered sugarcane metabolism to convert sugars into lipids, or oils, which could be used to produce biodiesel. The natural makeup of sugarcane is typically only about 0.05 percent oil. Within a year of starting the project, the team was able to boost oil production 20 times, to approximately 1 percent. At the time of this writing, the so-called “oil-cane” plants are producing 12 percent oil. The ultimate goal is to achieve 20 percent. Oil cane has additional advantages that have been engineered by the team. These include increased cold tolerance and more efficient photosynthesis, which leads to greater biomass production and even more oil.
“If all of the energy that goes into producing sugar instead goes into oil, then you could get 17 to 20 barrels of oil per acre,” Long explains. “A crop like this could be producing biodiesel at a very competitive price, and could represent a perpetual source of oil and a very significant offset to greenhouse gas emissions, as well.”
In their analysis, the team looked at the land area, technology, and costs required for processing oil-cane biomass into biodiesel under a variety of oil production scenarios, from 2 percent oil in the plant to 20 percent. These numbers were compared with normal sugarcane, which can be used to produce ethanol, and soybean.
An advantage of oil cane is that leftover sugars in the plant can be converted to ethanol, providing two fuel sources in one.
“Modern sugarcane mills in Brazil shared with us all of their information on energy inputs, costs, and machinery. Then we looked at the U.S. corn ethanol industry, and how they separated the corn oil. Everything we used is existing technology, so that gave us a lot of security on our estimates,” Long says.
The analysis showed that oil cane with 20 percent oil in the stem, grown on under-utilized acres in the southeastern United States, could replace more than two-thirds of the country’s use of diesel and jet fuel. This represents a much greater proportion than could be supplied by soybean, even if the entire crop went to biodiesel production. Furthermore, oil cane could achieve this level of productivity on a fraction of the land area that would be needed for crops like soybean and canola, and it could do so on land considered unusable for food crop production.
The current full production cost of biodiesel from soybean is $4.10 per gallon ($1.08 per liter). Using oil cane instead, that cost decreases to $3.30 per gallon for 2 percent oil cane and to $2.20 per gallon for 20 percent oil cane. The ethanol produced from 1-, 5- and 10 percent oil cane would add to the cost benefit.
Although $2.20 per gallon does not represent a large savings over the current price of gasoline in the United States, Long cautions consumers and politicians to look at the bigger picture.
“We know from our past experience that it’s not going to last,” he says. “We need to start building for a future when gas is no longer as low as $1.50 per gallon, and we need to avoid any future dependency on other countries for our oil. We are lucky to have the land resources to do this and, in doing so, to ensure that future generations have a supply of oil that is domestic and renewable.”
Solar Cell from Berkeley Lab/University of Illinois Absorbs High-Energy Light at 30-fold Higher Concentration than Conventional Cells
By combining designer quantum dot light-emitters with spectrally matched photonic mirrors, a team of scientists with Berkeley Lab and the University of Illinois created solar cells that collect blue photons at 30 times the concentration of conventional solar cells, the highest luminescent concentration factor ever recorded. This breakthrough paves the way for the future development of low-cost solar cells that efficiently utilize the high-energy part of the solar spectrum.
“We’ve achieved a luminescent concentration ratio greater than 30 with an optical efficiency of 82-percent for blue photons,” says Berkeley Lab director Paul Alivisatos, who is also the Samsung Distinguished Professor of Nanoscience and Nanotechnology at the University of California Berkeley, and director of the Kavli Energy Nanoscience Institute (ENSI), was the co-leader of this research. “To the best of our knowledge, this is the highest luminescent concentration factor in literature to date.”
Read more: Made from Solar Concentrate