Ocean energy technology, a largely untapped resource until recently, has emerged as a practical and potentially more reliable form of natural renewable energy than wind or solar. With Europe and North America taking the lead in research, and Australia launching hefty projects of its own, the process of harnessing wave energy into generating electricity is gaining traction among investors and coastal companies in the process of constructing wave farms. Ocean waves contain massive amounts of potential energy that are highly consistent and predictable. With cheaper operational costs and more widespread implementation, wave energy mechanisms could power electricity for many coastal towns and provide a major source of energy generation in the race to convert to sustainable power options.
Although wave technology has been traced back for decades, intense research has only sparked recently out of practicality and benefits that could eventually challenge solar and wind energy. The first wave energy demonstration devices were deployed in the 1970s, but progress stagnated until recent renewed interest. Currently, there are over 200 different wave energy converters (WEC) in various stages of development, from the United Kingdom in particular and recently Australia. The types of WEC can be grouped into three classes: point absorbers, attenuators and terminators (1). Point absorbers are small devices that extract wave energy from all directions underwater. Attenuators are jointed and longer than the wave, thereby extracting wave energy through movement of the different parts. Overtoppers are large in size and face directly into the wave for greatest impact. Popular Mechanics recently featured some of the most impressive models of wave technology to date, each of which utilized different mechanical functions to acquire energy. The Pelamis Wave Energy Convertor by Pelamis Wave Power, for example, is dubbed “sea snake” because it is comprised of four big cylinders strung together by hydraulic joints that bounce with the waves (2). This movement pumps oil through hydraulic motors that drive generators to produce electricity. Another, the GreenWave by Oceanlinx, consists of an underwater tunnel that floods with incoming waves and compresses air inside the cabins, making it rush out the air vent and harnessing energy. The United States Air Force Academy developed a device as well, called The Terminator. This one, using ideas from airplane design, utilizes wing-shaped turbine blades that force water to flow faster over one side than the other, creating different pressures on each surface and lifting towards the low-pressure side. The engineer and owner of Terminator asserted that this lift technology rather than drag, or brute force of the water, allows for the device to capture 99% of the wave’s energy (2).
According to the energy division of the European Commission for Research and Innovation, an estimated 0.1% of the energy in ocean waves could supply the entire world’s energy requirements five times over (3). This conversion process can take several forms, including tidal and marine energy, wave energy, difference of temperature and salinity energy, and is comparable to the energy used in hydroelectric power plants. Although the European Commission has been funding research in ocean energy technology since the late 1980s with its 2nd Framework Programme, funds increased substantially since 2002. Projects that have totaled over 55 million euros in government funding are continuing to work towards developing more cost-efficient floating devices, designing less intrusive off-shore conversion platforms, and strategizing for ocean energy and coordinating activities (3). The European Union, pressed to meet ambitious renewable energy standards by 2020, has been promoting Ocean Thermal Energy Conversion, or OTEC. This utilizes the difference of temperature between cold, deep seawaters and warm, shallow ones to create a thermodynamic cycle that produces electricity (3). Other research funded by the EU includes using the difference in salinity between seawater and freshwater in coastal regions to create a pressure difference engineers can then exploit for energy extraction.
Because wave technology energy is still relatively new outside of theory, new companies can still enter the market by introducing new technologies that reduce cost, space, and hassle. Regionally, the market for wave energy has been segmented into North America, Europe, Asia Pacific, and ‘Rest of the World’ (4). Current funding for ocean energy includes a major backing by the European Commission for Research and Innovation that aims to improve non-technical barriers, such as politics and garnering community support. Two of the commission’s majorly funded projects currently are CORES and EquiMar. CORES, which stands for Components for Ocean Renewable Energy Systems, concentrates on power-take-off, control, moorings, risers, data acquisition and instrumentation based on floating systems (5). EquiMar, on the other hand, deals with the ambitious goal of standardizing the evaluation of different marine energy converters, as some are based on tidal energy and others use actual wave energy (5).
