Ocean Energy -- Putting It All In Perspective

"As I continue to explore the use of ocean power technologies, I find it amazing that no matter where we go along the coasts of the continental U.S. and Hawaii, just about every area is suitable for at least one type of ocean energy technology."

- Dan White, RE Insider

[RE Insider] If I told you it was possible to generate enough power to sustain the United States forever without releasing greenhouse gases or noxious pollutants and without dependence on foreign nations-would you be interested? The U.S. Government doesn't appear to be.

Homeland Security means a great deal more than patrol ships, surveillance, intelligence, and devices for threat detection-all important. However, these things will not secure our nation without first establishing "energy security" which is directly related to the economy. Without a strong economy we would face a threat greater than any other we face today.

I love statistics-they serve as an effective "wake-up" call. The February 2005 issue of Fortune Small Business magazine was full of them in its focus called "Who needs Oil". Here's a few. "If the U.S. relied on its own oil it would run out in 51 months." "Appliances that are switched off but still plugged in account for 5% of U.S. energy consumption and cost consumers $3 billion annually." "The 20 states that lost 76% of the manufacturing jobs in the U.S. over the past 4 years also happen to have the technical capability to capture most jobs from the wind industry." "The sun sheds enough energy on Earth in one minute to meet its energy needs for an entire year."

Renewable energy may hold the key to both national security and economic stability as demand is surging in China, India and other developing countries, while, at the same time, production is falling in 33 of the world's 48 largest oil producing countries. U.S. oil production peaked in 1970 at 8 million barrels per day and fell to less than 3 million barrels per day in 2004.

Frank Gaffney, former National Security Advisor to President Reagan, put it best, "We find ourselves dependent on imports from people who, by and large, are hostile to us. It makes (energy independence) a national security imperative."

By the year 2025 as much as 68 percent of the U.S. Petroleum demand could depend on imported oil, according to the U.S. Department of Energy's Energy Information Administration (EIA).

The math is clear. We may always use some oil, gas, and coal, but we won't have enough, and no, nuclear energy is not a renewable source.

Ok, now some more leading questions. "What is the largest energy source on Earth?" -- that's right, the ocean. Most grade school kids know that the ocean absorbs heat from the sun, which, simply put, creates wind, which creates waves, in turn producing ocean currents. The sun and the moon work together to produce tides. The temperature difference between the warm surface waters and the cold deep waters of the ocean represent a significant potential energy source.

Here is another one. "Together, the seas and oceans cover an area nine times greater than the surface of the moon." This equates to about 369,315,000 square kilometers or about two-thirds of the earth's surface. How much energy does the ocean store, you ask? It is estimated that each day, the oceans absorb enough heat from the sun to equal the thermal energy contained in 250 billion barrels of oil. The world currently consumes more than 3 billion barrels of oil per day.

Can the ocean provide all the types of energy we require? Well let's see. First and foremost we need electricity. This can be provided by a number of approaches, e.g. offshore wind, wave power, current and tidal power, thermal energy conversion and even salinity gradients. Next we need fuel to power our transportation industry. Hydrogen and ethanol appear to be preferred fuels at the moment. Yes, we can get hydrogen and ethanol from some of the same machines that produce electricity in the ocean.

It appears that Europe is getting the message. North Sea oil fields are diminishing quickly, which has given rise to studies on how these countries will be able to provide themselves with energy in the future. In Europe, an estimated 150,000 square kilometers of ocean would provide an area for offshore wind farms that would provide enough power to satisfy all of Europe's electricity demands. It is estimated that 0.1% of the energy in ocean waves could be capable of supplying the entire world's energy requirements five fold. The UK and Australia already lead the world in Ocean Energy technology implemented utilizing wave and current devices.

There are many ways to look at our growing need for electricity. Take just the United States for example. According to the 2004 World Energy Report from the International Energy Agency (IEA), at an annual use of 3,659,990,000 MWhrs in 2002 the U.S. wins hands down for total energy needs of all the developed countries.

Now, just for fun, how many wind, wave, current plants would it take to provide 10 percent of the United States' power requirements? First we must make an assumption on how much electricity the plant will produce. To do this I will take the Cape Wind offshore wind farm and extrapolate a number. This wind farm is a 420 MW (peak installed capacity) project that will produce about 1.5 million MWhrs per year. If we use this number, which takes into account the wind patterns over a year, we should be conservative in our calculations.

The top 12 users of electricity represent more than 70% of the total worldwide usage. Total MWhrs for those nations in 2002 was roughly 10,000,640,000 MWhrs, according to the IEA. The world total for the same year was 14,283,530,000 MWhrs.

