Our Crowning Glory?

Offshore energy means more than just oil and gas. But is it an energy nirvana or a cult of false hope? Bruce Nichols looks at the progress that the marine renewables industry has made, and the hurdles it has to overcome.

The latest trend in renewable energy has come to Cobscook Bay in Maine, on the US/Canada border. On the bay bottom, a turbine driven by tidal ebb and flow is generating electricity for customers onshore. The facility built, installed and run by Ocean Renewable Power (ORPC), is the first in-stream, tidal generator in North America to go commercial.

“We’ll take bragging rights for the Western Hemisphere,” says John Ferland, vice president of project development for ORPC, which has had its 150kW TidGen system selling power into the grid since last September and plans expansion to as much as 5MW capacity by 2017. Project cost is $20 million, including $10 million provided by the US Department of Energy (DOE).

The innovative ORPC turbine is just one example of a surge in ocean energy research and development that took off in Europe a decade ago and is spreading globally. New devices are capturing wave as well as tidal energy, and, more exotically, engineers are studying extraction of power from variations in ocean temperature and salinity.

Ocean Renewable Power’s tidal turbine about to be lowered into the water in Cobscook Bay near the US/Canada border in Maine. The turbine rated at 150kW has been selling power to customers onshore since last September. It is the first commercial in-stream tidal power generator in North America. Two more turbines are set to be installed this year in a project costing $20 million, half of which came from the US Department of Energy.

Not that mankind is on the verge of energy nirvana, cautions Neil Kermode, director of the European Marine Energy Center in Scotland. His test facility is part of the UK’s world-leading ocean energy program, but he is careful not to exaggerate growth. “Explosion is probably an overstatement,” he says. “It’s a bit of a mushrooming; in the dark, quite gentle, and often unexpected.”

Ocean energy

Actual marine hydrokinetic power production – that’s the term experts use to distinguish it from wind and more familiar, river-based, hydroelectric power – remains small relative to demand. Marine hydrokinetic power contributed about 0.1% of total world demand in 2010, representing less than 1% of all renewable output, according to the International Energy Agency.

Government support is still crucial because costs are high. ORPC, for example, gets a state mandated US$0.215/kilowatt-hour (kWh) in Maine, compared with a state retail average of less than $0.15/kWh. Non-energy priorities like the environment, fishing and shipping must be accommodated. Steps forward currently seem to outnumber steps backward, but prototypes still fail, private investment is hesitant, and the world fiscal crisis threatens government funding.

Even boosters of ocean energy say it will take decades to unfold – the IEA sees it becoming significant in 2030 – and it won’t work everywhere. The best tidal energy sites are at high latitudes, like Maine and Scotland, where tidal range can equal or exceed 20ft, compared with a foot or less at the equator. The best wave energy sites are in places with long, west-facing coasts beside broad oceans. Local power prices need to be high, as in Hawaii, where rates can reach $0.30/kWh. The continental US average is $0.12/kWh.

Still, the potential is enormous. A recent DOE study says waves and tides theoretically could provide 1420 terrawatt-hours (TWh) of electricity, a third of the 4000TWh consumed annually in the US. The practically recoverable is smaller, less than 15% of consumption by 2030, when it would still be a junior partner to onshore hydropower, DOE says.

Parallel development

Since 2000, ocean energy technology has built rapidly on progress in other fields, including offshore oil and gas: the development of heavy lift vessels that can launch huge turbines; better corrosion control and coatings to keep marine life from fouling equipment; stronger, lighter construction materials from the aerospace sector; electronics and software from Silicon Valley.

“It’s only recently that technology gained from offshore industries like oil and gas have evolved to the point that it’s actually reasonable to think about putting these converters out in the marine environment to harness this power and realize theoretical designs,” says Brian Polagye of the University of Washington, co-director of the Northwest National Marine Renewable Energy Center.

Advances in computing power and software are key to the first grid-connected wave power buoy on the US West Coast, set for launch this spring. The ‘secret sauce’ in Ocean Power Technologies’ PB150 is its electronic brain, says Phil Hart, OPT’s senior vice president. It tunes the buoy to the surrounding wave regime, maximizing power output in normal seas and survivability in rough ones.

“You’re connecting a very variable input to a generator and trying to, on average, optimize generator speed and force to maximize its power output,” Hart says. “The absolute key to wave energy technology, therefore, is software control theory.”

Other US ocean renewable energy leaders include Verdant Power of New York, which hopes to begin installing a 30-turbine tidal system in the East River off Manhattan starting in 2014, using its fifth-generation design. In the Pacific Northwest, Snohomish Public Utility District – a big utility despite its unassuming name – has a tidal turbine plan for waters near Seattle. Columbia Power Technologies is working on a wave-power machine for the Oregon coast.

Ocean Power Technologies plans to install its PB150 PowerBuoy in the Pacific Ocean offshore of Oregon this spring. The device (seen above during a test in Scotland) is rated at 150kW and will be the first wave-riding power-generating buoy connected to the US electric grid with plans to sell the power to onshore utilities. The device stands 9m tall out of the water, but its lower section extends 26m underwater, for a total height of 3m.

