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The spheres in this computer model of a molecular bearing each represent a single atom. Structures like this can be built with carbon compounds and used to create tiny machines, revolutionizing fields like medicine and computer chip manufacturing.
BY ONE MEASURE, nanotechnology is the science of very small stuff. Scientific work in the field takes place at the scale of the nanometer, which is one billionth of a meter, or about 10 times the size of an atom, and 10,000 times smaller than the width of a human hair.
There's much more to the science, however, than mapping the miniature. Many would agree that nanotechnology involves the creation of functional materials and devices through the manipulation of nanoscale matter. The science tries to exploit and harness novel properties that exist at that scale.
For the electricity sector, the science could prolong the life of powerplant equipment and give operators constant data about what's going on within the system, leading to greater efficiencies. Nanotechnology also has significant bearing on the transmission grid: Nanosensors on transmission lines could help quickly identify problems and determine their scope-and help keep them from spreading. (See the sidebar, "The Smart Grid.") New nanotechnology- based materials also may make powerlines much stronger and lighter.
Among other things, scientists are discovering that if they arrange matter on the nanometer scale, they can customize fundamental properties of materials, like conductivity or melting temperature, without transforming the material itself.
Above: Just 10 atoms wide, these nanowires could be used in computers operating at the limits of miniaturization, or to build extrastrong power lines. They are made from rare earth suicide, in this case, a compound containing lanthanide and silicon. Right: Water droplets form on a piece of Kevlar fabric treated with a nanoscale, water-resistant coating only a few nanometers thick.
In the short-term, says Mark Modzelewski, executive director of the NanoBusiness Alliance, the nanotechnology industry's trade association, this science of small things will help structures already in place. It will reinforce lines, strengthening them and helping them retain greater conductivity. It will be used in lubricants for machinery like windpower turbines, to make the various power units stronger, more insulated, and more efficient. "Long-term," he says, "the sky's the limit in the sense of using everything from carbon nanotubes for hydrogen storage to creating new battery power to using quantum dot structures to take the place of light emitting diodes."
No doubt, nanotechnology is the thing right now. Work in the field is going on at university, government, and corporate laboratories around the world. Much of this activity is because of the National Nanotechnology Initiative (NNI), launched in 2000 by then President Clinton. NNI aimed to organize under one roof the disparate nanotechnology research areas in which the federal government was engaged, and it boosted funding. In 2000, federal nanotechnology funding was about $200 million. Now, it's closer to $1 billion, and Congress is wrestling with a bill to make NNI a permanent part of the federal bureaucracy, with its own staff and budget. Foreign governments followed NNI's lead, turning nanotechnology research and development (R&D) into the subject of a worldwide race for supremacy. The United States was, by far, the industry leader in 2000, but Europe and Asia are catching up fast. The Japanese government, for example, now spends more on nanotechnology R&D than the U.S.
As government leaders wrestle with policy and funding, venture capitalists invest in nanotechnology start-ups, and corporations telescope resources around different nanotechnology projects, the science is progressing faster than its evangelists would have predicted even two years ago.
Sensing Sparks For the electricity industry, there are several areas where nanotechnology R&D will make a difference. Nanotechnology-laden sensors will let powerplants monitor pollution much more effectively. Household machines and power systems will be able to communicate about power needs and prices, and next-generation fuel cells, dependent on nanotechnology research and development, will be key to improving distributed generation systems.
But it's already at work in a number of applications. Nanotechnology has made solar cells cheaper, more flexible, and potentially ubiquitous. Nanocoatings are making generators and turbines sturdier, giving them longer lives and saving power companies money.
Overall, the electric power industry does not spend much on nanotechnology R&D, experts say, and its dance with the field is not as high-profile or energetic as the semiconductor or biomedical industries. Compared to most industries, however, electric power companies aren't doing so badly.
