Developing and testing hydrogen production, use, and storage
Generating electricity from sources that do not emit greenhouse gases, or that emit low levels of them, is key to the overall mix of solutions for climate change. These sources include wind and solar. Nuclear also has a role to play in a decarbonizing world.
And while there are many ways to deploy green electricity, several Northwestern researchers see hydrogen production as an important avenue. Hydrogen is a clean fuel source and a carrier that can be used to store and deliver energy from other sources.
Hydrogen, when produced from renewable or nuclear electricity, can ultimately help decarbonize high-polluting industries, mitigate climate change, and reduce emissions while creating more jobs — a vision called the “hydrogen economy.”
The results could both reduce greenhouse gasses and mitigate local pollutants. What if electric vehicles ran on hydrogen-powered fuel cells, for example.
“Imagine all the truck traffic on I-90,” said Jennifer Dunn, professor of chemical and biological engineering. “It generates particulate matter emissions that affects the health of nearby communities. If you use hydrogen to power those trucks, those communities would have cleaner air.”
But barriers to widespread hydrogen use remain. Producing hydrogen using electricity is not competitive with producing it with today’s technology, which uses steam reforming of natural gas. Hydrogen needs much more storage space and infrastructure for shipping and delivery than other energy carriers. Safety concerns also must be addressed as hydrogen infrastructure expands.
As part of the Paula M. Trienens Institute for Sustainability and Energy’s Deploy pillar, Northwestern is leading the development and testing of hydrogen production, use, and storage. The pillar is one of Trienen’s Six Pillars of Decarbonization aimed at leading interdisciplinary research in decarbonization.
“Ultimately, we need green electricity to realize the benefit of sources like hydrogen,” said Dunn, who co-leads the pillar. “But we want to be sure that these hydrogen technologies are ready to use when green electricity is abundant. We want to be part of the national conversation on what it will take to realize the hydrogen economy.”
Today, most hydrogen is developed using fossil fuels — either by steaming natural gas or through electrolysis, a process that splits water into hydrogen and oxygen, which generally uses electricity generated from fossil fuels. Hydrogen made from carbon-free sources (such as solar or wind) is still not cost effective.
The goal is to reduce the cost of clean hydrogen to a dollar per kilogram. Then, the Department of Energy (DOE) anticipates that it could be a game-changer as a fuel source and energy storage medium.
“The goal is to make the cost of hydrogen so low that there is no excuse not to use it, and then we can solve policy issues around it because it is so inexpensive,” said Sossina Haile, Walter P. Murphy Professor of Materials Science and Engineering and co-lead of the Deploy pillar. “It’s an ambitious goal, but it’s possible, and everything we are doing at the Trienens Institute is contributing to that possibility.”
Several initiatives at Northwestern are working toward low-cost, clean hydrogen. Northwestern is a key partner in the Midwest Alliance for Clean Hydrogen (MachH2), one of seven regional clean hydrogen hubs funded by the DOE. MachH2, a public-private entity, is working to promote commercially scalable projects that will stimulate clean hydrogen production and supply hydrogen to end users. The hub plans to produce tens of thousands of metric tons of hydrogen per year.
Dunn serves as the project’s chief decarbonization officer and is focusing on quantifying greenhouse gasses emitted in making and using hydrogen. Hydrogen gas made from natural gas, for example, is cost-effective but emits more greenhouse gasses than other processes. “We have parallel needs: decarbonize the grid and develop technology for using electrochemistry to produce hydrogen,” she said.
Dunn, whose expertise lies in life cycle analysis of emerging technologies, is also working on evaluating tax credit policy for producing hydrogen from green energy sources. “The framing of tax credit eligibility for hydrogen producers in the U.S. is really interesting with stipulations including proving that they used green electricity that is new or otherwise would have gone unused,” she said. Collaborators in that study include Chiara LoPrete of Penn State University.
Northwestern has also received more than $10 million from the DOE to lead an Energy Frontier Research Center (EFRC) focused on developing hydrogen-based energy technologies called the Center for Hydrogen in Energy and Information Sciences (HEISs).
That center is led by Haile, a fuel cell pioneer who has developed record-performance fuel cells in both electrolysis (for hydrogen production) and power generation. Her colleague Scott Barnett, professor of materials science and engineering and a Faculty Affiliate of the Trienens Institute, has also achieved record performance on these cells at higher temperatures, and is studying how to make them last longer.
Northwestern researchers are also working to make better catalysts for hydrogen production and are studying how to best make ammonia, which has been proposed as a way to store and transport hydrogen. “That would be much more environmentally friendly, would be easier to transport, and would be less leaky,” Haile said.
Northwestern’s research is fueled by faculty including Ted Sargent, executive director of the Trienens Institute, and Linsey Seitz, assistant professor of chemical and biological engineering and a Faculty Affiliate of the Trienens Institute. Partnering with Argonne National Laboratory allows researchers access to facilities to help them characterize materials and processes. Argonne is a partner in HEISs and is involved in MachH2 research.
Ultimately, researchers from the Deploy pillar will build on the research of those working across the Six Pillars of Decarbonization to reduce fossil fuels. Together, they hope to facilitate a transition to clean energy. “If they can create green electricity, we can be ready to help store it,” Dunn said.