Renewable Energy

Tidal power experts discuss technological advancements, roadblocks to implementation

With Congress and the administration focusing on increasing renewable and alternative energy, does the answer to our energy needs lie in the waves of the sea? During today's OnPoint, Sean O'Neill, president of the Ocean Renewable Energy Coalition, and George Hagerman, senior research associate at the Virginia Tech Advanced Research Institute and a member of the Electric Power Research Institute's Ocean Energy Project Team, discuss tidal power and its future contributions to the United States' energy policy. Hagerman and O'Neill explain what tidal power is, how it works and how advanced the technology is. They also discuss roadblocks the tidal power industry has faced and talk about FERC's permitting process for tidal power sites.


Monica Trauzzi: Welcome to OnPoint. I'm Monica Trauzzi. Joining me today are Sean O'Neill, president of the Ocean Renewable Energy Coalition, and George Hagerman, senior research associate at the Virginia Tech Advanced Research Institute and a member of the Electric Power Research Institute's Ocean Energy Project. Gentlemen thanks for coming on the show.

George Hagerman: Thanks for having us. Appreciate it.

Monica Trauzzi: George, in simple terms, what is wave energy and how does it work?

George Hagerman: Wave energy is a way to harness sort of the up-and-down or back-and-forth motions of ocean waves that are driven by the winds. And so the challenge of that technology is because the waves are constantly every 5 to 10 to 15 seconds, they're either going up or down, or they're surging ahead or back. And the challenge is to take that very slow moving oscillatory motion and turn it into uni-directional rotation of a very high-speed generator. So there are lots of ways to do it, but that's the basic fundamental thing you've got, that's the fundamental challenge for any wave energy inventor or developer.

Monica Trauzzi: OK, and what kind of technology exists right now?

George Hagerman: Well, there are lots of them. And I don't think it's clear if there's any particular type that's better than another. That's still being sort of shaken out, but there's sort of three basic categories. There's what's called a terminator, where you present some sort of a large front. If the waves are coming at me from the camera and you present a large front end you either absorb the wave energy into some kind of a surging reservoir or an oscillating water column, are two variants of this terminator class. But any energy you don't absorb is reflected seaward, and that means that these devices tend to experience a lot of wave force and they create a low-energy shadow in their immediate lee. That's one category. Another one, which was in Popular Science this summer, is what's called an attenuator. This is a completely different kind of idea where you now have a very long device that's oriented into the waves and it pulls energy out of the waves as the waves go alongside. So let's a lot of energy go by it, but it pulls energy out of the waves as it travels along the length of the structure. And the Pelamis, which is the generic name for a sea snake, it's like a floating sea snake and it's harnessing energy as waves travel along it. The last category is what's called a point absorber and that would be like a heaving buoy, which is very small in relation to the wave length. So it doesn't present a big front or a long structure, but it usually heaves up and down in some form or fashion.

Monica Trauzzi: Sean, your group, OREC, is a national trade association for marine renewable energy. It was only created a few years ago. How much of a change in interest have you seen over those few years?

Sean O'Neill: Oh, in the last two years, to give you an example, we were started in April of 2005. Our membership than was four companies. We now have 35 companies. The four companies that started OREC were small technology development companies that George has worked with for years and years and years. The companies that now make up our membership include investor-owned utilities, very large technology developers like SAIC, large law firms. It's an industry that's really burgeoning overseas, and in the United States there's a lot of excitement.

Monica Trauzzi: And you're lobbying Capitol Hill for more tax benefits and support for marine renewable. How much are you asking for?

Sean O'Neill: It depends on exactly, we ask for what you can get. That's typically the way it works in Washington. But when you look at fostering diverse energy supplies we can leave no rock unturned. We really need help in terms of our entire energy policy and our energy supply. And until we get our energy supply right our Congress and our department of energy should be looking at everything.

Monica Trauzzi: But do lawmakers see this as a viable source of energy among all the other alternatives that they're being shown? I mean we have wind power, solar. Why this one?

Sean O'Neill: Well, what's interesting about it is you can't have a silver bullet to win in the energy marketplace. What you need is diverse supplies. So if you're looking at renewables you can't afford to zero out any single renewable. Traditional hydro, geothermal, unfortunately have been zeroed out, which doesn't make a whole lot of sense right now. We need to support all renewables and we need to do that right now. The idea of making electricity without any fuel is a wonderful concept. There's no fuel transportation. There's no environmental externalities. I love working with George because he can put it so much more eloquently. He uses all of these polysyllabic words, and quite frankly he's been working on diverse energy supplies, as I have been, for at least the last 20 years.

