Energy is vital to dynamic societies and healthy economies. Consider the effects of the August 14, 2003, blackout, the largest in the history of North America. Within 15 minutes of the initial outage, five power grids and more than 50 million people — from southeastern Michigan through Ontario and from northern Ohio to New York City — were in the dark. Many were without power for three days.

This was not an isolated incident; the power problem is a global one. In June 2003 Italian electricity firms ordered the first nationwide power cuts in more than 20 years. A year later China faced one of its most severe power shortages since the 1980s. In fact, several provinces imposed brownouts in an attempt to conserve energy. For the last several years Scottish and British officials have been warning that, without a significant investment to build power supplies and infrastructure, blackouts similar to the August 14 event could occur in their countries.

In the United States as politicians and power companies struggle with technical concerns, consumer confidence, and ethical issues — such as the roles of managers and regulators in the power industry — researchers in the Notre Dame Energy Center are studying cost-effective ways to produce clean, safe, and renewable energy, in order to lessen the country’s dependence on foreign oil and other fossil fuels and reduce greenhouse gas emissions.

The energy center was established in November 2005 to develop new energy technologies. According to Center Director Joan F. Brennecke, the Keating-Crawford Professor of Chemical and Biomolecular Engineering, the center also hopes to play a key role in energy education and literacy, the development of energy policy, and the exploration of the ethical implications associated with energy. Notre Dame researchers have a proven track record in energy related research, but with the creation of the center, they join many universities across the country actively pursuing clean energy technologies. “It is such a huge challenge,” says Brennecke, “that we cannot afford to have just one place working on it.

We need the full force of our scientific and engineering expertise focused on this issue.”At the same time, Brennecke stresses that the energy center cannot physically tackle all of the challenges associated with energy. Instead, the center will target five areas in which University researchers have expertise: energy efficiency; clean coal utilization; carbon dioxide (CO2) separation, storage, and usage; safe nuclear waste storage; and renewable energy sources.



The concept of being more efficient with energy sounds simple. After all, choosing an energy efficient light bulb for a floor lamp isn’t exactly rocket science. But for those interested in conserving energy, it’s as important as turning down the temperature of a water heater, upgrading leaky windows, insulating hot water pipes, or driving a hybrid vehicle. These and other “mundane” actions may seem insignificant when considering the global energy picture, but a commitment to using energy wisely while developing advances in energy efficiency, and other viable energy technologies, is vital in both the short- and long-term.

It is especially important if governments, industries, or consumers think they can rely indefinitely on fossil fuel reserves. According to Brennecke, if the usage of fossil fuels were to remain constant (zero population growth with no increases in usage), oil supplies would last for approximately 35 years, natural gas for 60, and coal for 400.

Engineers at Notre Dame and around the world have been looking for ways to extend fuel reserves by developing more efficient ways of generating power. For example, fuel cells, which function like batteries, are inherently more efficient than combustion power cycles and can generate electricity up to two times more efficiently than a traditional power plant. Unfortunately, because most fuel cells use platinum and other expensive catalysts, they are not cost competitive. Durability is another issue. Fuel cell systems need to be as robust and reliable as combustion engines to be effective.

In projects supported by the U.S. Army and the Indiana 21st Century Research and Technology Fund, College of Engineering researchers are targeting new and less expensive materials for methanol (direct methanol) and hydrogen (polymer electrolyte membrane/ PEM) fuel cells. By changing the flow patterns within a PEM fuel cell (the units most often used in vehicles), they have already achieved a dramatic increase in the efficiency of a cell.

University researchers working in conjunction with the Department of Energy are also attempting to capture the unused heat generated from power generation systems (industrial cycles) and use it to provide energy efficient absorption refrigeration.

A complex chemical substance, coal contains carbon, hydrogen, and oxygen, but it can also contain small amounts of nitrogen and sulfur, as well as heavy metals like mercury. There are four types of coal: anthracite, also called hard coal, which has the highest heating value; bituminous, or soft coal, used mostly for electric power generation; subbituminous, used for generating electricity and process heat; and lignite, which has a high moisture content and low heating value. Lignite is also used to generate electricity.

