Tidal Power: Tapping Energy from the Ocean Could ocean waves be the next renewable energy source? A new bill in Congress proposes spending millions of dollars a year to harvest marine energy. How much renewable power lies in the sea surf? Guests discuss what it will take to bring the technology into use.
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Tidal Power: Tapping Energy from the Ocean

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Tidal Power: Tapping Energy from the Ocean

Tidal Power: Tapping Energy from the Ocean

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IRA FLATOW, host:

You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.

Up next, harnessing the motion in the ocean. And I know if you've ever been swimming in the ocean - you've been out there this summer, you surf the waves and you've been knocked by the waves of the ocean - you know how forceful that water is, right? There's a lot of power. Water carries a lot of energy with it. Have you found you saying to yourself, well, why not find a way to tap all of this wave energy and turn it into electricity? Why, we have an inexhaustible supply, the ocean doesn't stop, the waves never cease coming to the shore, as the song says?

Well, the idea is not a new one, but what is new is that serious people are taking the idea seriously. Congress is even currently considering an energy bill that would provide $250 million for harvesting energy from the oceans, from the seas. This would be the nation's largest investment in wave energy ever. But with or without this bill, wave farms have already begun cropping up offshore around the globe.

George Taylor has a Ph.D. in electrical engineering and is founder and CEO of Ocean Power Technologies, a New Jersey-based wave power company. OPT is currently working on wave farm projects off the coasts of Spain, Hawaii and Oregon. Welcome to SCIENCE FRIDAY, Dr. Taylor.

Dr. GEORGE TAYLOR (Founder and CEO, Ocean Power Technologies, Inc.): Thank you.

FLATOW: You're welcome.

Our second guest is Sean O'Neill. Mr. O'Neill is founder and president of Ocean Renewable Energy Coalition in Washington. It's a trade-based organization that works to promote marine renewable power. Welcome to you.

Mr. SEAN O'NEILL (Founder; President, Ocean Renewable Energy Coalition): Well, thank you, Ira. And thank you for focusing on progress in wave and marine renewable energy.

FLATOW: Well, I know there's a lot - there's actually a conference going on in Oregon that's actually the second one of its kind. And it's kind of stuck under the radar. People don't think about wave energy very much, Sean, do they?

Mr. O'NEILL: Well, actually over the last two years, people are getting excited about it. And there's conferences being held throughout the world. The conference here at Oregon State University - I'm actually at the NPR affiliate on OSU's campus - and there are some tremendous speakers that are speaking right now on wave energy as well as tidal and other forms of energy that come from the ocean.

FLATOW: Give me an idea of the potential of the ocean and what different technologies are you guys discussing out there?

Mr. O'NEILL: Well, off the coast of the United States, it's been estimated by the Electric Power Research Institute that there's 252 million megawatt hours a year. That's equal to about six and a half percent of the total capacity in the United States. Internationally, there's 81 different technologies that are being looked at. In the United States, we're focusing on 14. And in the United Kingdom, they are looking at 34. But of the 14 in the United States, you'll look at pioneers like Dr. Taylor with Ocean Power Technologies and you can see that they've got a robust commercial endeavor going. And his representative out here in Oregon did a great job this morning, speaking at the conference.

FLATOW: Mm-hmm. And what other kinds of technologies are there? Do they harness the breaking waves? Do they harness the rise and fall of tides? Do they - well, you know, the swells, or all of those things?

Mr. O'NEILL: All of the above. But I'll let Dr. Taylor talk a little bit more about how wave energy works.

FLATOW: All right. George, you're on. Tell us about your project. And you have actually some demonstration projects going on, right?

Dr. TAYLOR: Yes. We've been testing out systems in the ocean for 10 years. We've got over three years of in-ocean experience, and have been able to demonstrate that our system will produce power over a wide range of waves and is able to survive hurricane wave forces. We have built our system around a well-known marine device called a buoy, and of course, there are many buoys in the water that are used for navigation purposes.

Our buoy is a modification of that type of buoy. It's one that moves up and down, bobs up and down, on the wave. And that motion, that mechanical motion of the buoy moving is then converted using some very sophisticated electrical systems and computer systems to control it. It's converted into high-grade electricity, which can then be connected on to an underwater cable and fed ashore and directly connected into the electrical grid.

FLATOW: Mm-hmm. So how many - how much power can these - or one of these buoys produce?

