5 Ways to get energy from the ocean

1 of 6

Capturing the Power of Waves

As debates continue to rage globally over how exactly a booming human population will continue to fuel itself—coal, oil, natural gas?—new options continue to gain ground.

Take wave power, for example. While the sun has a habit of disappearing overnight and winds can be fickle, the ocean—which covers nearly two-thirds of the planet—is constantly on the move. In fact, the U.S. Department of Energy estimates ocean wave and tidal currents have the potential to account for 15 percent of the nation’s electricity by 2030.

While attempts to harness the ocean’s tides and waves have been going on for years, the technology may have recently turned a corner toward becoming reality. Scientists from around the globe are currently tinkering with buoys and trying to figure out the most efficient and cost-effective ways to harness our oceans’ power. And one of these projects could take the first steps we need to achieve consistent renewable energy. Click through to learn more about them.

(Photo: Rachel_thecat/Creative Commons via Flickr)

Does It Float?

In a lab at Texas A&M University, a team of former U.S. Air Force Academy aerospace engineers have been experimenting with a new generation of wave power tools in a tank half the size of a football field. Typically used for testing offshore oil and gas platforms, the tank has recently been used to test a prototype device that uses components similar to airplane wings to generate power.

Incoming waves rotate a pair of wings around a central axis and the movement activates generators, which transform the mechanical energy into electricity. The team believes that the mechanism, floating just below the ocean’s surface, can successfully capture 95 percent of a wave’s energy. The prototype, about one-tenth the size of a full-scale device, produced 370 watts during testing; a full-scale version should be able to power 3,000 to 4,000 homes. Of course, there are differences between testing in a tank and the ocean, where storms, marine life, and an unpredictable environment can mess with equipment.

“The engineering issues are huge,” team leader Stefan Siegel admitted to the Houston Chronicle. “It’s much more difficult than getting an airplane in the air.”

(Photo: Oceanflow Energy/Creative Commons via Flickr)

On the Sea Floor

In Australia, the national science agency said last week it thought that all ocean renewable energy sources (ORE—wind, tides, and currents) could provide enough energy to power the city the size of Melbourne by 2050. While tidal and ocean current power are both still very experimental, the agency suggested that wave power remains “potentially the single greatest ORE source” and could eventually provide 10 percent of Australia’s electricity needs. Anchoring and protecting devices from an occasionally wild ocean are still big questions, but in terms of investment, the science agency is convinced spending on wave power today, particularly near the windiest parts of the coast, will ultimately be more valuable than putting more money into carbon-based fuels or nuclear.

(Photo: Courtesy of BioPower Systems)

Float With the Waves

The U.S. Navy has decided that energy security should be a priority and is turning to its own backyard, so to speak, testing wave power technologies off the coast of Kaneohe Bay in Hawaii. Its first test is with buoys designed to trap energy from the motion of waves, which will then convert it into a viable energy source. Electricity generated is being added to a grid system in the region, which is already fed by solar power generated at a base in Pearl Harbor. The Navy’s rationale for such testing? In addition to providing clean energy, these alternative sources will make the U.S. less reliant on foreign power sources, which so often comes with saber rattling and military incursions.

(Photo courtesy of CSICO)

Catching the Waves

Across the pond, a pair of Finnish inventors are testing wave power converters in the Atlantic Ocean. The so-called “WaveRoller,” dreamed up by diver Rauno Koivusaari, is undergoing tests off the coast of Portugal. Then there’s “The Penguin,” a converter being worked on off the coast of Scotland and named by its inventor, Heikki Paakkinen, for the way it sways with the waves and spins at an interior generator.

Paakkinen is managing director of a company (Wello) that specializes in wave energy. “We can prove these things with calculations and tests,” he tells YLE News, “but in the end people will only believe when they see something for real. So we make a full-scale version.” The Finns believe that wave energy will ultimately grow into a multibillion dollar, homegrown industry.

(Photo: Courtesy of AW Energy)

Capitalizing on Coastal Currents

In mid-July, Massachusetts government officials, marine biologists, and scientists gathered near the Muskegat Channel to watch the launch of a barge carrying the latest in wave-generating machinery. The hope is that the channel’s powerful tidal currents, which can exceed six mph, will test this new-era tidal current generator. Funded by Massachusetts Clean Energy Center, the project will hopefully reduce local dependence on fossil fuels of all kinds.

(Photo: Courtesy of Wavegen)

Do you think the ocean can solve our energy needs? Tell us in comments.

Related Stories on TakePart:

• Underwater Heatwave: 5 Frightening Results of a Boiling Ocean

• The Climate Change Disaster You Didn't Know Existed

• Raw Sewage: The Next Environmental Catastrophe?

A six-time grantee of the National Geographic Expeditions Council, Jon Bowermaster has spent the past two decades circling the world’s ocean, studying both its health and the lives of the people who depend on it. He is the author of 11 books (his most recent, OCEANS, Threats to Our Seas and What You Can Do to Turn the Tide, was published by Participant Media) and producer of a dozen documentary films. His blog—Notes From Sea Level—reports daily on issues impacting the ocean and us. Follow Jon on Facebook. @jonbowermaster | Email Jon | TakePart.com