ASU Research E-Magazine: Sun Rise: Avoiding Blackouts and Embracing the Sun

More than 50 million people experienced the discomfort of an electrical blackout on Aug. 14, 2003. Some were stranded in elevators for up to five hours. Some were trapped in subways. Others were simply stuck in the dark for as long as 24 hours without water, refrigerators, or air conditioning.

The largest blackout in North American history affected major cities in New York, New Jersey, Vermont, Michigan, Ohio, Pennsylvania, Connecticut, Massachusetts, as well as in Canada. The culprit was the failure of an interconnecting grid system. That system is responsible for supplying electricity to the northeastern United States and Canada.

Arizona State University researchers suggest that such blackouts could be avoided altogether. Govindasamy Tamizhmani is director of both the Photovoltaic Testing Laboratory (PTL) and Fuel Cell Laboratory (FCL) located on ASU’s East campus. He and his team are actively developing “green” alternative energy resources. Such renewable energy sources could eliminate future power outages. They might also significantly reduce the pollution that is choking Mother Earth.

Researchers at the East campus spend their days partnering with the sun. They also work closely with hydrogen, the universe’s most abundant element. They study the safety and reliability of photovoltaic (solar or PV) modules and work to develop fuel cell energy sources.

“ASU is in a unique position to influence the energy industry,” says Tamizhmani. “We are recognized around the world for our work in the solar energy field. We conduct daily experiments on the emerging field of fuel cell technology. This technology is poised to lead future energy production.”

Hydrogen to the Rescue: Fuel Cell Technology
Fuel cells use hydrogen to produce electrical energy. Fuel cells can provide an uninterrupted back-up power supply, even when power plants fail. A typical hydrogen fuel cell can provide power over many days. Traditional battery-powered back-up systems might supply electricity for only a few extra hours.

A fuel cell’s basic structure consists of an electrolyte (membrane) and two electrodes (positive and negative). The combined Teflon-like plastic membrane and the carbon-platinum electrodes convert hydrogen to electricity as natural gas passes over them.

Fuel cell technology relies on water and natural gas as the two primary sources for hydrogen. Water—H₂O—requires the use of a costly electrolysis unit to break down its two atoms of hydrogen and one atom of oxygen. As a result, water is a less economical option. At ASU’s Fuel Cell Lab, extracting hydrogen from natural gas is the preferred method.

ASU scientists and students build and test new fuel cells. They apply them to existing applications. One student-led project included the creation of a fuel cell-powered uninterruptible power supply (UPS) capable of supporting a computer for up to 192 hours (see sidebar). A standard PC backup battery might last for only an hour.

Fuel cells are created daily in the lab. Each is then routinely tested for performance at different temperatures and pressures, and with different types of fuels. ASU researchers also monitor and test fuel cell systems that supply energy to the public. Bill Shisler and Ha Nguyen are research assistants. They oversee a residential fuel cell system with Arizona energy provider, Salt River Project (SRP).

“Our job is to review the emerging technologies of clients,” Shisler explains. He documents system efficiency and troubleshoots the 5 kilowatt natural gas-powered system that feeds electricity to SRP’s electrical grid.

“We test several parameters,” he says, standing next to the freezer-sized unit that runs 24 hours a day, 7 days a week. “We look at the extreme heat, dust and dirt, power output, efficiency, and water and natural gas consumption.”

To date, the unit has produced more than 226 megawatt hours of electricity since testing began in June 2003. That is enough energy to support a typical Arizona home for two years.

Scientists know that fuel cell-generated electricity is a cleaner and safer alternative to fossil fuel or nuclear power plants. According to Tamizhmani, pollution could be reduced by 50 percent when fuel cell energy sources are utilized. Even in automobiles, fuel-cell powered engines have proven twice as efficient as gasoline engines. They produce the same amount of energy with less carbon dioxide pollution.

Tamizhmani predicts that emerging fuel cell technology also is likely to replace items that operate with traditional batteries. That includes cell phones, laptop computers, and lawnmowers.

The Power of Sunshine: Photovoltaic Energy
Fuel cell research expertise grew from ASU’s reputation as a world leader in photovoltaic (solar) energy research. That reputation expanded dramatically in 1997. ASU’s PV Lab became the first accredited photovoltaic module testing laboratory in the United States. It is one of only three such labs worldwide.

“The accreditation established ASU as a major player in renewable energy research and development,” says Bob Hammond. Now retired, Hammond was hired in 1992 to establish the Photovoltaic Testing Laboratory at ASU.