Coal has played a huge role in the development of the U.S. In the 1300s the Hopi Indians used coal for cooking, heating, and firing pottery. The first commercial mining of coal occurred in Virginia in the 1740s. In the early 1800s it was used to make glass and replaced wood as the fuel of choice for the first commercially practical American-built locomotive, the Tom Thumb.

Produced at one time or another in nearly all of the states that have deposits, coal has been used for domestic heating, railroad fuel, iron smelting, and electricity. Today, more than 20 percent of all of the energy consumed in the U.S. (and more than half of all of the electricity) is produced by coal. It is by far one of the country’s most abundant sources of fossil fuel, and the stage is set for it to once again power the economy.

In order to better address concerns about gases produced from burning coal, researchers in the energy center are studying hydrogen-oxygen combustion and the catalytic conversion of environmentally undesirable by-products of combustion, such as nitrogen oxides (NOx) and sulfur dioxide (SO2). Sometimes seen as a reddish-brown layer of air above urban areas, NOx contributes to the formation of acid rain and nutrient overload that can deteriorate water quality. A significant contribution to acid rain is also made by emissions of SO2.



Researchers are also exploring ways to capture and store the CO2 produced when coal and other fossil fuels are burned, instead of releasing it into the atmosphere. One of the most promising processes involves the use of ionic liquids for flue gas and coal gasification separations.

Ionic liquids, organic salts that are liquid at room temperature, easily absorb a variety of gases. Researchers at Notre Dame have pioneered a technique using ionic liquids to separate CO2 from the flue gas discharged by conventional power plants. The process is especially important to reducing greenhouse gas emissions that contribute to global warming.

According to the National Snow and Ice Data Center, summer ice covering the Arctic Ocean shrank to its smallest size in more than a century. The decades-long shift in ice cover is difficult to explain without accepting, at least in part, man’s impact upon the environment. An increase in CO2 concentrations in the atmosphere has also occurred since the onset of industrialization. Today, CO2 concentrations have reached approximately 380 parts per million, a number that’s expected to rise to 500 or more parts per million by 2050.

Current technologies for separating CO2 do so at a 30 percent energy penalty, meaning that 30 percent of the energy generated is lost in the separation process. The Notre Dame method offers the potential to significantly reduce this penalty and has garnered considerable national attention. Funding for ionic liquids research at Notre Dame over the last five years has exceeded $5 million.



Nuclear power does not rely on fossil fuels and creates no greenhouse gases that need to be sequestered. Yet nuclear power produces only 20 percent of the nation’s electricity. While countries like France and Japan have embraced nuclear power, the U.S. has been reluctant to build more nuclear power plants.

Part of President Bush’s Advanced Energy Initiative, the Global Nuclear Energy Partnership teams the U.S. with supplier and user nations. Its goals include development of a new generation of power plants; new technologies that would recycle spent fuel, reducing the volume of waste that would need to be stored in a geological repository; new small-scale reactors for developing countries; and enhanced safeguards that would make it more difficult to “divert nuclear materials or modify systems without immediate detection.”

The biggest problem with nuclear fission is what to do with the radioactive waste. Where should it be stored? How should it be stored? And, how long can it be safely stored before leaching into the environment?

Notre Dame researchers, supported by a grant from the National Science Foundation, have pioneered the identification of new compounds of uranium and other radioactive nuclides, which will help them predict the mobility of these compounds in the environment. Working with the Department of Energy, they are also studying how radioactive materials would act in a geological repository, such as the Yucca Mountain facility.



Can energy supplies from clean coal technologies or nuclear power meet the needs of a growing population? Or are other solutions needed? From 1900 to 2006, the world’s population more than quadrupled. During the same time period, energy consumption increased more than 16-fold. Today, there are 6.5 billion people who need energy to survive. By 2050, there may be 10 billion demanding their piece of the energy pie, except they will have fewer resources from which to draw.