For less than 10,000 worldwide ocean energy power plants of only 500 MW, you could have a world powered by clean renewable energy and reverse global warming. I'm not selfish. We should consider all renewables in this equation, at least the ones that do not use fossil fuels in their process (e.g. the predominant hydrogen generation techniques use fossil fuel). If one decided that ocean energy would provide 10 percent of the world's electricity, then that would equate to 952 ocean energy farms. The U.S., alone would require only 244 power plants -- now it starts to make a great deal of sense! The U.S. has some 10,759 miles of coastline, that would equate to one power plant/farm per 44 linear miles along the coastline.

The Cape Wind installation is 130 wind turbines, which will produce 420 MW of electricity or 3.2 MW each. The wind farm will occupy 24 sq. miles producing 62,500 MWhrs per sq. mile.

Back to the 244 ocean energy farms off the U.S. coastline. We would only require 5,856 sq. miles (an area 77 miles by 77 miles) to achieve our 10% goal. This does not take into consideration deepwater installations such as wave, Ocean Thermal Energy Conversion (OTEC) and current, and larger installations, which would increase the spacing of energy sources.

The U.S. was a tough one because of the amount of electricity we use. However, with fossil fuel availability diminishing, ocean energy will be required to supplement our growing need for energy.

Now, let's look at an island nation like Jamaica. Jamaica used 5,850,000 MWhrs of electricity in 2002. That would have required 4 of our 500 MW ocean energy plants to power the entire island. It is feasible that just two OTEC plants could provide 100% of this requirement and provide millions of gallons of fresh water daily as a byproduct-what a bonus for islands!

The facts about the use of energy from the ocean are indisputable and with the large concentration of populations along coastal areas, ocean energy can be found nearby.

Energy without any harmful emissions or global warming effects, and in some cases such as OTEC, has the added benefit of freshwater as a byproduct. A 10 MW OTEC plant could produce about 3 million gallons of freshwater per day -- a real bonus for islands or developing countries.

The technology for putting equipment in the ocean was developed years ago and has been demonstrated repeatedly in oilfield applications. If we (the world's engineers, designers and manufacturers) can build an offshore oil rig such as BP's 75,000-ton, semi-submersible offshore production, drilling and quarters platform-Thunder Horse-and bring it across the ocean from Korea on a giant vessel, then moor it with a 16-point semi-taut chain-wire-chain system in 6,040 feet of water-I think we can safely say we can build and install offshore ocean energy plants of any kind, size, shape or water depth.

As I continue to explore the use of ocean power technologies, I find it amazing that no matter where we go along the coasts of the continental U.S. and Hawaii, just about every area is suitable for at least one type of ocean energy technology. (pull quote)

There is no one choice-wind, wave, current, tide, OTEC, etc. Each technology will need to be used to meet the U.S. energy needs. There is no one location. All areas will have to be exploited.

Now my least favorite... "Is renewable ocean energy a national priority?" Sadly no. But it once was!

From about 1977 to 1983, there was a movement towards harvesting Ocean Energy that is unmatched today. In 1980 and 1981 the U.S. Department of Energy's appropriation for Ocean Energy Systems alone was over $30 million, but the money disappeared over time as budget cuts forced its eventual demise, and the demise of the agencies responsible for overseeing the technology.

Ocean Energy's time is here. The government, and yes, even the oil & gas companies must take the lead in moving the technologies forward, not favoring any one renewable energy type over another. Remember the train companies - if they had realized they were in the transportation business they would probably be flying jets. Trick question-What business are the oil & gas companies in? Maybe the numbers I used in this article are arguable, and I can imagine that some will want to argue. But that's not the point. No one has yet to show me that Ocean Energy is unfeasible. Energy independence is just around the corner...or should I say "just offshore".

About the Author

Dan White is the founder of Technology Systems Corporation and the publisher and editor of Ocean News & Technology magazine. In addition, he is the organizer for EnergyOcean 2005. The conference will be held in Washington D.C. April 26-28, 2005, http://www.energyocean.com.
Mr. White holds a B.S. in Ocean Engineering from Florida Atlantic University. For over 20 years prior to starting the publishing company in 1993, Mr. White worked for several companies in the defense, oil & gas and ocean science industries. Dan can be reached at dwhitetsc@mac.com

The information and views expressed in this article are those of the author and not necessarily those of RenewableEnergyAccess.com or the companies that advertise on its Web site and other publications.

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