Monica Trauzzi: So let's discuss FERC's role in all of this. They're taking some time to evaluate the permitting process associated with tidal power. And as a result, the permitting process has slowed down. Why have they decided to take these steps and slow it down?

Sean O'Neill: Well, can I make a point though to the last question you asked?

Monica Trauzzi: Sure.

Sean O'Neill: I think it's important. What makes, as you said, you have a whole variety of different sources. One of the things though that is true of all renewables is they're regionally or seasonally more intense than in others. So the solar resource, for example on our coast, on the East Coast, peaks in the summer. Well, the offshore wind and wave resource peaks in the winter, so they're a natural complement. Each adds value to the other. If you start getting into, well, solar is the solution, then you have to pay the higher cost of dealing with backup power during the winter season. Likewise with waves or wind, it's the opposite. So I just wanted to make that point. That it's important, they're synergistic and that's part of the advantage of diversity. Sorry, didn't mean to ...

Monica Trauzzi: No, that's great. Onto FERC though.

Sean O'Neill: OK.

Monica Trauzzi: What's happening there? This permitting process is really being looked at.

George Hagerman: Well, FERC was established a long time ago under the Federal Power Act. They weren't really established to regulate new and emerging technologies. So they're learning how to cope with this brand new animal. For example, the Verdant Power project in the East River of New York City started its permitting process almost 5 years ago. It's cost them over two and a half-million dollars just to get the permits for a pilot project, a demonstration project in the East River. As a country we can't afford to drag our feet like that. When you look at countries like Portugal that are putting in 23.5 cents feed-in tariffs per kilowatt hour, the United States supports wind power for example with 1.9 cents. So you've got 1.9 cents versus 23.5 cent support for renewable energy. So there's a regulatory aspect that's slowing things down and there's also the political will, that the United States needs to step up if we're going to compete on a global marketplace of renewable energy.

Monica Trauzzi: What about all of these companies that were sort of trying to buy out all the space to eliminate competition?

George Hagerman: Yeah, can I, yeah, because I think that's kind of, the core of your question is why all of a sudden has there been this blossoming, particularly in tidal stream. If you look at the FERC web site you'll see that most of the projects are these tidal stream projects. And I think the reason for that is that, again, thanks to EPRI and the study they did with tidal energy, what we discovered with the tidal stream energy is because they're basically underwater turbines that they have already gained from all the learning and R&D that's been put into when the energy. Because they've got gearboxes and composite blades and all the things that, yaw bearings and that sort of stuff. So when we did our feasibility study we looked and found that in good tidal stream sites, such as exist in Maine and Alaska and San Francisco in the Golden Gate, that you could be competitive now with conventional. And that's almost unheard of, that a new technology, out of the gate, would be competitive in power markets. So I think that caused sort of a gold rush. Someone said, "Oh, wow, my goodness!" And so I think there was some people who said, "Well, we better take advantage of the FERC process," which was developed for mature technologies, "and kind of stake out our claim." And I think that's why actually FERC has said, look, we need to sort this out. We need to know who are real project developers? Who are people who are just banking sites? Who has mature technology, so they can take these national resources and bring them online commercially sooner. And so I think they're trying to sort of sort it out. I'm not so sure they're intentionally dragging their feet. It's just it's a new game for them and they're trying to get smart on how it works and who's who and that sort of thing.

Sean O'Neill: Well, also you've got different companies with different business plans. And it's prudent for some companies to go out and look at five or six sites at the same time because some of them aren't going to work out. So the idea of site banking might be something that is of concern, but even more concern is that when you get a FERC preliminary permit it ties up a site for three years. So you go in and you do your environmental studies, you do your other hydro kinetic studies and things like that. You've taken a public resource and for three years you've locked it up. And let's say you don't want to go with that site for commercial reasons, you leave with all of that data that you've got, which is proprietary, and you've really locked up that site for three years so nobody else has been able to look at it. And that's a concern.

Monica Trauzzi: What about the cost of the energy that's produced by tidal? Is it comparable to what we're currently seeing?

George Hagerman: Again, it depends on the resource. Just like with wind energy, the higher the average wind speed the lower the cost. And the same is true for tidal stream. Again, in the EPRI study we have found that sites that have tidal currents in the 2 to 2.5 meter per second, which is 4 to 5 knots, as sort of the average peak speeds, because tides, you know, they ebb and they flow. There's a peak and then there's a slack water and another peak. In that range we found the costs were in the range of four to five cents a kilowatt hour, depending on the financing structure and whether it was an investor owned utility or an independent power producer, etc., etc. And that's all in the reports on the EPRI Web site, which I would encourage your viewers to visit. The nice thing about the EPRI project is it's a totally transparent public benefit project. And so you can actually see how these costs of energy were generated and how they do vary from a slow site to a fast site. But there are sites in the US now definitely where it's cost competitive with new fossil generation.