Aside from public funding, European companies focused on wave energy have taken major strides in recent years. Leading company Scotrenewables, based out of the Orkney Islands in Scotland, is using a unique floating tidal technology designed to minimize installation and operational costs. Founded in 2002, Scotrenewables has developed models that utilize two propellers that fold up when being towed for manufacturing and transferability benefits. Its first fully functioning prototype, the SR250, was so successful that the company was able to showcase the larger SR2000 by June of this year, with further technological improvements and full implementation to come by 2017 (6). Deemed by the European Marine Energy Centre as the world’s biggest and most powerful tidal turbine, the SR2000 towers at 550 tons and 64 meters. Seatricity Limited, a wave energy business based out of Falmouth in the United Kingdom, deployed a full scale prototype named Oceanus 2, a wave energy convertor buoy that has been in progress since mid-May. The promise with this technology lies in its mechanical simplicity, as it links buoys together to maximize the latent power of the oceans’ waves (7). Beyond Seatricity’s simplicity is the support it has garnered from one of the United Kingdom’s most esteemed maritime locations, the Falmouth Wharves, which houses Oceanus 2. The Falmouth Wharves has been a strategically and historically important site, from its 18th century naval beginnings to its present role as a commercial maritime resource (8).
At present, ocean energy only covers around .02% of European energy needs, and the industry has several gaps to close before attaining a clear path to widespread implementation (9). While the United Kingdom and Scotland have taken the lead, Portugal had three machines installed as well in its Agucadour Wave Farm. However, due to technical problems, the facility was shut down only two months later, demonstrating the need for further research and improved engineering (9). Despite this setback, the European Union has maintained its goal made in 2008 to install 25 additional machines that will create an energy farm generating ten times the amount of energy as the devices at present. For years, wave energy has faced issues with investors, who are much more willing to invest in the better researched, more widespread wind and solar energy sources. Despite the ubiquity of waves, it also presents a mathematical challenge, which makes investors less likely to trust the feasibility of a widespread plan more cost-effective than other popular renewable energy solutions. George Hagerman, research associate at Virginia Tech University’s Advanced Research Institute, explained, “With wind, you’re harnessing the energy as a function of the speed of the wind. In wave energy, you’ve not only got the height of the wave, but you’ve got the period of the wave, so it becomes a more complicated problem” (10). This added factor inhibits the feasibility of the planning phase, the period in which investor backing is crucial.
Australia has made a breakthrough in wave energy technology with the knowledge that its southern shores were extremely conducive to generating electricity. According to the Australian Renewable Energy Agency, Australia’s Carnegie Wave Energy Project set a new world record in early June of this year after completing 14,000 cumulative operating hours, provided by $40 million in funding the cost of the project (11). Carnegie Wave’s technology was the world’s first line of wave power generators to connect to an electricity grid—ideal for a country with around 80% of its population living on the coast. In a study entitled “The potential of wave energy” by Hayward and Osman, much of the world’s coastal waters that have the wave power densities great enough for extracting wave energy are found on Australia’s southern coastlines and Tasmania’s western shore (12). Using what the journal article called the “levelised cost of electricity” based on wave energy convertor and Australia resource data, wave energy in those locations could be as low as $100 per megawatt hour. The major costs the study found involved operational ones like anchoring and mooring, as well as minimizing risk from aggressive storm waves. Australia’s government recently declared its intention to have wave energy supply at least 5% of Australia’s total grid by 2050 (12).
