Catalyst of discovery

Energy research breakthroughs powered by UW-Madison

February 29, 2016

 

Scalable solutions to meet increasing global demand, innovative ideas for power storage, grand changes to the grid, or small tweaks to boost efficiency.

Pick an energy challenge facing our world and there’s likely a lab ticking away at solutions on the UW-Madison campus, whether from the perspective of technology, policy, economics or social impact.

The result: cross-cutting, high-impact efforts such as these, from all corners of campus, that advance clean, efficient and cost-effective energy solutions.

WEAVING CHEMISTRY INTO DESIGN

Merging science and art, Trisha Andrew, an assistant professor of chemistry, and Marianne Fairbanks, an assistant professor of design studies, are working together toward a potentially transformative idea: building solar cells on fabric to create usable, even wearable, technologies.

“If we take this technology to grow devices on material, then we could talk wearable technology, as well as solar curtains, solar umbrellas, solar tents, or applications for the military,” Andrew says.

Though Fairbanks and Andrew are not the first to conceive of solar textiles, their collaboration overcomes a manufacturing challenge that Andrew says is slowing the rollout of cheap, consumer-friendly solar cells – namely, the early integration of technologies emerging from the lab with actual manufacturing processes.

The pair is experimenting with several methods, including coating different fabric weave types and structures with a polymer that increases conductivity tenfold, and they hope to soon develop prototypes and proofs of concept.

BIOMASS-TO-TRANSPORTATION PARTNERSHIPS

A new two-year agreement between UW-Madison and ExxonMobil will power research into the chemistry of converting biomass into transportation fuels, pairing the university’s expertise with the company’s resources and technology development.

“The science of biomass conversion is very complicated,” says George Huber, the Harvey D. Spangler professor of chemical and biological engineering. “We are doing the long-term fundamental research to understand the chemistry involved.”

Huber’s group has been working with ExxonMobil to develop new catalytic materials for biomass conversion that are orders of magnitude cheaper than precious-metal catalysts. That could help make biomass fuels cost-competitive with petroleum.

Huber is also part of a UW-Madison team supported by a $3.3 million U.S. Department of Energy grant to analyze the biomass production process. He and other campus researchers are creating biofuel products worth more than $5,000 per ton, compared to $600 to $700 per ton for other biofuels – a step toward using biomass resources more efficiently, he says.

A NEW LOOK AT AN OLD ENGINE

While many UW-Madison researchers have their eyes set on the future of energy, Rolf Reitz and Sage Kokjohn, professors of mechanical engineering, are working to bring the century-old technology of the internal-combustion engine up to pace with the 21st century.

The internal-combustion engine is a valued method for converting energy into mechanical work. But to make improvements for efficiency and flexibility, the researchers believe a new set of principles is needed.

Reitz, Kokjohn and campus colleagues in the Engine Research Center revamped the engine technology to deliver a constantly adjusted mixture of diesel and gasoline for maximum efficiency. They call this advancement reactivity controlled compression injection, or RCCI.

RCCI can also be applied to engines that use biofuel, a discovery that could especially help developing nations steer away from fossil fuels that contribute to global warming, yet still take advantage of the accessibility of internal-combustion engines.

SMALL CHANGES, BIG BENEFITS

Two-thirds of the electricity used on Earth goes to powering a motor of some kind. Dan Ludois, assistant professor of electrical and computer engineering, spends a majority of his research questioning the ubiquitous nature of that technology.

Ludois knows motor technology isn’t likely to get phased out, so his approach is to make behind-the-scenes improvements that reduce the energy footprint of motors. How? Transform and replace existing technologies with more efficient physical principles, materials and manufacturing techniques, which he believes are relatively easy to implement in a range of industrial situations.

“If you can make small changes, you can have extreme benefits,” he says.

For example, his spinoff company C-Motive recently created a motor that uses electrostatic force rather than magnetic fields, which eliminates the need for magnets and reduces the use of rare-earth metals.