“The military wants to put sensors and listening devices into the ocean to detect submarines, ships, swimmers. Oil and gas applications are very similar. You can feed the umbilical and mooring down to the seabed, leave it for up to three years and use it for anything. Think of how many things you want to sense in the ocean.”

The idea is not entirely new to the offshore oil & gas sector. Anadarko Petroleum has been studying the generation of power from ocean currents for several years and successfully tested a one-fifth scale device in 2011, though it has not put it to commercial use.

Overall, last year was a “banner year” for ocean energy, says Mike Reed, who runs the US Department of Energy’s water power program. Since 2009, some 26 projects have received more than $100 million in funding, which must be matched with funding from other sources. Among them is a planned US test center modeled on Scotland’s EMEC. The US Federal Energy Regulatory Commission (FERC) and the Bureau of Ocean Energy Management have streamlined their rules to accommodate ocean energy.

The surge in activity is due in large part to the US enacting the Energy Policy Act of 2005. Prior to that, marine hydrokinetic energy was not even listed among renewable projects eligible for federal money. The change has stirred private interest.

“When FERC opened the permitting process, it was kind of like the gold rush,” Reed says, though he notes preliminary permits far outnumber actual projects. “Companies were staking out territories for future developments. To me that was a very positive indication.”

The move by ORPC, OPT and others toward commercialization is a big step forward, says Chris Campbell, executive director of Marine Renewables Canada, an advocacy group that includes private, public and nongovernmental organizations.

“This momentum is beginning to focus on trying to demonstrate a power plant as opposed to a technology, and to my mind that is the big transition that has been happening in the last 12 to 18 months,” Campbell says.

MeyGen is planning a 400MW tidal generation project in Pentland Firth, Scotland. The project, shown in this artist’s depiction, is one of 11 planned by the UK for the area by 2020 with a total capacity of 1600MW (a test turbine is pictured bottom). The UK has embarked on an aggressive path to develop ocean energy and is currently the world leader in the field.

UK initiatives

US efforts remain a far cry from work in the UK, where coordination between government, industry and academia has become a motive force much stronger than often fractured US funding, permitting and development processes for ocean energy, says Polagye.

In its latest major move, the UK created two huge marine energy parks last year, one off Cornwall in the southwest and another off the north of Scotland, setting aside offshore waters for renewable energy development.

Not far from Kermode’s office at EMEC, the world’s largest tidal energy project is planned in Pentland Firth, one of the best sites anywhere for underwater turbines because of its dramatic tides. The UK hopes to have 1600MW of tide and wave-generated electricity operating in the Firth and around the Orkney Islands within a decade, at a cost of more than £6 billion.

‘Our goal is still 2014 for installing a demonstrator array. We are hopeful of being able to build out the rest of the project before 2020,’ says CEO Dan Pearson of MeyGen, which plans a 400MW installation, the largest of 11 projects given government leases in the Pentland Firth area.

Major multinational equipment manufacturers are diving in, buying or investing in startup companies in wave, tidal and other forms of ocean energy, and that’s a big change, Kermode says, touting EMEC’s 14 test berths and additional offshore sites where many devices can be demonstrated at the same time.

“We have been able to act as something of a shop window, which I’m sure has helped generate confidence,” he says.

Within the past 18 months, Germany’s Siemens has bought Marine Current Turbines. France’s Alstom has taken control of Tidal Generation. French oil major Total, Swiss engineering giant ABB, US aerospace giant Lockheed Martin and Japanese industrial giants Kawasaki and Mitsui also have ventured into the sector.

Other nations are following the UK lead in ocean energy. Japan has stepped up activity in the field since its Fukushima nuclear disaster forced reevaluation of its energy supply. Australia, New Zealand, South Korea, and China, seeking alternatives to fossil fuels, are heavily engaged. In South America, energy-short Chile, with its 4300km (2700 mile), west-facing Pacifi c Coast, is beginning to look at opportunities.

The effort could still falter in the US, which differs in key ways. The UK is an island nation, has a stronger sense of vulnerability to high energy costs as well as wider public acceptance of climate change than the US, says Oregon State University’s Belinda Batten, co-director of NNMREC with Polagye.

Generally low US electricity prices, thanks to relatively inexpensive hydropower and the boom in natural gas, is a market challenge for ocean energy, adds Damian Kunko, a Washington lobbyist for the Ocean Renewable Energy Coalition. “It’s an issue of cost,” he says.

Even US president Barack Obama, who has repeatedly called for renewable energy development, recommended cutting funding for water power programs by two-thirds in his 2013 budget, seeing wind power as a surer bet in a fiscally constrained world.

Optimisim

But given a growing desire for alternatives to fossil fuels and that half the US population lives near the coasts, within relatively easy reach of ocean energy, there is reason to be optimistic, according to Trey Taylor, co-founder of Verdant Power.

“It’s slow going because of the economy, because of vested interests, but we’re getting traction, we’re making progress,” Taylor says. “It is slower than we wish it would be, but it’s inevitable.” OE