Developing Renewable Energy

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The effects of the recent global economic downturn have been wide-ranging and far-reaching. While nations around the world have increased their commitments to develop renewable energy, the green technology sector has not been immune to the vast fiscal crisis. Case in point: the Aguçadoura Wave Park in Portugal - which sounds like a family-friendly water park but was actually the world's first commercial wave-power farm - was suspended indefinitely because the project's majority owner fell into bankruptcy.

Wave power technology is still in its infancy. Various companies are putting forward myriad concept designs, most of which remain in the testing phase. The basic idea is to harness power through the motion of waves at or near the ocean's surface; as the waves oscillate, the wave power device activates hydraulic rams that generate power. That power is carried to the grid through undersea cables.

The technologies closest to viability are so different that it's easy to infer either limitless potential or disappointing impracticality. Intense design and maintenance will be required to ensure that any wave installation will stand up to the harsh punishment the ocean routinely dishes out. Beneath this seemingly hostile volatility, however, lies a certain calm steadiness. The power output from wave devices is more predictable since it does not rely on wind patterns - the ocean is always moving and waves are never used up. Further, energy generated in this manner results in zero carbon added to the atmosphere.

The Wave Park in Portugal mentioned above utilized a design from minority owner Peramis Wave Power and had been active for about a year prior to the recent suspension. Power was produced from three 400-foot snake-like tubes divided into four different segments; as the waves rose and fell, the joints between each segment compressed and released. These generators represented the first of three planned phases and produced power for 1,000 homes. The three devices are currently on-shore for repairs and are not projected to be re-deployed until Peramis can find a new majority partner.

A New Jersey company named Ocean Power Technology created a completely different design called Powerbuoy, several of which were deployed off the coast of northern Spain last year. In this iteration, a buoy sits on top of the ocean as a sort of rig connected to a piston that extends several feet below the surface of the ocean. As the waves move, the buoy shifts up and down around the piston and, again, energy generated is transferred via cable to land. The installations must be placed at least three miles from shore and each individual unit can power 150 homes. Because they are so small, however, many buoys can be placed close together to increase the power generated per unit of area. A set of Powerbuoys are set to go online this year off the coast of Oregon.

Texas-based Swell Fuels uses a different application of a similar idea in its generators, which are undergoing live tests in Indonesia, South Korea and El Salvador. Whereas the Powerbuoy relies on a floating buoy and a heavier piston, the Swell Fuels Trojan uses a heavier base as a counterweight to a lighter lever that moves with the water. The lever pumps up and down, which moves the hydraulics inside the base station. The Swell Fuels design is even more interesting given recent experiments in the Maldives on coral reef growth. By passing low levels of electrical current through a metal frame in the water, scientists were able stimulate the growth of coral reef. Creators of this wave generator speculate that the electrical charge carried in the frame could possibly offer similar benefits to existing reefs.

As these early models show, wave power shows a lot of potential, but the technology is still extremely young. It’s too early to tell which of these designs will prove superior. As with any functional design undergoing testing, a handful of ideas sink due to shortages of funding, imagination or feasibility. Additionally, it remains to be seen how much power can realistically be drawn in this manner without affecting shipping lanes or marine wildlife patterns. Still, any research into clean technology is a step forward--and advances in wave energy can only be a good thing on a planet that is 70% water.