Monica Trauzzi: What are some of those sites?

George Hagerman: Western Passage in Maine, which is down East in Washington County, the Golden Gate. There are some tremendous sites in southeast Alaska. In fact, one of these sites in southeast Alaska may be one of the biggest in North America. Again, EPRI just did that study. So anyway, you know, it's now coming out of the lab and out of the research community and being put into commercial practice. And there's bound to be some hiccups. And I think that's kind of what you're seeing, is sort of how do we dovetail what the researchers are now finding with the needs of commercial interests; and also the national need to preserve the public good, to provide secure energy, but at the same time protect the environment? That's a lot of different things to juggle in a sensitive area like the coastal zone.

Monica Trauzzi: Do we know about the environmental impacts of this yet? What about ocean habitat? Do we know enough about that?

George Hagerman: Yeah, I would say that our experience in both tidal waters and estuaries, as well as offshore in the wave environment, with other structures that we put offshore, like light towers and fiber-optic cables and wharves and navigation, aids to navigation. All of that has given us sort of the beginnings of an understanding of what would happen in the local environment. There is a need to actually put commercial scale devices maybe in small pilot arrays to really then monitor those. And indeed, that's what the East River Project, the Verdant Power, is all about. They're watching fish. They're looking to see how fish interact. And the nice thing about these tidal stream turbines is unlike a dam, where you've got a turbine that's in a closed tube called a penstock, where the fish, once they get sucked in, they're going to go through a high-speed turbine and be damaged or killed or severely injured, probably die. The tidal stream turbines, fish can avoid. They can sense it and swim around it. And the same is true with marine mammals, but nevertheless, those with environmental concerns would like to at least see that demonstrated. And that's why you've got, for example, these six turbines in the East River off New York. They'd actually say, OK, how do to the fish behave in a field of these? Not just a single device, but you've got like three or four of them in two rows. How do the fish navigate through that and do they appear stressed out?

Monica Trauzzi: We're almost out of time. I just wanted to get to this last point. Are there any NIMBY issues associated with this technology? I know with wind power for example, people didn't want windmills in the ocean in front of their properties. Does something like that exist with this technology?

George Hagerman: Actually, the NIMBY syndrome, if you would call it, oftentimes is a politically driven kind of phenomenon. When you look at a lot of the technologies they don't have the kind of view shed impacts that you would see with offshore wind that's close to the shore. But, of course, there's going to be stakeholders and you want to bring them into the process.

Sean O'Neill: Right, right. That's key I mean it's important to make sure that you involve the other users of the ocean. You know, we don't have people who live in the ocean, but we have people who visit it all the time for their work or their play. And so you need to make sure that they're involved as stakeholders in the site selection process to avoid a lot of the potential conflict. But in terms of view shed, which is the biggest, which is the one that certainly has come up say with the Cape Wind Project in Nantucket sound. Wave energy device is a very low freeboard, so they're close, they don't stick way up. Tidal stream devices are submerged, so they're really, for all intents and purposes, invisible. And then if you go over their horizon with offshore wind, again, you avoid the view shed. But you still have to involve the stakeholders, the community coastal stakeholders who use that water for recreation or work to make sure that we are not interfering with what they want to do.

George Hagerman: The bottom line, in terms of the projects, the few projects that have gone into the water, you've got the European Marine Energy Center, EMEC, which has had some environmental studies that have been done around projects there. You've got the project in Hawaii that Ocean Power Technologies had, which had a finding of no significant impact, but we called it a Fonzie. And you've have got the Verdant Project, which for two months in the water, in the East River of New York, they don't have any impacts on fish that they can detect right now. They've produced over 10 megawatts of electricity in just, I think, a little under two months. But you also have to look at the unintended benefits. If you put an array of turbines underwater out in the ocean and you say there's going to be no commercial fishing there, you may end up, just like with other structures out in the ocean, you may end up creating an area where fish breed. And they might breed even more prolifically than they do in nature, which some of the studies show.

Monica Trauzzi: All right. We're going to have to end it right there, we're out of time. Thanks for coming on the show. This is definitely a hot topic to watch.

Sean O'Neill: All right, thank you.

Monica Trauzzi: This is OnPoint. I'm Monica Trauzzi. Thanks for watching.

[End of Audio]



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