The options open to them will likely be a combination of carbon-neutral energy (clean coal technologies if commercially viable), nuclear power (which, if used to address the entire projected need, would require the construction of a new nuclear power plant every day for the next 50 years), and renewable energy sources, such as hydropower, geothermal power, wind, biomass, and solar energy. Unlike fossil fuels, renewable energy sources never run out.

Accounting for 20 percent of the world’s electricity, hydropower depends on the volumetric flow of the water and the height from which it descends. One of the main advantages of hydrosystems is that they do not require fuel. Without a doubt the most identifiable source of hydroelectric power in North America is Niagara Falls. In 1893 water was first diverted from the Canadian side of the falls to generate electricity, and a 2,200 kilowatt plant was built just above the Horseshoe Falls. Today, approximately 2 million kilowatts of electricity are generated from a number of sites along the Canadian side of the falls. On the American side, additional power plants generate more than 2.4 million kilowatts.

The world’s largest producer of hydropower, Canada generates more than 70 percent of its electricity from hydroelectric sources. Austria produces 67 percent, Iceland produces 83 percent, and Norway produces virtually all of its electricity using hydrosystems.

Another source of renewable energy is geothermal power. The world’s first geothermal power plant was built in Larderello, Italy, in 1911. It remained the only industrial producer of geothermal power until 1958. Today, Larderello produces 10 percent of the world’s supply of geothermal electricity, powering a million households. Although global geothermal production has doubled in the last 20 years, geothermal power trails hydropower production. It is also not a viable option in many parts of the world, as not all geothermal areas have a high enough temperature to produce steam.

According to the Global Wind Energy Council, the global wind power market increased more than 40 percent in 2005. Almost 25 percent of the new wind capacity was added in North America, making it one of the world’s foremost implementers of wind power. In fact, the Statue of Liberty and Ellis Island are powered totally by wind energy.

Like other renewables, wind lessens dependence on fossil fuels, such as coal and natural gas, provides clean energy, and has the potential to support additional economic development. The wind turbines, which can stand alone or connect to a utility grid, operate up to 100 meters above the ground, where they intercept faster, less turbulent air. When operating at peak power, wind farms in the U.S. are expected to generate 25 billion kilowatt-hours of electricity in 2006.

Biomass fuels (energy stored in organic matter) provide three percent of all of the energy consumed in the U.S. and produce 9 percent of the world’s energy needs. Wood, agricultural waste, municipal solid waste, sugar or starch crops, grass straw, soy beans, and waste vegetable oil are all sources for biomass fuels, which can be converted to liquid fuels, such as methanol and ethanol, as well as to heat and electricity. Although a subject of great debate regarding the specific percentages involved, it may take almost as much energy (most likely in the form of fossil fuel) to produce one liter of biomass fuel as is obtained from burning one liter of the fuel. Currently, only the sugar/carbohydrate content of plants is used to produce biomass fuels; the higher the sugar/carbohydrate content, the larger the ratio between the energy produced and the energy consumed. So while this renewable energy source appears to be a promising alternative to gasoline, there are many aspects in need of further research — such as using the whole plant, including its cellulose, or developing crops specifically for use in biomass fuels — before these types of fuels are commercially viable.

Solar power can be used for heating and to produce electricity. In the simplest of terms, a solar cell converts light from the sun into electricity. A photovoltaic cell is composed of a semiconductor material that absorbs visible light and converts the incident light into electricity. Though a clean and sustainable source of energy, photovoltaic cells are not currently competitive when compared to other options. However, the decreasing cost of production and increasing demand for clean energy are likely to make photovoltaics a viable option in the future.
University researchers are working to reconfigure photovoltaic cells using nanomaterials. In particular, they are studying means by which cells and photocatalytic processes can be made more efficient and less costly through the use of nanoparticles and hybrid inorganic-organic materials.