"It's the same in any industry," said Pradeep Haldar, a director of the Energy and Environmental Technology Application Center and professor at the University of New York-Albany. "People are trying to figure out how they can apply nanotechnology to an effective business environment. Long term, I think it will have a huge impact on the energy area."
Ant pad. This electronic micrograph shows an ant approaching a pressure sensor's sensing mechanism (circular area). Though the power industry already uses sensors, miniaturization will make them cheaper and more efficient.
The application of spark sensors at a transformer substation could help identify sparks and stop fires and outages.
Still, for the industry to really embrace nanotechnology, the field is going to have to prove itself first. "The utility industry is conservative," said Haldar, who spends much of his time working with energy companies. "Unless you can show them in a reliable way that a piece of equipment works and runs properly, they will not jeopardize introducing it into their system. There has to be a paradigm shift in their minds."
The industry has been using microsensors even before the term "nanotechnology" emerged, but future sensors will hinge upon the miniaturization that nanotechnology can deliver. Some current microsensor devices-used to measure displacement, force, pressure, acceleration, temperature, optical radiation, nuclear radiation, and other physical parameters-are the size of cigarette packs, much larger than nanoscale. But the guts of the sensors will increasingly depend on nanotechnology advancements.
About three years ago, Public Service Enterprise Group (PSEG) in New Jersey began working with microsensors. "The science was there, the technology was developing, and we said, 'We have to look at this, something is going to happen soon'," said Harry Roman, a PSEG technology development and transfer consultant.
The company formed a partnership with the New Jersey Institute of Technology, and together they started working on a problem they thought could be solved with sensors: The company wanted to hear sparks as they occurred in transformers. Sparks can cause transformers to fail, and a failure can put a transformer out of commission for months. Worse, sparks sometimes cause fires, threatening entire power stations.
"You could lose half your station," Roman said. "You need to understand what is happening. You want to be able to say, 'Guys, shut it down. Let's take a look and see what is going on'."
So far, the partnership has led to the development of a first- generation sensor that is placed directly into transformer oil. Roman described it as a probe, or an "ear," sticking in from the side of the transformer. The sensor sits inside the transformer and listens, essentially, for the sounds that sparks make and then alerts operators as the sparks happen. When the research team began to explore the idea, no one knew what transformer sparks sounded like, so it took a lot of experimentation to identify the right sounds. "We've come a long way during the past few years," he said. "We think we understand better than most people what sound a spark makes under a range of conditions."
The application of spark sensors at a transformer substation could help identify sparks and stop fires and outages.
The partnership is about to unveil a second-generation sensor, which it will test on old transformers. Eventually, the group aims to deploy the sensors in transformers throughout the company. And now, he said, the company's underground cable engineers want a sensor, too, to gauge cable movement: They jostle around quite a bit, and the movement weakens the cables and leads to breaks.
Nanotechnology also is leading to the growth of an entire industry that revolves around using sensors to detect traces of biological or chemical weapons in the atmosphere. A network of security sensors at a powerplant could determine who is entering what door and where, what substances are in the atmosphere in and around the facility, and whether computer hackers or a computer virus is attacking the facility's electronic infrastructure. PSEG also is talking about developing sensors that could be used for security at their power facilities.
The company hopes to develop sensors that would work as a "smart splice" for high-voltage transmission lines. From helicopters, power employees would clamp sensors onto transmission line splices. The sensors feed information about the condition of the splices to plant technicians. In th\eory, they would let them know which splices need to be replaced before they break.
"In the movie Twister, the characters are trying to get the tornado to suck up radio transmitters so they can map the interior of a tornado," Roman said. "That's what we're doing. We're trying to get these sensors distributed around our system so we can know more intelligently what goes on."
The technology could be a huge boon to reliability. "It's like looking at the utility infrastructure as a skeleton and trying to stretch an intelligent skin over it," says Roman. "The nerves are the microsensors. They will be the first line of information to bring the data to us."
