Clean Energy Systems: Transitioning to a sustainable future

Newswise — Since the 1800s, energy demand and consumption has continually increased and roughly 80% of the world’s energy today comes from the use of fossil fuels—coal, oil and natural gas. Burning of fossil fuels has led to widespread negative impacts: production of CO₂ that has led to warming of Earth’s atmosphere, contribution to local air pollution and innumerable environmental hazards caused by fossil fuel extraction processes. To mitigate these effects of climate change and to develop a sustainable energy landscape, the world is transitioning to using renewable and clean energy sources. However, this transition is faced with many obstacles including lack of infrastructure, initial costs of development and installation, public opinion, suitable energy storage, etc. 

Despite the challenges presented by the changing climate, it also allows for innovation and research, whether that is new energy systems or reimagining existing systems. To hit carbon-neutral goals set forth by the United States and the world, paradigm shifts must be made. Today’s climate crisis won’t be solved by one person alone but rather by researchers in all fields working towards a common goal. Grainger engineers are leaders in the efforts to develop the energy systems needed to achieve a cleaner, carbon-free world. 

Batteries

As the world transitions from using fossil fuels, batteries play a critical role in enabling the use of renewable energy sources. To use those new energy sources at high levels on the grid, the ability to store electricity and use it at a later time is essential. Although renewable energy sources are inherently intermittent, batteries can help seamlessly integrate more clean energy into the grid and decrease reliance on fossil fuels.  

“There’s been a lot of growth in the energy storage space,” says Paul Braun, a professor of materials science & engineering and director of the Materials Research Laboratory. “There’s a wide range of end-use cases and there’s not one battery that fits all cases. One of the challenges is coming up with battery designs for end-use case that are cost-effective at scale. Providing the required performance at an acceptable cost at-scale is key.” 

There are different categories of end-use cases for batteries: stationary (electric grid storage), small personal mobility (electric scooters and bikes), personal vehicles (regular cars and trucks), and heavy trucks (UPS trucks, school buses, semi-trucks, etc.). The batteries for each of these categories have different performance characteristics such as energy density, power density, operating conditions, and expected lifetime.  

Braun and his group are working on developing materials that would enable batteries to operate at higher temperatures. Currently, batteries for electric vehicles (EVs) have an ideal operating range of about 70°F (room temperature) to about 120°F. To keep batteries in that range, the battery must be actively heated and cooled. “To simplify the cooling system design,” Braun says. “We would like to design batteries to operate up to 170°F or perhaps even 200°F. Our goal is to have batteries with similar performance characteristics as what you would get in today’s designs but use materials which are compatible with higher temperature operation.” 

As electrification continues to increase, a major concern is the recycling of spent batteries. Braun’s group also looks at how used batteries can be very effectively converted into new batteries. He says, “Today’s recycling methodologies are pretty inefficient and very energy intensive. We’re working on ideas to grow new batteries from old batteries. The premise is to take the old battery, dissolve the active part off one electrode, put in a new electrode current collector and deposit new material on that current collector. You’d be able to form new batteries almost directly from old batteries.”  

Batteries today can be recycled, but recycling needs to be made more cost-effective. Braun explains, “If the nickel and cobalt and lithium required to make a new battery can be extracted from a used battery in an environmentally friendly way, for half the cost of getting it out of the ground, everyone will recycle batteries, if only to save money. Once this is the case, there is a direct financial benefit to the consumer to recycle used batteries.”

Hydrogen

“We are at a unique point in history,” says Petros Sofronis, a professor of mechanical science & engineering and principal investigator at the International Institute for Carbon-Neutral Energy Research at Kyushu University in Japan, co-hosted by the Grainger College of engineering. “There is massive investment in the hydrogen space by the Biden-Harris administration, as well as in Europe and Japan, that has never happened before. We are at a crossroads, and here in the Midwest and in the state of Illinois we are moving rapidly ahead.”  

On the national level, the U.S. Department of Energy’s Energy Earthshots Initiative aims to accelerate breakthroughs of more abundant, affordable and reliable clean energy solutions to tackle the toughest remaining barriers to addressing the climate crisis and achieving net-zero carbon emissions by 2050. Specifically, the Hydrogen Energy Shot seeks to reduce the cost of clean hydrogen by 80% in one decade.  