Marine institutes and university departments have expressed concern over implications for marine life around wave farms, which would need to take up substantial space given current plans and mechanisms to provide enough energy to render the projects worthwhile. According to the Northwest National Marine Renewable Energy Center at Oregon State University, wave energy converters reduce the amount of ocean energy in near-shore waters. This factor, in addition to the physical one of having large objects lodged throughout coastal ecosystems, can change current patterns and water mixing, thus introducing foreign species and clearing out others (13). It can also shift food delivery patterns and rates, tamper with egg and sperm mixing, disperse spores and larvae, and vary temperature differently throughout the water depth column. On the one hand, this tampering with ocean environments can severely disrupt the ecosystems of the offshore organisms. On the other hand, though, the energy center acknowledges that the eventual adaptation of the wave energy devices into the ocean environments can provide artificial reefs for creatures whose natural habitats have been largely destroyed.
Wave energy no doubt has serious potential for providing electricity in coastal areas around the world. Funding, support, and ingenuity in recent years have inspired vastly different types of convertors and methods of improving upon them, demonstrating promise of adaptability and perhaps catering different devices to different regions based on feasibility. Despite the enormous amount of potential energy in waves, with astounding numbers claiming to be able to power entire countries, the actual convertible energy in the current models remain quite small. Wave farms in the ocean provide the benefit of not intruding upon land in the way we see wind farms and solar devices, but storms also complicate feasibility and risk financially devastating damages. Without a method of consistency among the different types of wave converters, it may be difficult to determine which of the models can be standardized and cheaply made for widespread use. Nonetheless, leading companies remain optimistic of the potential for wave energy and have given reason in recent years to believe that the industry is rapidly expanding and improving. If wave energy companies can meet projected rates of conversion to usable energy per wave and do so in an economic way, that could seriously challenge other contenders in the renewable energy field.
(1) Hayward, Jenny and Peter Osman. “The potential of wave energy.” Garnaut Review. CSIRO Energy Transformed Flagship Ltd., 2011. Web. 4 August 2016.
(2) Fecht, Sarah. "Wave Power: 5 Bright Ideas to Capture the Ocean's Energy." Popular Mechanics. Hearst Communications, Inc., 05 Apr. 2011. Web. 04 Aug. 2016.
(3) "Introduction to Ocean Energy." European Commission for Research and Innovation: Energy. European Commission, 2015. Web. 4 Aug. 2016.
(4) Smith, Sarah. "Wave and Tidal Energy Market - Global Industry Analysis, Size, Share, Growth, Trends, and Forecast 2016 - 2024." PR Newswire. PR Newswire Association, LLC, 2 Aug. 2016. Web. 03 Aug. 2016.
(5) "Current Funding for Ocean Energy.” European Commission for Research and Innovation: Energy. European Commission, 2015. Web. 4 Aug. 2016.
(6) “Scotrenewables Tidal Power." The European Marine Energy Centre. The European Marine Energy Centre Ltd., 2016. Web. 4 Aug. 2016.
(7) Ewens, Graeme. " Insight for the European Commercial Marine Business." Maritime Journal. Mercator Media Ltd., 28 July 2016. Web. 03 Aug. 2016
(8) Ewens, Graeme. "Deepwater wharves safeguarded for marine usage.” Maritime Journal. Mercator Media Ltd., 28 July 2016. Web. 03 Aug. 2016.
(9) Gleich, Amy. "Five Companies Riding the Wave of Ocean Energy." OilPrice.com. Merchant of Record: A Media Solution, 02 Aug. 2014. Web. 04 Aug. 2016.
(10) "Technical Background of Ocean Energy.” European Commission for Research and Innovation: Energy. European Commission, 2015. Web. 4 Aug. 2016.
(11) Hill, Joshua S. "Australia’s Carnegie Wave Energy Project Sets World Record." CleanTechnica. Sustainable Enterprises Media, Inc., 02 June 2016. Web. 03 Aug. 2016.
(12) Hayward, Jenny and Peter Osman. “The potential of wave energy.” Garnaut Review. CSIRO Energy Transformed Flagship Ltd., 2011. Web. 4 August 2016.
(13) "Effects on the Environment." Northwest National Marine Renewable Energy Center. Oregon State University, 2016. Web. 03 Aug. 2016.
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