Microsensors will play a big role in the future of the electric power industry, but Terry Tyler, a partner with IBM Business Consulting Services, is not entirely sanguine about the degree to which that role will benefit the industry. "I view nanotechnology as a disruptive technology that will turn the whole business model on its ear, in the next decade for sure," he says.
Sensors will make power equipment like generators and transformers intelligent, Tyler says. They will let companies weed out deficiencies and glitches in the system and make them more responsive to customer demands. Companies that don't invest in technology and supercharge their offerings will lose to the competition. "If you can put these intelligent sensors out there monitoring power, you've made outage detection almost immediate," says Tyler. "It saves a lot of money."
Also, consumer appliances like refrigerators and dryers are increasingly wired for the internet. Within the next decade or two, Tyler predicts, appliances will communicate with the electric power system, putting new demands on customers and power generators. Appliance manufacturers and original equipment manufacturers-the people who make the pumps, turbines, and instrument controls, for example-already have started to embed microsensors in their products. But nobody in the energy and utility space, he says, is yet dealing with the machine-to-machine business model of the future, a commercial arena in which a refrigerator, for example, will bargain through a computer network with power-provider databases to arrive upon a precise measure of voltage for the cheapest price. In essence, computers will strike deals with each other.
Each of the colored spheres in this computer graphic of a molecular nanotube represents a single atom: carbon (blue), oxygen (red), and hydrogen (yellow). Nanotubes can be used to make tiny mechanical devices, superconductors, molecular computers, or extremely strong materials.
Environmental Technologies
Another important application for microsensors will be in pollution detection and monitoring, says John Stringer, technical director at the Electric Power Research Institute (EPRI).
"There has been a progressive increase over the years in the amount of pollution that coal-burning power-plants are allowed to emit," he says. "The requirements are sufficiently tight that even measuring emissions is a problem and detecting an upset in a plant is a matter of considerable concern. The result is we are interested in detectors that can tell you in real time what is going on in your plant."
Sensors will likely be the first area of nanotechnology that the industry embraces, according to Arun Mehta, manager of fuels technologies at EPRI. Spangling plants with sensors will not interfere with day-to-day powerplant operations. As opposed to using new nanotechnology materials to replace the steel cores of transmission lines, which would be very costly, risky, and difficult, sensors improve existing performance.
It's important, however, that sensors do more than just send messages, he said. They should be part of a network that can fix itself and make changes on the fly, without human intervention. "The sensor and the system that produces the corrections have to be closely integrated," Mehta said. "The system has to be smarter. In the overall area of transmission, nanotechnology will give us a path to this smartness."
To that end, EPRI and other groups are working with the Consortium for Electric Infrastructure to Support a Digital Society, an advocacy group based in Washington, DC, to help shepherd the industry toward a more aggressive online environment.
Nanotubes: The Basics
Single-wall carbon nanotubes are nanotechnology's building blocks. They are stronger and lighter than steel and are highly conductive-they can conduct electricity as well as gold or copper, have unusually large surface areas, are just a few microns long, and can be strung together into strong, light, conductive ropes. Within the next decade or two, some experts think that power lines could be filled with these nanotube ropes in addition to, and maybe even instead of, steel and aluminum.
In theory at least, nanotubes would be wonderful substitutes for steel and aluminum in powerlines. The problem is that while the technology is there-and this is the problem in so many areas when people speak of modernizing the transmission system-there currently is little manufacturing capability. The nanotech industry is nowhere near being able to produce new power cables to string across the country.
On the other hand, according to Mehta, it's possible that in the near future the companies that manufacture electric powerlines may be able to incorporate carbon nanotubes into their products, thereby enhancing strength and conductivity, while chipping away at weight.
Carbon nanotubes are finding application in fuel cell electrodes- a much cheaper alternative to platinum, the conductor of choice now.