Dr. TAYLOR: Well, our workhorse, as we call it - as we are building wave power stations in various spots of the world that you mentioned - is 150 kilowatts. And, therefore, to build a 10-megawatt wave power station would take approximately 60 of these buoys arranged in a rectangular array, very closely packed array, typically located two to three miles off shore. Most of the structure is below the surface of the water. Therefore, is not visible from the shore so there's no visual pollution. There's no problem with sea life. Fish actually see it as an artificial reef. It's a positive aspect for fish. Larger sea animals are used to buoys in the water and can navigate around them.

We've had an environmental permit done by the U.S. Navy for a wave power station that we're building in Hawaii. And that permit would have found a finding of no significant impact, which is the highest level of permitting that you can obtain. So it looks as if wave power has all the advantages that one needs in a renewable energy source.

First of all, wave energy is very consistent. As you noted, originally, it's very predictable. We can tell three days out from satellite photography what the waves are going to be by the time they reach the wave power station. We're - typically at the good wave power sites - able to produce power 90 percent of the time. We are able to get a load factor of as high as 45 percent. That's considerably higher than solar, which is around 10 percent, and wind, which can be as high as 35 percent. And that load factor comes down to determining what is the economics. And we believe that within three to five years out, we will be able - as we scale up volume production, we will be able to produce power at 5 cents a kilowatt hour, which is the number that fossil fuel energy is currently at. So we would have the ability to produce considerable amount of energy at prices competitive with fossil fuel with no environmental issues.

FLATOW: When you say load power - load factor, I'm assuming that's the energy efficiency.

Dr. TAYLOR: Yes. That's a way to look at it.

FLATOW: How high do you think you can get that efficiency level?

Dr. TAYLOR: Well, we've seen wave sites where we can get over 50 percent. In other words, the rated power of the wave power station on the average over all the hours in the year, we'll be getting 50 percent of that out in the way of energy.

FLATOW: Mm-hmm. I also noticed - perhaps it was on your site or some other people were talking about the possibility. If you're making buoys out there, could you not make moorings for boats that would actually be able to plug in. You have little power generators for the boat that would…

Dr. TAYLOR: Well, that's part of the…

FLATOW: …bob up and down in the water.

Dr. TAYLOR: To recharge those?

FLATOW: Yeah.

Dr. TAYLOR: Absolutely. And we - there are also many other applications beyond the utility application and we have contracts with the U.S. Navy. For example, oceanographic observatories, there's a lot of interest throughout the world in being able to measure all types of things in the ocean, including, of course, tsunami warnings and that type of thing. But a whole range of scientific data people need to collect.

And one of the limiting factors on doing this is the - having power out there in the ocean. If you use batteries, then you've got to go out and replace the batteries regularly. Solar and wind are not good solutions out there in the ocean. And what we have developed, we've already found as a very willing market, a very interested market in this, what we call, autonomous power buoys which can be anywhere out in the open ocean.

FLATOW: Mm-hmm. The energy bill in Congress that would provide $250 million, would that help you or hinder you or create competition for you?

Dr. TAYLOR: No. That is very good. We welcome competition. We are in the fortunate position of having done a public listing of our stock three and a half years ago on the London Stock Market. And then this last April, we did an IPO on NASDAQ so we were able to put together the capital that we need to fully commercialize our system. So we obviously are very pleased with the interest that the federal government is taking in wave power because during this interim period over the next three to five years, as we scale up and learn to fully commercialize our system, the extra support, which wind and solar have previously received, will be a great benefit to wave energy and accelerate the full commercialization of wave energy systems.

FLATOW: Let me go to the phones. Ken(ph) in Stockton, California. Hi. Welcome to SCIENCE FRIDAY.

KEN (Caller): Hi. Nice to be here. One of my questions you already answered, but the other question that I have is when you're generating wave power, does the power come in surges or is it leveled off by the mechanics of the - what's underwater?

Dr. TAYLOR: It comes in pulses. However, built into our electrical system, we have what are called super capacitors that are inside the buoy. And these are electrical devices that smooth the power out.

KEN: Thank you.

FLATOW: Thanks for calling. It's sort of like a filter system of an AC current that filters it into DC. Does it come in as DC or AC?

Dr. TAYLOR: It comes in as the - the basic energy comes in as AC where the amplitude of the AC is proportional to the height of each individual wave. And the frequency varies because the frequency or the time between waves varies.

FLATOW: Right.

