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IEEE: The expertise to make smart grid a reality

Interview with Alan Mantooth

Dr. Alan Mantooth is an IEEE Fellow and Director of Standards for the IEEE Power Electronics Society. He is  a distinguished professor of electrical engineering at the University of Arkansas and executive director of three research centers at UA: the NSF center on Grid-Connected Advanced Power Electronic Systems; the NSF Vertically-Integrated Center for Transformative Energy Research; and the National Center for Reliable Electric Power Transmission.

In this interview, Alan Mantooth discusses the role power electronics will have in Smart Grid. He also characterizes the Smart Grid as a "grand challenge" that requires sustained attention and commitment from industry and all stakeholders.

Question: What would you say are the greatest benefits of Smart Grid?

I actually think that the greatest benefit Smart Grid brings to us is balance.

The Smart Grid does this in various ways. It gives us options that we can choose from so that we can deliver the most appropriate energy services to a market depending on the market's local needs and energy resources, such as wind and solar. Smart Grid also allows us to achieve a balance between energy supply options, such as renewables, fossil fuels and nuclear power, because it enables more renewables to come onto the grid in a stable and practical fashion and can actually make money.

Another thing Smart Grid gives us is the opportunity to hold electricity prices down because of improved operational efficiencies. It does this in part by using power electronics devices to facilitate distributed generation. Power electronics devices also perform metering functions and communicate about load factor and other grid conditions; this gives us an ability to observe and react better, which has the potential to introduce additional benefits in a Smart Grid.

Question: Smart Grid will require the introduction of many new technologies to existing grid systems. How will utilities go about incorporating these new technologies?

We have to be careful not to foul this up by trying to do too many things at once. There has to be coordination. I like to say that we're going to have to have an "evolution to a revolution" for Smart Grid because at each stage of development we will have to stop and take stock of what has been accomplished and learn from it before going to the next step.

This is how it has to be done. It is not like introducing a new iPad. We have an installed base and a machine called the grid and it has to continue to operate reliably for Americans. We can't just throw a bunch of new technologies onto it before we understand how each component or service is going to interact with another. We must have demonstration projects. And we must develop best practices from each project that we can study and learn from before we implement each technology in different locales.

Question: As industry evolves to Smart Grid, what are the greatest challenges it will have to deal with?

Let me start by addressing an outward-looking perspective that focuses on the policy and the regulatory environment in which all of this has to occur. I think one of our biggest challenges is maintaining focus as a nation. We can't let Smart Grid become a political football, where it is considered important and worthy of investment one day and unimportant and not worthy of funding the next day. As a nation, we have to understand that the electric grid is our legacy, but it's now over 60 years old. We have to address it now. The question is, can we do this as a people? To me, this is the biggest challenge.

Another perspective looks inward to our community of engineering experts who are doing the technical work that will make Smart Grid possible. There is no question that we have technical challenges to overcome to modernize the grid. We are fortunate that we already have many forums for discussion and debate and for evaluating technical solutions. The best technical solutions will emerge from these debates. These solutions will bring digital age technology and technical innovation to the electric power grid, deliver dramatic improvements in efficiency and help hold equipment costs down. If we just let the industry's innovation engines produce, we are going to see great results.

But if we don't stay the course as a nation and as an industry, we are going to lose out on many of the great innovations that can occur. Our country will become a follower rather than a leader in the field of Smart Grid.

Question: If you could change anything in Smart Grid right now, what would that be and why?

I don't know the answer to this, but I would like to change the way in which we commit to grand challenges in this country.

I would like people to agree that solving our electric power grid modernization problem, as I'll call it, is a grand challenge and that we are going to commit to the challenge and stay the course just as we committed to going to the moon. Funding may go up or down a little bit as we debate and fine tune issues and programs, but overall we should say that we are going to develop these technologies and roll them out because it's what our country needs. I certainly expect oversight; this must be provided when you give money to people to do these things. But politicizing Smart Grid and jerking funds after they've been allocated makes good decisions look bad when very worthwhile projects end up withering on the vine.

Lack of commitment to this challenge also stifles participation. Even companies that have really significant technologies or ideas to offer might think they can't rely on funding or agency support. We can't let this happen.

It doesn't have to be $50 billion a year, either. The government has helped our electronics industry maintain its competitiveness internationally without pouring billions upon billions into that industry's businesses. We just don't hear much about it because it's so successful.

Question: Let's talk about some power electronics technologies that will be used with Smart Grid. What are solid state power transformers and what role will they play?

Most people understand that transformers, whether pad mounted or sitting on a utility pole, basically serve two purposes. One purpose is to electrically isolate one circuit from another through a magnetic medium, and the other purpose is to step the voltage up or down depending on the level of service needed. A solid state power transformer does the same thing, but the beauty of it is that it can do much, much more because it also has a microprocessor and communications capability. For example, a solid state power transformer will be able to communicate instantaneously, at set time intervals or whenever needed, to indicate how the grid is behaving at a specific transformer. It could also perform energy management algorithms for equipment and appliances served by that transformer.

Solid state power transformers will make a tremendous difference in grid performance and energy consumption and they can be controlled and programmed from the central office of a utility. The company will not have to send out a service technician to work on the transformer or reprogram it. The company still might need on-site maintenance from time to time; in fact the solid state power transformer will tell us when maintenance is required. These types of capabilities illustrate how you can more efficiently operate the grid.

Question: What are fault current limiters? How will these serve the grid and why are they important?

A fault current limiter or FCL can be described as a shock absorber for the grid or a surge suppressor for the grid. There are two main types being developed: superconducting and solid-state. An FCL might be installed at a distribution feeder out of a substation or perhaps between two substations, where it can absorb any problems that might occur between the two locations. If a fault occurs on the line, the device can protect everything downstream by simply opening up like a breaker. Or it can be more intelligent and function as a re-closer (at least a solid-state FCL can) and allow power to stay on by absorbing the over-current from the fault. Potentially, the fault will clear in a matter of seconds.

If the fault is permanent, then of course the device has to act as a breaker and open up because it can only absorb the energy for a certain amount of time before it has to open. But because the solid-state fault current limiter is an electronic device, a technician in the central office can reset the breaker from his computer with the click of the mouse once the fault is repaired and everybody is back up. It's that quick. Or a technician in the field can reset it by logging on remotely to the network.

The FCL also allow a utility to keep their existing breakers deployed. This means the utility doesn't have to take its system down to upgrade existing breakers, which better serves customers and saves substantial costs. Furthermore, the fault current limiter can prevent an existing breaker from becoming overwhelmed, which extends the breaker's useful life. This is not a matter of kicking the old out in favor of the new, it's complementing the old with the new to make the grid better.