FuelCellsWorks

One of Professor Eric Wachsman's solid-oxide fuel cells (SOFCs). In the November 18 issue of Science, Wachsman and his colleagues at the University of Maryland Energy Research Center describe how they have been able to create SOFCs with record-setting power density at substantially lower temperatures that can operate on conventional fuels. These lower temperature SOFCs, unlike the more familiar proton exchange membrane (PEM) fuel cells, says Wachsman, will allow industry and the public to reduce their dependence on fossil fuels now without having to wait for a future hydrogen storage and distribution system.

Energy expert advocates investing in “the other fuel cell” to reduce reliance on fossil fuels now, not in decades.

COLLEGE PARK, Md.– When most people hear the words “fuel cell,” they think of eco-friendly, hydrogen-powered cars that emit nothing more than water.

And that, says Professor Eric Wachsman, director of the University of Maryland Energy Research Center (UMERC), is one of the reasons we’re all not driving one.

The U.S. Department of Energy’s (DOE) recent decisions about how to fund fuel cell research, he says, are putting the country at risk of falling behind in the development and implementation of the most efficient means of converting fuel to electricity. Fuel cells have up to three times the efficiency of an internal combustion engine.

“There is a problem in the perception of the public and policy makers, and in the funding of our fuel cell programs, that hydrogen and fuel cells are linked,” says Wachsman, a faculty member at the university’s A. James Clark School of Engineering. “Hydrogen-based fuel cells are the technology that has gotten all of the press and as a result we’re still waiting for a future hydrogen infrastructure. Yes, fuel cells can run off hydrogen, but they don’t have to.”

Another problem, Wachsman says, is America’s fixation on vehicles. “It will take decades to create a nationwide hydrogen distribution and storage system, and to convert every gas station into a hydrogen filling station. That reality has turned fuel cells into a ‘future technology’ and has resulted in a drastic reduction in the funding of fuel cell research by the DOE in favor of developing electric cars, when in fact fuel cells can be used right now in many stationary and mobile applications, including centralized power distribution and power generation for homes, businesses, and industry.”

Most people are unaware that there are two kinds of fuel cells. The one in the public eye, the proton exchange membrane (PEM) fuel cell, uses hydrogen to generate power. The type of fuel cell Wachsman and his colleagues have worked to perfect, the solid oxide fuel cell (SOFC), has a distinct advantage over its PEM-based sibling.

“Solid oxide fuel cells are unique because they can oxidize any fuel,” Wachsman explains. “They can run off of gasoline, diesel and natural gas today, and biofuels and hydrogen in the future, whenever that infrastructure is in place.”

Hot Technology

Still, nothing’s perfect, and Wachsman can sum up the reason why SOFCs aren’t in large-scale production in a word: temperature.

“That is the issue,” he explains. “It’s the reason why the automotive companies are using PEM fuel cells. PEM fuel cells operate at around 80 degrees Celsius [180 degrees Fahrenheit], which allows them to startup fairly quickly. Current solid oxide fuel cells currently operate at 800 degrees Celsius [1500 degrees Fahrenheit], so it takes a long time to warm up to operating temperature, making them more applicable to stationary power generation.”

Wachsman and his colleagues are working to change that.  In the November 18 issue of Science, the team outlines the technology behind a new world record power density SOFC that generates two watts of power per square centimeter at 650 degrees Celsius [1200 degrees Fahrenheit]. The cell uses a bi-layer electrolyte developed by Wachsman that is more than 100 times more conductive than the conventional zirconia-based electrolyte operating at the same temperature–also a world record. When the cells are assembled into a stack they should produce three kilowatts of electricity per kilogram of material, more than an internal combustion engine at approximately one-third the size.

The paper lays out a strategy to further lower temperature. The team believes its improvements to SOFC electrolytes and nanostructured-electrode designs could ultimately reduce the cells’ operating temperature to only 350 degrees Celsius [660 degrees Fahrenheit]. At that temperature they could start up fast enough for automotive applications, and would be more efficient and more affordable than current SOFCs because they could be manufactured from less expensive materials.

Progress At Risk

The DOE’s 2012 budget request, however, does not include funding for the SOFC program, effectively eliminating it from the agency’s research priorities and greatly reducing funding options for groups like Wachsman’s. This decision, he believes, was made without a complete understanding of recent significant advances in SOFC technology such as those described in the Science paper, which, combined with their fuel-flexibility, put them in an ideal position to improve nationwide energy efficiency today.

