UNIVERSITY PARK, Pa. — Energy production and use presents a multilayered challenge that includes technical, social and environmental intricacies. With such a complex challenge at hand, Penn State’s Institutes of Energy and the Environment (IEE) has launched a focused effort called the Consortium for Integrated Energy Systems (CIES). The consortium works to examine the transformation of energy systems more holistically, through unified processes that consider the whole energy portfolio versus addressing individual problems.

CIES is a collection of Penn State researchers working toward an energy future that is sustainable, equitable, and able to keep up with the ever-changing energy infrastructure. The goals of CIES are to facilitate interdisciplinary, solutions-focused research and to develop programs that will train energy’s future workforce.

Eight faculty members have joined CIES, many of whom are new to Penn State. In the College of Engineering:

• Christopher Arges
• Satadru Dey
• Lauren Greenlee
• Mark Miller
• Linxiao Zhu

In the College of Earth and Mineral Sciences:

• Yashar Mehmani
• Nelson Yaw Dzade
• Anne Menefee

Bruce Logan, interim director of CIES and associate director of IEE, said both of the consortium's goals are greatly needed because the energy sector needs to change quickly.

“Our future leaders are going to have to be thinking about numerous facets when it comes to energy,” said Logan, Evan Pugh University Professor and Kappe Professor of Environmental Engineering. “This includes considering how renewable energy sources can be integrated with existing nonrenewables, looking at how to facilitate that transformation, thinking about smart energy systems, energy efficiency, and also how to integrate nonenergy themes that impact climate change.”

Lauren Greenlee, an associate professor in the Department of Chemical Engineering, said a consortium like CIES is crucial to how the energy sector is transforming because it brings people together.

“It really opens up pathways to conversation, ideas and opportunities across the campus, and will accelerate Penn State’s ability to play an important role in different aspects of the energy sector’s transformation,” she said. “Many of the energy challenges today require multiple disciplines and expertise, and for a large institution like Penn State, sometimes it is difficult to find individuals in our community who could work with us to tackle these challenges.”

Anne Menefee, an assistant professor in the John and Willie Leone Family Department of Energy and Mineral Engineering, said global climate and energy challenges are wicked problems that are extremely complex and multidimensional.

“'Sustainable energy' is de facto an interdisciplinary endeavor,” she said. “Developing the technologies draws from a range of engineering disciplines, and economics are often a rate-limiting barrier. If technologies aren't designed within the context of social constructs, they'll be dead-on-arrival.”  

Menefee added that focus areas like CIES are critical to bridging active researchers across emerging energy challenges, as this is an iterative process.

“The sum of these diverse contributions will be much more effective than operating as independent parts,” she said. “Strategically coordinating and building on each other’s efforts will result in more resilient and holistic solutions.”

Emissions

“Merely reducing fossil fuel for our energy infrastructure does not fully solve climate change,” Logan said. “We have to also think about how we solve these other problems while at the same time not adding to fossil fuel emissions by using yet more energy.”

The U.S. energy portfolio is currently changing. Natural gas is now responsible for creating the majority of electricity —approximately 10 exajoules per year. For reference, the U.S. consumes about 14 exajoules of electricity annually. Coal, nuclear and renewables, such as solar or wind energy, each supply approximately half that amount, with coal falling from its lead position in the last decade.

“Natural gas will continue to be a part of the energy future, even as we look to increase renewables,” Logan said. “We should be looking at how we might better use that natural gas to make electricity by using highly efficient gas turbines, which can almost double the amount of efficiency based on heat energy as coal. Additionally, natural gas has about half the carbon emission compared to coal, so switching from coal to natural gas could reduce CO₂ emissions by as much as a factor of four.

“We cannot simply save energy and get to the point where we need to be in terms of reducing CO₂ emissions,” Logan added. “It is also imperative to address both social and technical solutions in the energy future because technology alone will not solve climate change.”

Yashar Mehmani, assistant professor in the Leone Family Department of Energy and Mineral Engineering, said there should be an emphasis on both emission-reduction technologies, like carbon dioxide capture and storage, and zero-emission technologies such as solar, wind, geothermal and hydrogen.

“In terms of education, the public must have a clear understanding of the pending problems facing society, such as climate change and energy transition, including what the penalties for inaction are and what barriers stand in the way,” Mehmani said.

Energy efficiency

According to Linxiao Zhu, assistant professor in the Department of Mechanical Engineering, it is imperative to rethink scenarios with a big energy footprint, such as buildings, heating, cooling, manufacturing and transportation. His research group’s work involves controlling heat and light using novel nanomaterials and structures.

“A big motivation is to harvest clean energy and improve energy efficiency,” Zhu said. “For example, we are currently exploring if sunlight and the cold from outer space can be better used to produce electricity and energy-free cooling. Such clean energy and passive cooling both contribute to reducing emissions. We also created a solid-state device that converts heat to electricity via thermophotovoltaics and a solid-state refrigerator based on light.”

Logan said there are opportunities to make housing more energy-friendly through smart homes, which are a combination of insulation, smart thermometers, high-efficiency heat pumps and solar panels.

Transportation

“We also need to transform our transportation infrastructure by going to electric vehicles charged using renewable energy,” Logan said.

However, Logan recognizes there is a challenge to be overcome when it comes to the weight of batteries and their energy capabilities compared to gasoline. For example, about 2% of a car’s weight is gasoline, but approximately 25% of an electric car’s weight is batteries.

In Christopher Arges’ lab, he and his colleagues are working on high-temperature polymer electrolyte membrane fuel cells for electrifying heavy-duty vehicles, such as long-haul trailer trucks, airline jets and ocean liners.

“Heavy-duty vehicles are difficult to electrify with conventional battery technology as the batteries become too heavy and the charge times are too long for a vehicle meant to be constantly on the road or water, or in the air,” said Arges, associate professor in the Department of Chemical Engineering. “Fuel cells are an electrochemical energy conversion system with no carbon emissions, provided the hydrogen is derived from water electrolysis. Fuel cells can provide continuous power as fuel is available, similar to a gas engine, and do not need to be recharged. They can have higher energy density values than batteries.”

The electrical grid

The power grid was originally designed based on mostly one type of fuel source — fossil fuels — with an endless supply, said Greenlee.

“Now we are looking at a more diverse set of energy sources and some of them are intermittent, such as solar and wind energy,” Greenlee said. “How do we enable the power grid to support variability? At certain times, we have an excess of supply, and at other times, we have power consumption that is more than the instantaneous supply. Storage technologies still lag, and the spikes in variability are difficult for the grid to manage. Also, climate change-induced extremes are getting worse, so the resilience of the power grid is also a challenge.”

People

These are only technical solutions. Logan stresses that people must be considered when developing solutions, and it must be through a global lens.

Mark Miller, an assistant professor in the Department of Aerospace Engineering, said evaluating how people perceive new energy technologies is key to ensuring these solutions remain sustainable and viable long term.

“Often, our desire to have the newest, fastest and most convenient methods of getting from point A to point B conflicts with a choice to be sustainable,” Miller said. “Oftentimes, for new and sustainable options to be fully integrated and accepted, we need to think beyond the technical engineering challenges and into how users interact with or are affected by new technologies."

“People are everything,” added Menefee. “The reality is we've built a society that revolves around energy, and we need to completely revolutionize how energy is sourced and produced to sustain that status quo.”