Regionally, the Midwest Alliance for Clean Energy (MachH2), of which Grainger Engineering is a member, will enable decarbonization by strategic hydrogen uses in various sectors. More locally, the Illinois Hydrogen Economy Task Force aims to identify opportunities, assess roadblocks, and recommend government policies to catalyze the deployment of hydrogen into the state’s economy.  

“The idea is to develop the technology that will transform the economy—a hydrogen-fueled Midwestern economy,” says Sofronis, who is also a member of this Task Force. Reducing the price and advancing hydrogen technology will accelerate its use in many application spaces including steel manufacturing, clean ammonia, heavy-duty transportation, sustainable aviation and synthetic fuels, and energy storage for the electric grid and power generation.  

Hydrogen can be produced through several processes, one of which is relatively clean—electrolysis—which separates water molecules into hydrogen and oxygen by using renewable or nuclear energy sources. However, one of the main challenges in the wide adoption of hydrogen is embrittlement, a process by which interaction with hydrogen reduces the resistance of materials again fracture. “From room temperature to very high temperatures, hydrogen interacts with materials, and unfortunately, its impact is negative. It makes the materials fragile,” Sofronis says.  

Sofronis is working with a team of colleagues in Grainger on a specific class of low-cost steels that show promise of being resistant to the effects of hydrogen embrittlement. However, this class of steel is very expensive. “We are trying to reduce the cost of these materials by investigating how the elemental composition of these steels interacts with potential deformation mechanisms that are known to impact their resistance to failure,” Sofronis explains.  

He is also looking at a problem called high temperature hydrogen attack. At high temperatures, commonly prevalent in equipment in refineries and petrochemical facilities, internal methane bubbles are generated in the material which can cause it to blow apart. “We want to develop a model that captures the underlying chemomechanical phenomena and microstructural conditions upon failure and propose a new reliable tool to ascertain fitness-for-service of components in service,” Sofronis says. 

Nuclear

“Nuclear energy plays an essential role in the quest for clean, reliable energy,” says Caleb Brooks, a professor of nuclear, plasma & radiological engineering and director of the Illinois Microreactor Research, Development & Demonstration Center. 

“Microreactors are a new class of fission technology that we believe to be well-positioned to change the paradigm around nuclear energy,” Brooks explains. “It’s really critical that we have nuclear technology for our climate goals and overall reliability and resiliency of the electric grid. If we’re serious about decarbonization, we need fission technology that can decarbonize some of the larger industrial sectors that are challenging to electrify.” 

A microreactor is a small nuclear reactor that can generate 1 to 20 megawatts (MW) of energy which can be used to generate electricity for the grid and provide heat for those larger industrial sectors. Such a small physical footprint provides a lot of flexibility in its siting and allows the reactor to be transported by truck to even remote destinations. Brooks says that with the smaller size comes a very strong safety case on already very safe technology. 

Traditional nuclear plants have upfront capital costs of several billion dollars with a construction timeline that spans several years, even without delays. Microreactors, on the other hand, are only a fraction of the cost with the components of the reactor fully assembled in a factory and then shipped out to its permanent location. The portability of the microreactor makes it ideally suited for use in emergency response scenarios where it can be quickly deployed to regions hit by natural disasters.  

Illinois, through the department of nuclear, plasma & radiological engineering, is currently in the process of applying for a license to construct and operate a new research microreactor on campus. Historically, nuclear research reactors have been operated safely and efficiently on university campuses across the nation. The Illinois Microreactor RD&D Center aims to bring the next generation of nuclear research reactors to our campus and advance the commercial readiness of advanced reactor technology via education, research and at-scale demonstrations. 

“Our project is about the need to demonstrate the new type of technology, microreactors, in all phases: the way we build, license, construct and operate them. All of these things can now change because of the way that the technology is being developed. But we need to demonstrate that change,” Brooks says.  