COAXING SUNLIGHT INTO GREATER ENERGY YIELDS

Can solar energy help meet global energy demand? For Zongfu Yu, an assistant professor of electrical and computer engineering, that reality starts with improving the technology’s efficiency on a small scale.

So small, in fact, that he and his collaborators are working to understand and control the behavior of light itself. At the intersection of optics and materials science, Yu is working to improve photovoltaics (PVs).

Thanks to advances in nanotechnology, it’s now possible to create solar cells that wring more energy from the photons in sunlight. Yu’s aim is to manipulate light into staying longer on the surface of PV cells, which in turn could produce a 5- to 10-percent increase in energy conversion efficiency.

“I’m very, very positive on solar energy, because if you look at how the efficiency is gradually improving — even though this or that company may or may not be doing well — the technology has never stopped evolving,” he says.

SEEKING MORE SUSTAINABLE BIOFUELS

In an attempt to fill gas tanks with more environmentally sustainable biofuels, Great Lakes Bioenergy Research Center scientists are moving beyond corn and other first-generation biofuel feedstocks to mixed varieties of perennial grasses such as switchgrass.

Perennial grasses carry an array of ecological benefits, from reducing soil erosion to suppressing the invasion of agricultural pests. But adding perennial cropping systems is a major transition for farmers accustomed to tending monoculture crops like corn.

Moving biofuel cropping toward long-term sustainability and profitability will require a better understanding of how perennial grasses develop under differing conditions. Doctoral researcher Laura Smith, for example, is studying the relationship between biomass productivity and nitrogen uptake in switchgrass fields. The goal: reduce the use of nitrogen fertilizer, while still achieving highly productive harvests – good for the farmer and for the environment.

“It’s about how we can grow what we need and nurture the land at the same time,” says agronomy professor and Nelson Institute affiliate Randy Jackson.

X-RAY BATTERY VISION

In a move that could improve the energy storage of everything from portable electronics to electric microgrids, UW-Madison and Brookhaven National Laboratory researchers have developed a novel X-ray imaging technique to visualize the electrochemical reactions in rechargeable lithium ion batteries containing a new type of material, iron fluoride.

“Iron fluoride has the potential to triple the amount of energy a conventional lithium-ion battery can store,” says Song Jin, a professor of chemistry and Wisconsin Energy Institute affiliate. “However, we have yet to tap its true potential.”

The collaborators used a state-of-the-art transmission X-ray microscope at Brookhaven to collect chemical maps from actual coin cell batteries filled with iron fluoride during battery cycling, to determine how well they perform. The resulting nanoscale visualizations and measurements now offer new insights to help tackle challenges facing the material’s use in batteries, and to imagine a broader range of applications.

WINDOW CLOSING FOR BIOFUEL CROPS?

If Wisconsin wants to be a leader in biomass production for biofuels, things need to change, and soon, concludes recent research from David Mladenoff, a professor of forest and wildlife ecology and faculty affiliate of the Nelson Institute.

Mladenoff found that the state’s window of opportunity for biomass production is closing due to recent land cover changes. The “open lands” originally envisioned for growing biofuel crops in Wisconsin and other Great Lake states are being converted to other uses; between 2008-13, these states saw a 37 percent reduction of non-agricultural open lands, with most of that land transitioning to row-crop agriculture.

The research also found that many of the landscapes considered “open lands” provide a variety of valuable ecosystem services, which are being lost as the lands are converted.

Mladenoff says it will be hard to alter this trend, largely driven by current policies and incentives for corn ethanol.

POWERING MILWAUKEE MANUFACTURING

On the same site in Milwaukee where the A. O. Smith Corporation once built airplane and auto parts for the military during both world wars, UW-Madison energy researchers are using state-of-the-art microgrid technology – small, self-contained electric power systems that can seamlessly connect and disconnect from the traditional power grid – to help revitalize Milwaukee’s industry.

UW engineers have teamed up with the Mid-West Energy Research Consortium to design a microgrid-based electric power and distribution system that supports Milwaukee’s Century City Business Park. City developers are hopeful that the advanced manufacturing and research hub will bring increased economic stability to Milwaukee, where the poverty rate currently approaches 30 percent.