Dr. TAYLOR: So you get this very strange AC, and then we convert that into DC and then we - then reconvert it into a 60 hertz AC, which can then be fed directly into the electrical grid.

FLATOW: Right. You know I can't remember if it was Michael Faraday or somebody who discovered that if you take a magnet and you run it alongside a wire, you get electrical current in the wire.

Dr. TAYLOR: Yes, that's correct.

FLATOW: Is that basically how your systems work?

Dr. TAYLOR: Well this the way we generate the electricity. We - the movement that Faraday did, you know, by moving the wire in the magnetic field, that is what the waves do for us. They move part of our system through the magnetic field and thereby create the electrical current.

FLATOW: 1-800-989-8255. Sean O'Neill, you don't see wave powers taking over all of energy in this country, do you? Or is it sort of just a part of a larger energy picture?

Mr. O'NEILL: Well, when you're talking about electricity supply, diversity of supply is key to reliability. And within the whole marine renewable sector, you've got wave energy. You've got tidal energy. We have the first tidal project off of Roosevelt Island in New York City. There's also other products produced other than electricity. You can desalinate water. You can produce hydrogen. So there's a lot going on there.

FLATOW: Mm-hmm. 1-800-989-8255. Let's go to David(ph) in New York, New York. Hi, David.

DAVID (Caller): Hi. Thanks for having me in the discussion. I just wanted to deposit a word from the architecture world. Actually, there was a student that I was lucky to work with, actually, on his project at Princeton University - Yusuke Obuchi.

He produced a project called the Wave Garden, where essentially he created a sort of an offshore, kind of, qualifiable park landscape where it was gigantic panel-like tiles of piezoelectric material. From what I understand, it's used in, for instance, army boots to sort of recharge batteries as it moves, or an artificial muscle technology.

And, essentially, the movement of the surface as it rested on the water would create energy for the community on shore. And as a reward, if the community on shore then had conserved or not overused or spent energy outside that source, then the entire surface would lift above the water and become a shapeable landscape for them to have recreation and whatever other activities.

It's really a beautiful project. I'm so sorry we can't see it over the radio but it eventually got into - was accepted into the Cooper-Hewitt National Design Museum Design Triennial, I believe in 2003, and was awarded best in show by former New York Times art teacher critic Herbert Muschamp. And I'll take my comment off the air. Thank you.

FLATOW: Congratulations. Let me remind everybody that this is TALK OF THE NATION: SCIENCE FRIDAY from NPR News. Talking with George Taylor and Sean O'Neill.

Any comment on that? Has wave energy now gotten the attention you think it deserves?

Dr. TAYLOR: Well, we think it's happening very quickly. It's very apparent in Europe. The U.K. has taken a very positive attitude, and has put in place incentives to encourage wave energy. We have two projects that are just beginning, one up in the north of Scotland, in Orkney Islands, and another one shortly down in Cornwall, where both programs are very strongly supported by the U.K. and the Scottish government.

FLATOW: Any demonstrations here on this, in the States?

Dr. TAYLOR: We have had the system off the coast of New Jersey for over a year. We recently took it out of the water because we just wanted to see what wear and tear had occurred, and it's about to go back into the water. We were very pleased to find that there was minimal wear and tear. Obviously, that's an important ingredient in building power stations. Our systems are designed to last 30 years. They require regular maintenance, but this is all baked into the economics of the system.

FLATOW: Sean, I've got about a minute or so left. If it's so great, why don't we see everybody using it?

Mr. O'NEILL: Well, we are seeing a lot of other countries using it. And in the United States, with the passage of the Energy Policy Act Of 2005, the United States started to acknowledge the whole host of marine renewable technologies. With energy bills that are going through Congress right now, we're seeing a much greater interest in funding research and development and providing tax incentives. We're still a long way in terms of catching up with countries like Portugal, Denmark, the United Kingdom, Scotland, Ireland, even Japan and China.

Dr. TAYLOR: On that, too, Sean, I'd like to add in that the - it's great to see the federal government moving, and also several of the state governments in the U.S. are very proactive. Oregon is one of these. The governor of Oregon has stated that he wants Oregon to be the wave power capital of the United States. And there's legislation in place in Oregon, which is very advantageous for us. We've recently applied for three different sites in Oregon, which would be a total of 250 megawatts of wave power station.

FLATOW: So once again it's the Europeans and other folks leading us into another technology.