Carbon nanotube-filled lines, too, could work at a higher temperature. Reducing the coefficient of thermal expansion-in the case of powerlines, the degree to which they sag when they are heated-is a primary research interest at EPRI, said Stringer. The sagging, overheated line suspected in August's blackout affecting more than 50 million people comes to mind. "The grid at the moment is limited in many cases by a temperature limitation associated with the sagging on the overhead conductors," said Stringer. "If we can get a better material, something lighter and stronger with good conductivity, we would be able to increase the power-carrying capacity that we can accommodate in our right-of-ways."
Improving fuel cells is another busy area of nanotechnology and nanotube research. Anything that uses copper right now might actually in the future be able to use carbon nanotubes, according to Ken Smith, vice president for technology at Carbon Nanotechnologies in Houston.
In a fuel cell, he said, the electrode portion requires millions of tiny particles, which typically are platinum or some other catalyst, upon the surface of which an electrochemical reaction takes place, where positive or negative charges are separated or joined. Carbon Nanotechnologies has developed fuel cell electrodes using single-wall carbon nanotubes that have upped the current capacity substantially, while also using low amounts of platinum. It's still in the developmental stage, he said.
"A lot of people believe fuel cells, particularly for portable electronics, will see the market in the next few years," he says. "We'd like to see carbon nanotubes in them."
Haldar with SUNY-Albany called the application of nanotechnology developments like single wall carbon nanotubes to fuel cells a "no- brainer" and championed their role in distributed generation. "The trend is toward having your power generation system onsite to provide power, even as base power, and that requires fuel cells."
Making Solar Competitive
Today, solar cells are too expensive and bulky to contribute much to the power supply in the country. Nanosys, one of the larger nanotechnology companies in the industry, wants to change that.
The company is developing a nanocomposite-based material comprised of nanocrystals and a host material that binds it all together, according to Stephen Empedocles, Nanosys's cofounder and director of business development. Each nanocrystal is a solar cell. The composites they are developing incorporate trillions of the cells into a single film, all working in tandem to produce a single, macroscopic solar cell.
But what nanotechnology will bring to the photovoltaic industry, says Empedocles, will not necessarily revolve around improvements in efficiency. "I've heard some people claim they get 70-percent power conversion efficiencies using nanotechnology, and I don't believe that's true," he says. Instead, he thinks nanotechnology will let companies produce solar cells more cheaply and with the pliable characteristics of plastic.
Amorphous silicon solar cells, made of small silicon crystals, are 20 percent less efficient than earlier silicon photovoltaic solar cells (in the background), but they are much cheaper to produce.
Though large-scale production of nano-based products Is years away, some companies are producing high volumes of flexible plastic solar cells. This roll-to-roll process could make the cost of solar power competitive with fossil fuels.
The company recently announced its first corporate partnership, with Matsushita Electric Works in Japan, the largest supplier of photovoltaic building supplies in Asia. The partnership aims to produce roofing shingles with solar energy incorporated into the outer skin, turning roofs into instant power generators. The shingles will offer a 15-percent conversion efficiency, at a cost of less than $1 a kilowatt. Right now, traditional solar power is $4 to $5 a kilowatt. At $1 a kilowatt, it can compete against fossil fuels.
The first market release will occur in Japan, where the production of power by fossil fuels is very expensive. In the United States, Empedocles said, adoption rates will likely vary, depending upon geography. In California, where there is plenty of sun and most houses sprawl on one level-offering a premium of sun-s\plashed surface area-adoption of the solar skins may be rapid. In Boston, which receives less sunlight and where many houses stand two or more stories high, the popularity of the cells may be less marked.
"Our goal is to produce solar materials at a cost comparable to fossil fuels," he says. The market today for solar products stands at about $1 billion. "Solar power is not a cost-effective form of power," says Empedocles. "If you can buy electricity off the grid for five times less than installing solar cells, why wouldn't you? At the end of the day, people want to pay as little money for electricity as they can, and they don't care where it comes from."