The microgrid’s ability to function independently and cooperatively with the power grid benefits system stability and reliability, and allows customers and utilities to save energy by using waste heat and generating electricity locally when needed – technologies and features that UW-Madison is an international leader in developing.

MOLECULAR CATALYSTS HOLD PROMISE

In the quest for better, less expensive ways to store and use energy, platinum and other precious metals play an important role. They serve as catalysts to propel the most efficient fuel cells, but they are costly and rare.

Now, a metal-free alternative catalyst for fuel cells may be at hand. UW-Madison chemistry Professor Shannon Stahl and lab scientist James Gerken have introduced a new approach that uses a molecular catalyst system instead of solid catalysts. Although molecular catalysts have been explored before, earlier examples were much less efficient than traditional platinum.

The new creation – “the most effective molecular catalyst system ever reported,” Stahl says – is composed of a mixture of nitroxyls and nitrogen oxides, molecular partners that play well together; one reacts well with the electrode, while the other reacts efficiently with the oxygen.

EXPANDING GEOTHERMAL ENERGY

Could geothermal energy soon heat and cool more homes? Eleanor Bloom, a graduate student in geological engineering, hopes so.

Small-scale geothermal systems can be installed almost anywhere, Bloom says. Water runs through pipes from a ground-source heat pump in a home’s basement, then either sheds thermal energy back into the ground to cool the house, or delivers it to the home for heating.

Bloom is a member of engineering Professor James Tinjum’s research team, which is evaluating a geothermal system at a rural Wisconsin home, and helping to reduce obstacles to its more widespread use.

UW-Madison geoscientists and engineers are also working with industry and the U.S. Department of Energy on a monitoring system for geothermal wells, converging on Brady Hot Springs in Nevada to turn a small geothermal field into a proving ground for a system that could be scaled for wider and deeper fields.

ENGINEERING BETTER BACTERIA

By better understanding metabolism in biofuel-producing bacteria, Daniel Amador-Noguez, an assistant professor of bacteriology, is engineering microbes that can more efficiently convert plant biomass to energy.

One recent project sought to understand how a toxin produced from lignin (the woody backbone of plants) during the breakdown of plant biomass inhibits the conversion of plant sugars into biofuels. Research revealed that, in general, these “lignotoxins” are powerful inhibitors of the enzymes the cell needs to synthesize nucleotides, which are essential to the cell’s DNA. Scientists can now search for ways to direct the affected enzymes to be more resistant to lignotoxins, or to break the connections that allow these inhibitors to work.

Jennifer Reed, an associate professor of chemical and biological engineering, is also exploring ways to improve these processes.

For example, microbes do not readily convert xylose, a sugar found in biofuels feedstocks like corn stover and switchgrass, into biofuels. So studying how to get microorganisms to metabolize xylose is a step toward generating as much product as possible while taking advantage of all materials available – research that earned Reed a Presidential Early Career Award for Scientists and Engineers.

AMPED UP LAB SPACE

Step into the Johnson Controls Advanced Systems Test Lab at the Wisconsin Energy Institute and you can see an electric pickup truck outfitted with sensors that measure almost every aspect of the vehicle’s function. Nearby, a researcher might be testing how a car battery reacts to drawing constantly changing currents in a simulated driving experiment.

These projects and others, using state-of-the-art equipment donated by Johnson Controls, are helping to evaluate and optimize how battery systems perform and interact with a vehicle’s powertrain and electrical architecture.

UW-Madison’s partnership with the Milwaukee-based company began in 2014 to study energy storage technology and build systems that utilize battery power more efficiently. By examining how batteries behave while drawing or charging energy, WEI researchers can test cutting-edge concepts and amass a treasure trove of data and insights into how to manage, track and enhance energy storage components.

Research excerpts based on stories by Libby Dowdall, Krista Eastman, Scott Gordon, Mark Griffin, Nicole Miller, Silke Schmidt and Leslie Shown. To learn more about energy research, education and outreach at UW-Madison, visit energy.wisc.edu.