Once approved and operational, the campus microreactor would be able to generate 10 MW that can power continuously for 20 years without the need to refuel. Through multiple refuelings, the reactor will be able to provide clean power for decades to come. Beyond the energy generation of the reactor itself and the related research, output from this project will include education. Traditional nuclear has typically been inaccessible to the public and as many university research reactors have been shut down, there is now a gap in students with hands-on experience. Deployment of a reactor at Illinois will help develop the workforce and engage the public to create confidence and trust in nuclear power.  

Wind

“Floating offshore wind is a very interesting and rich design problem,” says James Allison, a professor of industrial & enterprise systems engineering. “My group uses advanced engineering design methods to achieve the goals of accelerating new energy technologies and reducing the cost of energy.” 

Another DOE Energy Earthshot initiative is the Floating Offshore Wind Shot, which aims to transition densely populated coastal regions to clean energy and reduce the cost of floating offshore wind energy by more than 70%. Approximately two-thirds of offshore wind energy potential in the U.S. exists over waters that are too deep to anchor a traditional wind turbine.  

Despite the potential for significant energy production, wind turbines present a unique design challenge where systems are typically designed sequentially. First starting with the aerodynamic design, such as the design of the blades. Then moving to the structural design, such as ensuring that the blades and the tower are strong enough. And then finally, the control design, which determines things like what the blade pitch should be at different operating conditions.  

“But with this sequential approach to design, we miss out on opportunities for synergy between these different areas,” Allison says. “Control co-design refers to the holistic design or integrated design of actively controlled engineering systems, where we simultaneously look at how we should design the physical and control aspects of the system.” 

Floating offshore turbines create an even more interesting design problem. Allison explains, “If we have a wind turbine on a floating platform, we have additional degrees of freedom, and it’s going to be more dynamic. The platform will move around from waves, ocean currents, wind and weather, and if we use a control system intended for land-based turbines, the floating platform will be an unstable system. We need totally different control systems for this because it’s a much more complicated thing.” While these marine environments are very extreme, there are also a lot more energy resources offshore, making it a worthwhile prospect.   

Recent DOE-supported research at Illinois has used control co-design to discover new lightweight, low-cost floating wind energy systems robust enough to operate reliably at sea, providing an economically viable path to harness the vast energy resource of deepwater wind.  

Advanced engineering design methods such as control co-design can be used for more than just floating offshore wind. Allison also researches hydrokinetic turbines, which are smaller-scale underwater turbines that can be placed in rivers or ocean currents. Such turbines can be installed in remote locations, such as a small village in Alaska, where energy from the grid isn’t an option and residents are competing with the cost of electricity produced by a diesel generator, which is more expensive and less clean.  

“I spend a lot of my time looking for opportunities for synergy, looking at the interface between aspects of a system,” Allison says. “The interface could be the physical interface between things or the interface between different technical disciplines. If we are working with a more siloed approach, then we often miss out on opportunities to improve the overall system.” 

Grainger Engineering is also leading efforts in the broader area of electrification, with several centers focused on advancing both the underlying technologies and workforce needed to facilitate an electrified world.

POETS

The Center for Power Optimization of Electro-Thermal Systems, aims to improve the power density of next generation electro-thermal systems by integrating research efforts in mechanical, electrical and materials engineering domains. As electrification efforts have increased, it is vital to also increase the power-to-weight (or power-to-volume) ratio for electrified components, such as motors, electronics and batteries. POETS enables the increase in power density through both its advanced technology and workforce development, from beginning design concept and optimization through actual deployment in field testbeds.

CEME

The Center for Electrical Machinery and Electromechanics, is dedicated to enhance education, technology, understanding and research activities on the fundamental topic of electric machinery—the “muscle” of modern civilization. Advances in engineering materials, electronic devices, semiconductor processes, computer simulation and many other areas can improve the design and operation of the billions of motors in use across the world. CEME is nurturing a new generation of engineers for contributions to rotating electric machines and electromechanics through specialized training and experiences at all levels of higher education.

CHEETA

The Center for High-Efficiency Electrical Technologies for Aircraft, is a multi-disciplinary consortium of researchers, scientists and engineers from various universities, laboratories and industry groups. Electric propulsion offers a new paradigm for the design of modern aircraft systems and CHEETA aims to develop, mature and design disruptive technologies for these systems. Research is focused on distributed electric propulsion, electrical components, energy storage and systems integration.