Lightweight and flexible polymerbased photovoltaics based on nanotechnology that convert sunlight into electric power are also being developed at Konarka Technologies in Lowell, MA. Konarka's cells use semiconducting nanometer-scale titanium oxide crystals covered with light-absorbing dye. The dye oxidizes, providing electrons enough energy to leave the dye molecules. The electrons then travel through an electrode that powers the device, and then re- enter the cell from a back wire. They are then conducted by an electrolyte solution, regenerating to the dye and completing the electrical circuit.
"What we're doing is liberating an electron from a visible light absorbing metal organic complex, and through cell interconnection regenerating the active species," said Bill Beckenbaugh, president and CEO of Konarka. "We're putting light in and getting current out." One benefit of the Konarka approach: All visible light sources- not just sunlight-can be used to generate power.
The company is applying its technology to low-cost plastic materials, and when the product is in the marketplace, Konarka will focus at first on using the cells for portable power, for "capturing sunlight or internal light and storing the energy for later use by a product, whether it's lighting, electronics, communications equipment, or portable electronics. In all of these products, we see a tremendous future use of lightweight plastic-based photovoltaics."
Bionic man. Konarka uses nanotechnology and conducting polymers to create a source of renewable power that is woven into this soldier's uniform and will power his equipment.
As the technology becomes more mature and efficient, smart power companies will invest in discovering ways to use it to "put power back into the grid," he says.
Now, the industry largely views photoelecticity as "a niche role within the area of distributed generation," said Stringer with EPRI. "Our industry is always interested in the idea of power from the sun," he said. "It's just that it's very difficult to make it cheap enough. If we could persuade the American public to accept the idea of electricity at five times the present price, we could do it now."
Start Thinking
The nanotechnology industry is growing fast, and its advocates champion the science's promise for transforming just about everything, from electronics to materials to medicine. Some companies are developing products that are now entering the marketplace, while the government is paying for the research that, it is hoped, will lead to revolutionary things, like uniforms for soldiers that will create instant tourniquets around injuries. Universities around the country have opened new nanotechnology research labs based on government money. Traditional labs, too, are shifting toward nanotechnology research.
"We believe that nanotechnology has the potential to revolutionize many fields and think it is one of the key areas where we should be investing basic research dollars," said Richard Russell, associate director for technology at the White House Office of Science and Technology Policy. "Nanotechnology holds great promise, and it's worth our investment of time and taxpayer dollars to do research in the field."
The science is "important for understanding the foundation of life, understanding what is common in all disciplines, understanding how to expand the limits of living on earth," said Mihail "Mike" Roco, a National Science Foundation official who started the NNI and who has shouldered much of the responsibility for government involvement with nanotechnology. "It's much broader than just making money."
But it's the money that is getting corporate America behind the science. The electric power industry, like most industries, is just now starting to dabble in the science of small. Nanotechnology could lead to an intelligent grid, more conductive power lines, a sprawl of distributed generation. It could help the industry save money by increasing efficiencies, for example, but it also could give consumers more choice, forcing utilitiess to work harder to get their business.
Researchers at EPRI have recently started to dig into nanotechnology issues. They are researching the scope of academic research and determining what products are available now, or will be in the marketplace in the near future. Most important, they are trying to figure out now which technologies will be useful-or will challenge-the electric power industry in the future.
"There is a lot of interest out there, and there are manufacturers advertising these materials, and this industry as a whole is going to be looking at options for installing new conductors" to replace aging, existing conductors, Stringer said. "What nanotechnology might do is offer some alternatives to the traditional options."
"The electric industry has not started to look at this in a way they should," said Stringer. "In the next few months, that will be our mission-to get them to start thinking."
Left: This tiny microcog could be used in a microscopic sensor, which can detect acceleration, pressure, flow rates, or the presence of certain chemicals. Above: Altering the number of balls (carbon molecules) in this peapod (carbon nanotube) changes the tube's conductive properties.
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