“Charles Backus was the associate dean of research for engineering at ASU at that time,” Hammond recalls. “He was one of the leading researchers in renewable energy during the 1979s and 1980s. His industry expertise drew the attention of national laboratories. They wanted a U.S.-based PV testing facility.”

Today, the PTL provides long-term outdoor exposure testing services to several manufacturers of solar modules, including Ohio-based First Solar. Their 30-kilowatt system produces electricity from sunlight. That electricity is fed to SRP’s electrical grid, producing enough energy to power six homes.

Lots of work takes place before First Solar’s modules are ever placed among the PTL’s arid outdoor forest of solar panels. First, each module must undergo a battery of tests inside the lab.

Environmental test chambers are designed to simulate a variety of climactic conditions. The walk-in chambers simulate the weather conditions of Alaska, Florida, and even Japan.

Inside the lab, solar panels are pelted by a student-designed, state-of-the-art hail impact tester. The device launches golf-ball-size chunks of ice at speeds in excess of 50 mph.

The panels also undergo a pressure test from another ASU-inspired device. The dynamic load tester applies cyclic pressure and a vacuum on the back side of the module. The idea is to create the same type of force a panel might be subjected to if it were placed in a windy location.

In total, the panels undergo about 230 tests over a period of 90 days. Each test is designed to ensure the safety, durability, reliability, and performance of each module.

“Certification testing is important. It allows buyers to gain confidence in the durability of the PV modules for climatic conditions in the world,” says Tamizhmani. “Solar modules also come with 30-year warranties. We evaluate whether the modules can survive harsh climatic conditions with practically no degradation in performance for up to 15 years and beyond.”

The PTL boasts customers from more than eight countries, including China, Germany, and Japan. It is the only university laboratory in the United States to participate in PV standards development activities.

“As we test panels, we document recurring problems,” explains Tamizhmani. PTL researchers are part of an international standards review committee that includes members of professional societies, PV manufacturers, and government agencies. They share findings, recommend changes to testing methodology, and help to revise international standards for the certification of modules.

“Part of our responsibility as a testing lab—and as a service to the community—is to develop better standards as we learn more,” says Charles Backus, recently retired provost of ASU’s east campus. “By certifying solar products, we’re indicating that they are high quality.”

Indirectly, Backus says this stamp of approval increases buyer confidence and promotes higher sales volumes. Eventually, costs will decrease as the production of solar energy products increases.

Of course, other factors impact the speed with which the public and commercial industries are willing to embrace alternative energy sources. Pollution concerns are one factor. The current high price tag on alternative energy systems is another.

“Exactly how do you measure the financial impact of air pollution?” Backus asks.

If you could measure its impact in dollars, he says, the government might be more compelled to fund alternative energy research in the short-term. Ultimately, this would reduce costs to the consumer.

Today’s fossil fuel power plants produce electricity for about 10 cents per kilowatt hour. Solar electricity doubles in cost.

“With mass production, solar module costs could be reduced drastically,” explains Tamizhmani. “And if fossil fuel costs continue to rise in the United States, PV electricity might quickly become cost competitive.” That trend already is taking place in Europe and Asia, he adds.

While it may seem that solar and fuel cell energy is slow to catch on in the United States, Backus points out that the solar energy industry has steadily grown by 20 percent each year over the past 20 years.

“In another 20 years, imagine the impact such growth would have on society,” he says. “Solar energy will be more accessible and affordable. It will support the long-term health and sustainability of the planet.”

Even now, many scientists are taking note of the benefits of alternative energy. Every kilowatt hour of electricity generated by solar modules reduces greenhouse gas—carbon dioxide pollution—by 662 grams (1.5 pounds).

Today, solar energy is used to pump well water and deliver electricity to remote cabins. It powers interstate highway lighting, emergency telephones, and bus stop stations. It’s also being used more frequently on homes and in office buildings.

“The PV industry has demonstrated itself as long-term, reliable, and safe,” Backus explains. The ASU engineer’s working cattle ranch has been powered solely by solar electricity since the 1970s.

“With increased production, the public will become more aware of solar options. New products will be developed. We are progressing relatively quickly,” he adds.

Tamizhmani compares this growth to that of the computer industry.

“In the information industry, society moved from mainframe computers to desktop computers,” he says. “In the energy generation industry, society is poised to move from centralized power plants to distributed generation.”

Solar and hydrogen energy generation systems, he predicts, are the frontrunners that will provide a cleaner and more efficient energy future.—Melissa Crytzer Fry