Kicking the oil habit

Can the U.S. cure its addiction to oil? To help wean the country from its petroleum habit, UC Irvine researchers have been working to find viable sources of alternative energy – from deep in the earth to the sun.

Here, researchers Scott Samuelsen, Reg Penner and Derek Dunn-Rankin discuss their work on transforming solar power, fuel cells and coal into low-cost energy sources for the future.

SCOTT SAMUELSEN: FUELING THE HYDROGEN HIGHWAY

Scott Samuelsen is UCI’s go-to guy on fuel cell and hydrogen technology.

Samuelsen led the development of UCI’s hydrogen fueling station, the most technologically advanced, publicly accessible station in the world. It was the first of its kind in Orange County and is a key component of the California Hydrogen Highway Network. The station can fuel up to 10 vehicles per day, and is regularly used by drivers of vehicles manufactured by General Motors, Toyota, Honda, Hyundai and Daimler. The vehicles are not yet commercially available.

Hydrogen is very climate-conscious. When used to deliver energy, hydrogen produces zero or very low emissions. Emissions from a hydrogen fuel cell-powered vehicle contain only water vapor. Hydrogen is produced efficiently from natural gas and can be produced from non-petroleum sources, potentially reducing our dependence on petroleum. The goal is to produce hydrogen through a variety of clean and renewable energy sources.

Samuelsen directs the Advanced Power and Energy Program, which encompasses the National Fuel Cell Research Center, the UCI Combustion Lab and the Pacific Rim Consortium on Energy, Combustion, and the Environment. His research focuses on energy generation, distribution and utilization, and it includes the production of electricity, motive power and propulsive power from fuel cells, gas turbines and hybrids of both.

In this video, Samuelsen explains UCI’s hydrogen research program, the hydrogen fueling station and why hydrogen is the fuel of the future.

— Jennifer Fitzenberger, University Communications

REG PENNER: POWERED BY THE SUN

UC Irvine scientists believe sunlight is the fuel of the future.

UCI launched its Center for Solar Energy in 2007 with a $3.9 million gift from the California Community Foundation. The center, in the School of Physical Sciences, blends biology, chemistry, physics and engineering to find new, better ways to turn solar energy into useable chemical and electrical energy.

Chemists Reg Penner, John Hemminger, Matt Law and Alan Heyduk are leading UCI’s solar energy research efforts. Penner, center director and chemistry professor, discusses solar energy and how UCI is making an impact:

Q: What is the potential of solar energy, given society’s wish to conserve?

A: The amount of energy supplied to the Earth from the sun is astronomical, exceeding the energy consumed by humans over an entire year in just one hour. This inexhaustible energy source is all around us, but it’s expensive to harness, so we use very little of it. For solar energy to compete with fossil fuel-based power, genuine breakthroughs in how we convert solar energy into electricity must occur.

Q: How is UCI contributing to this effort with the Center for Solar Energy?

A: The center looks for bottlenecks in the fundamental science underlying emerging technologies such as solar-thermal, solar cells and the catalysis of photochemical water splitting. Ideas under investigation by center scientists include:

• Designing molecules to absorb light and, using its energy, disassembling water into hydrogen and oxygen gas
• Creating efficient solar cells from earth-abundant, nontoxic and environmentally friendly materials, including metal oxide particles and plastics
• Harnessing the sun’s heat to directly generate electrical power using materials called thermoelectrics
• Using nanoparticles to focus and concentrate sunlight, increasing the efficiency of photovoltaics

Q: What’s unique about UCI’s solar energy program?

A: We work on the first step of the product development cycle. Our scientists focus exclusively on fundamental science. We’re discovering ways to make materials that can more efficiently collect sunlight and convert it to useable energy. When our discoveries are processed by engineers, the result will be the next generation of cheaper, more efficient solar panels.

Q: What are your hopes for the future of solar energy?

A: Our objective is for all types of alternative energy sources to replace fossil fuel-fired power by 2050. Solar energy will need to play the leading role to achieve this ambitious goal.

— Jennifer Fitzenberger, University Communications

DEREK DUNN-RANKIN: ENGINEERING COAL POWER

Coal is readily available and widely used as fuel, but its environmental drawbacks are driving scientists to look for cleaner, more efficient ways to harvest its energy. Derek Dunn-Rankin, mechanical and aerospace engineering professor, discusses coal energy and research under way at UCI.

Q: Coal has been used for energy for a long time. What makes it appealing as a source of energy today?

A: It’s not that coal is an appealing source of energy; it’s simply an available and heavily used source of energy and therefore an important energy security fuel for the U.S. As such, it will almost certainly continue to be used, since energy is required for all economic activity. I am nearly certain that we – or someone else – will burn coal as long as the return on investment is good. So it’s critical to develop methods for maximizing efficiency while minimizing environmental impact when using this fuel.

Q: What are the biggest challenges to using this type of energy?

A: Emissions from coal combustion contribute significantly to increases in atmospheric carbon dioxide concentrations. Efforts are under way to capture and store carbon dioxide from coal-fired boilers, but any dramatic greenhouse gas-limited, coal-fired power plant is at least a decade away. In the meantime, operational adjustments and retrofits to existing boiler designs are important to improve efficiency. New pollution control technologies can reduce emissions, and systems integration and control strategies can lead to performance gains.

Q: What research is your group undertaking to help address some of these issues?

A: We have a number of research activities supported by the Electric Power Research Institute, General Electric/Energy and Environmental Research Corporation, and the UC Discovery Program. Power plants lose efficiency when their air heaters become plugged up or when they are shut down for cleaning. We’re studying ways to minimize those losses. We also are looking for a fundamental understanding of processes that will make it possible to design and predict the performance of power plant boilers despite changes in fuel type and structure.

We’re developing simulations and experiments to accurately predict residual carbon in ash, because this can mean the difference between ash that is reusable for building materials and ash that must be sent to landfills. We also are developing models for predicting mercury capture in exhaust gas to prevent release of this toxic metal. And, we are investigating combustion technologies to prevent excessive emissions and poor efficiency caused by unexpected behavior.

— Jason Mednick, University Communications

Originally published in Vol. 1, Iss. 2 of ZotZine