In the current issue of Energy and Environmental Science, Wachsman and his colleagues, Craig A. Marlowe and Kang Taek Lee, make the case that SOFCs should be an integral part of our energy policy. SOFCs, they argue, meet all of the DOE’s six key energy strategies: they deploy clean electricity, make use of alternative fuels, help modernize the power grid, will help gradually electrify the vehicles we drive, increase vehicle fuel efficiency, and increase building and industrial efficiency.(1)

“We don’t have to wait for hydrogen,” says Wachsman. “SOFCs represent a solution for everything that you can think of in terms of producing electricity and power today.”

(1) Department of Energy Quadrennial Technology Review Framing Document, U.S. Department of Energy, 2011.

For More Information:

See Eric D. Wachsman and Kang Taek Lee. “Lowering the Temperature of Solid Oxide Fuel Cells.” Science, 2011, 334(6058), 935. View the abstract online »

See Eric D. Wachsman, Craig A. Marlowe and Kang Taek Lee. “Role of solid oxide fuel cells in a balanced energy strategy.” Energy and Environmental Science, 2011. Read the advance article online at: http://xlink.rsc.org/?doi=C1EE02445K.

Visit the University of Maryland Energy Research Center web site at www.energy.umd.edu.

About the University of Maryland Energy Research Center

Located on University of Maryland campus in College Park, Md., the University of Maryland Energy Research Center (UMERC) is dedicated to developing and educating the public about efficient and environmentally sustainable technologies for alternative energy generation and storage. UMERC is administered by the A. James Clark School of Engineering, and includes faculty from all Clark School departments, as well as from the College of Agriculture and Natural Resources, the College of Computer, Mathematical and Natural Sciences, the School of Public Policy, and the College of Behavioral and Social Sciences. With faculty expertise in both energy technology and policy, UMERC provides the research and data to inform the larger policy debate on urgent, global sustainable energy and environmental issues, and the capabilities necessary to establish the State of Maryland as a leader in sustainable energy.

Washington, D.C.–  Senators Joseph Lieberman (I-CT), Richard Blumenthal (D-CT), and Representative Rosa DeLauro (CT-4) today announced $5,702,298 for a Stationary Fuel Cell for the Connecticut Transit New Haven Division Bus Maintenance Facility. The grant was awarded through a competitive program that is part of the Transit Investments for Greenhouse Gas and Energy Reduction (TIGGER) Program.

“Upgrading the maintenance facility with fuel cell technology is another step in the right direction for Connecticut’s transportation sector,” Senator Lieberman said. “This grant will help modernize our infrastructure and recognizes that the way forward lies in clean, efficient, and affordable energy alternatives.”

“This grant is a great investment, recognizing the enormous potential of fuel cells as a reliable, affordable power source,” said Senator Blumenthal. “The funding will upgrade our bus facilities and keep them running effectively so that Connecticut residents and commuters can travel safely and swiftly.

“I am very pleased that New Haven has been awarded this grant, which will help to improve our local transportation system, enable our residents to reach their destinations more efficiently, and lessen the impact on our environment,” said Congresswoman DeLauro. “Fuel cell technology is part of the future of public transportation, and I am proud that Connecticut is moving forward as a leader in its development.”

The TIGGER Program is administered by the Federal Transit Administration and works with public transportation agencies to reduce greenhouse gas emissions and encourage more efficient energy use within local transit networks.

Toyota Motor Corp. Asia’s biggest carmaker, will hold the world premier of  a hydrogen-fueled sedan at the Tokyo Motor Show next month. Toyota plans to market the vehicle in 2015.

FCV-R (world premiere)
A practical sedan-type next-generation fuel-cell concept vehicle fueled by hydrogen, a promising source of CO2 emission-free energy that can be produced from a variety of sources and can be easily stored and transported.  This concept model is a highly practical fuel-cell vehicle (FCV) that is planned for launch in about 2015.

With the fuel-cell unit located beneath the specially designed body, the vehicle can accommodate up to four passengers and boasts impressive luggage space.  The fuel cell stack, consisting of a 70 MPa high-pressure hydrogen tank, has been improved to provide a cruising distance of approximately 700 km or more (under the JC08 test cycle; according to TMC).

ITM Power (AIM: ITM), the energy storage and clean fuel company, notes the following with respect to developments in Germany.