Mr. O'NEILL: Well, we're very quickly catching up. And I would say within the next three to five years, and I'll be as optimistic as Dr. Taylor has been, we will catch up. But it's going to happen because of the political will and the support that other renewable energy technologies have received in the past. And now they're - we're starting to get that attention.

FLATOW: That's a nice piece of change in that energy bill - $250 million, if it…

Dr. TAYLOR: Well, that's the kind of funding that really is needed to produce significant size power stations, and to do it quickly. I mean, I think the world needs to move quickly and produce non-polluting energy. So I think this is - these are the right numbers.

FLATOW: All right. We're going to take a short break come back and talk lots more with George Taylor, CEO of Ocean Power Technologies; Sean O'Neill, founder and president of Ocean Renewable Energy Coalition. Take some of your calls on the other side of the break, so stay with us. We'll be right back.

I'm Ira Flatow. This is TALK OF THE NATION: SCIENCE FRIDAY from NPR News.

(Soundbite of music)

FLATOW: You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.

For the next few minutes, we're going to continue our discussion about wave power with George Taylor, who is CEO of Ocean Power Technologies; and Sean O'Neill, founder and president of Ocean Renewal Energy - Renewable Energy Coalition. Our number 1-800-989-8255.

Let's go to Joel(ph) in Brewster, Mass. Hi, Joel.

JOEL (Caller): Hi. If you people are going to extract a significant amount of energy from this wave action, you're going to significantly reduce the wave action, which means that you're going to significantly change the ambient environment of the water and the coast and the bottom, and what have you. Same as with tidal action, if you're going to - which I've heard talk of even in the Bay of Fundy damming an entire situation to create a head of water at low tide, you're going to change huge amounts of tidal currents. They're talking about completely changing the resonance of the tides in the Gulf of Maine, in Cape Cod Bay, and what have you. I'm one - and there's also a price of wind…

FLATOW: Let me get…

JOEL: I'm curious is there…

FLATOW: Hang on.

JOEL: …anybody who is looking into what's going to happen to the ambient environment?

FLATOW: George Taylor, are you…

JOEL: (Unintelligible).

FLATOW: George, are you concerned about this?

Dr. TAYLOR: Yes, we've looked at this very carefully. We occupy an extremely small portion of the ocean. For example, a 10-megawatt wave power station would only occupy 17 acres. And as I said, it is typically two to three miles offshore, very compact, the buoys are very close to each other. If the efficiency of the conversion is 50 percent, then the waves that are going through that rather small dimension would be reduced, the energy in them would be reduced by 50 percent. However, that is a minimal amount given the long length of the coastline.

So it's - unless you went extremely overboard and, you know, sought to take every megawatt you could out of the ocean - we're a long, long way away from that. It's almost like the wind, too. I mean, if one put up a lot of wind turbines, would you stop the wind? In theory, yes, you would. But to get to that level is way beyond anybody's expectation. The amount of energy, as was pointed out by Sean, renewable energy is going to be a mix of wind, wave, solar, biomass. Each of them is going to play a part. But none of - wave, for example, is not going to affect the in any significant way the coastline or the environment.

FLATOW: Let me go to Nick(ph) in Portland. Hi, Nick.

NICK (Caller): Yes. Good morning. I wanted to bring into the conversation the subject of tidal energy. There's a technology marketed by an outfit called Blue Energy in Vancouver, B.C. that utilizes a thing they called a Davis Hydro that will harness very low-head and no-head velocities of tidal currents. And as such, then no dams or weirs or barrages are necessary. Can - has - I'd sure like to see this technology vetted by those brighter than I.

Mr. O'NEILL: Well, that's an excellent comment. In fact, there are several companies involved in tidal energy that are producing turbines that do not require any impoundment. And not to dismiss the calls or the concerns of the previous caller, part of the funding in the energy bills that are wafting through Congress this year will go towards environmental studies and make certain that all stakeholders' concerns are properly addressed.

FLATOW: All right. Thanks for your call.

NICK: Yeah.

FLATOW: 1-800-989-8255. We've run out of time. I'd like to thank my guests. George Taylor is a founder and CEO of Ocean Power Technologies and is currently working on a wave farm project off the coast of Spain, Hawaii and Oregon. Sean O'Neill is founder and president of Ocean Renewable Energy Coalition based in Washington, D.C. Thank you gentlemen. Good luck to you. Thanks for taking time to be with us.

Dr. TAYLOR: Thank you very much, Ira.

Mr. O'NEILL: Yes, thank you, Ira.

FLATOW: You're welcome.

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