At the National Innovation Programme (NIP) AGM held in Berlin last week, the organisation charged with managing the federal Government’s €700m contribution to its total budget of €1.4bn, the National Organisation for Hydrogen and Fuel Cell Technologies (NOW), noted, that so far, it has issued subsidies of approximately €393m to support the development of the technology. Some €216m, or 55% of the total, has been spent on transport, which includes hydrogen production and infrastructure. Indeed, in its latest review, released last week, the NOW has increased the profile of ‘Hydrogen Production and Delivery’ to an independent category. This follows the launch in May of this year of a separate and additional Federal funding initiative of €200m exclusively for energy storage, which in turn followed the Government’s decision to abandon nuclear power. This decision has promoted green hydrogen to the top of the agenda, as a necessary adjunct to the expanding renewable share of electricity generation.

In its German press release issued on 7 November, the NIP commented “Climate policy goals can only be achieved if efficient drive systems and emission-free fuel is deployed in the transport sector, and highly energy efficient equipment is used in the stationary sector. In order to generate major cost and efficiency savings, current mobility and energysupply solutions will in future be supplemented with products based on hydrogen and fuel cell technology.”

Dr. Klaus Bonhoff, NOW’s MD noted that: “Hydrogen and fuel cell technologies are gaining momentum. This is due not least to the central role attributed to storing energy generated from renewable sources in the form of hydrogen. In the future, hydrogen will be one of a number of emission-free transport fuels, given the fact that the step by step reconstruction of the transport sector has already begun. Fuel cells will not only be used in combination with hydrogen in the transport sector, but in the coming years, together with natural gas, fuel cells will also provide a highly efficient solution for the stationary sector. Even, in niche markets such as the protection of critical infrastructure, for example, in telecommunications, fuel cells as off-grid systems are becoming ever more attractive.”

It is worth noting that the Federal subsidies mentioned above, totaling some €900m, which will be matched by industry, do not include the substantial financial support offered at the state level, not only in halting the deindustrialisation of the former East German states, but also in industrialised states of the former West Germany in an attempt to ensure they have a role to play in the emerging German and European renewable economy.

Phil Doran, Managing Director of ITM Power GmbH commented: “While Germany has more than proved its metal in the field of clean technology developments, which has earned it global recognition, the decision to abandon nuclear power has given added impetus to the renewable cause in general and green hydrogen and fuel cells in particular. It is difficult to convey the seriousness with which Germany is pursuing its goals, in the full knowledge that it is creating a set of industries which will ensure its manufacturing status and export capacity is maintained well into the 21st century”.

Superior Hybrid Power System for Unmanned Undersea Vehicle (UUV) Applications

With the increasing energy demands of the 21^st century creating a pressing interest in alternative power sources, the demand for high performing, state-of-the-art fuel cells has never been greater. However, these fuel cells require the precious metal platinum to generate their high power output, and this drawback has led scientists in Taiwan to develop a competitive replacement by combining carbon, and curiously, vitamin B₁₂.

‘The limited abundance of platinum and other noble metals on Earth restricts the development of fuel cells. Searching for a non-noble-metal catalyst is a major issue,’ explains Kuei-Hsien Chen, from the Institute of Atomic and Molecular Science, Taipei, who, along with other colleagues, has developed this peculiar solution.

In order to generate electricity, most modern fuel cell devices require an oxygen reduction reaction (ORR) at the cathode of the cell, whilst simultaneously, another chemical (often hydrogen) is oxidised at the anode. This redox reaction for power generation has been limited by the slow ORR process, which in nature requires complex enzymes to proceed at any meaningful rate.

Although scientists have been investigating methods for speeding up the ORR, it has been notoriously difficult to produce a cathode that can achieve this and so they have had to resort to loading high amounts of expensive platinum onto the cathode to generate the required ORR rate. 

However, Chen and co-workers have dispensed with the need for platinum altogether, by using cheap carbon that has vitamin B₁₂ dispersed throughout, to form the cathode of their polymer electrolyte fuel cell (PEFC). The performance of this cathode doesn’t quite match that of platinum based cathodes, but at a fraction of the cost, this cathode could open up real opportunities for the practical application of these fuel cells.

Fuel cell expert John Varcoe, from the University of Surrey, UK, thinks that Chen’s advance clearly shows ‘promise for use as a fuel cell catalyst’, however, he urges caution by noting that the fuel cell’s performance over ‘many thousands of hours will need to be demonstrated before it will rival current (more expensive) fuel cell catalysts’.

Chen hopes to continue to develop his PEFC to make the cathode more effective, but in the meantime, this research may make fuel cells more accessible as a power source for the world’s future energy needs.

Ross McLaren