Ocean energy can play important role in renewable resources mix

June 25, 2011 by admin  
Filed under Ocean Energy

Renewable technologies could supply the world with more energy than it would ever need and at a very competitive cost, avers Steve Sawyer, secretary-general of the Global Wind Energy Council.

He adds that ocean energy may play a very important role in the future. Ocean energy derives from the potential, kinetic, thermal and chemical energy of seawater, which can be transformed to provide electricity, thermal energy or potable water.

According to the Intergovernmental Panel on Climate Change (IPCC) report published recently, several technologies are possible, such as submarine turbines for tidal and ocean currents, heat exchangers for ocean thermal energy conversion, and a variety of devices to harness the energy of waves and salinity gradients.

Ocean technologies, with the exception of tidal barrages, are at the demonstration and pilot project phases and many require additional research and development. Some of the technologies have variable energy output profiles with differing levels of predictability (for instance, wave, tidal range and current), while others may be capable of near-constant or even controllable operation (for instance, ocean thermal and salinity gradient).

Tidal Power Plant in Northern Ireland
Sabine Sauter writes in Pictures of the Future about “tapping invisible rivers”.  Tidal flows represent a largely untapped source of clean energy.

Located off the coast of Northern Ireland, the world’s first commercial tidal current power plant is producing electricity for 1 500 household using energy generated by high and low tides. The Strangford Lough plant is operated by Marine Current Turbines, a British company in which Siemens acquired a 10% interest in 2010. The facility is similar to a wind turbine, the only difference being that it is driven by water instead of air. Each of its two drivetrains weighs 27 t and is equipped with a rotor 16 m in diameter.

The rotor blades can be turned through 180º, which means they can produce electricity for up to 20 hours a day regardless of whether the tide is coming in or going out.

The tower to which the two propeller turbines are attached through a cross member has a diameter of 3 m. Depending on the tide, the tower can protrude as much as 20 m above the sea. The rotors cannot be seen above the water – and it is even possible to take a small boat directly past the turbine because the rotors are located at least 3 m below the surface.

Although extensive installation costs make an investment in tidal current power plants around twice as high as those for offshore wind power facilities, the resulting electricity offers several benefits. For example, the energy density of water is 800 times higher than that of wind, which makes gene- rating electricity with water much more efficient. A 1,2 MW tidal plant like the one at Strangford Lough can produce as much electricity in a year as a 2,5 MW offshore wind turbine. The electricity yield from tidal facilities is also more precisely calculatable, which enhances planning security. After all, tidal currents are determined by the moon and the earth’s gravity, so they are not dependent on the weather and can be predicted years in advance.

The International Energy Agency estimates the global output potential of tidal power plants to be as high as 800 TWh/y, which is enough to supply 250-million households with electricity.

Marine Current Turbines continues to invest in tidal technologies. Besides other things, the company plans to start building a tidal turbine park near the Isle of Skye, in north-eastern Scotland, in 2013.

When it is complete, the facility will supply up to 4 000 households with electricity from the sea.

Article source: http://www.engineeringnews.co.za/article/ocean-energy-can-play-important-role-in-renewable-resources-mix-2011-06-24

On the path to clean energy

June 25, 2011 by admin  
Filed under Ocean Energy

The Southeastern Massachusetts region is positioning itself as a serious player in the growing clean energy industry, working to build an active supply chain for clean energy developments, even as the industry itself struggles to build momentum.

A recent clean energy study put Massachusetts third overall in the country in terms of clean energy development and, while the state’s southeast region may not be the driving force for that ranking, it also doesn’t plan to be left out.

“Conversations have begun with companies not just in the offshore renewable space, but in solar or whatever,” said Matthew Morrissey, executive director of the New Bedford Economic Development Center. “New Bedford is on the map as a player in a space that a lot of companies want to be in right now.”

While Morrissey and other city and regional officials are working to have multiple renewable energy resources represented, the biggest success to date has been in offshore wind energy with the city’s selection as a staging area for Cape Wind.

In fact, much of the anticipated regional growth hinges on the fortunes of the country’s first fully permitted offshore wind farm, a project that has faced numerous hurdles, but may still get in the water in 2012.

Although facing litigation and without financing, Cape Wind spokesman Mark Rodgers said the 130-turbine project expects to begin installation next year. At a June 16 Council on Sustainability meeting in Fall River, Rodgers didn’t seemed concerned about litigation, calling efforts “the last play of our opposition;” but, said securing financing has been difficult.

“(Financing) is a major challeng-It’s going to take some time and effort,” he said.

Rodgers said the New Bedford staging area, a $35-million port facility to be built on the city’s waterfront, needs to be ready in time for Cape Wind installation.

That won’t be a problem, according to Morrissey, who said the project is in the engineering stage and ground is expected to be broken this fall.

“That project is moving forward,” said Morrissey. “We’re much more concerned with Cape Wind’s need to finalize their program…The remaining 50 percent of power has to be worked out as well as financing.”

The port facility, on New Bedford’s active waterfront, will do more than just help the city get its foot in the clean energy door, it will also let the city leverage its working port, boosting its import and export trade business, according to Harbor Development Commission director, Kristen Decas.

Decas said the city is also tracking other offshore wind developments along with tidal energy keeping an eye on how the port can play a role in supporting development.

“We’re a sleeping giant and we have huge room for using this asset,” said Decas, about the harbor. “This facility will put us on the map for a variety of future opportunities in offshore energy development.”

Middleboro manufacturer, Mass Tank, will also benefit from offshore wind project, shifting its past expertise building steel tanks for the oil industry into building monopoles for wind turbines. Mass Tank, through its ECO Fab partnership, will build a new manufacturing plant, to supply steel structures to Cape Wind and other offshore wind developments. The plant is expected to employ at least 300 people.

Although the specific location of the facility is unknown, reports have suggested both Quincy and New Bedford are in the running.

According to Morrissey, opportunities for Mass Tank still exist in New Bedford but the decision will depend on whether or not the city can provide a site that meets Mass Tanks’ specific needs.

“They’ve been very clear all along, they would like to be in New Bedford,” Morrissey said in mid-June. “They’re from here; they’d like to be here and it is less expensive to do business here. The question is that the characteristics of the site that is required for the activity are not immediately available.”

While other industries continue to grow in the state, including solar which increased 20-fold between 2007 and 2010 according to Mass CEC, Massachusetts’ clean energy future may depend on offshore wind, according to some experts.

Offshore wind may be the state’s best resource or at least the best one that is technologically ready for implementation, according to Ron Pernick, co-founder and managing director of Clean Edge, an Oregon-based clean-tech research firm.

Pernick said Massachusetts is at a geographic disadvantage when it comes to producing renewable energy, compared to other states that have heavy wind or lots of sun.

“Massachusetts doesn’t have the wind resources on land like these other places,” said Pernick, citing states like Iowa and North Dakota, which are producing 15.4 percent and 12 percent of their electricity through wind respectively.

In Clean Edge’s leadership index, released in May, Massachusetts got high marks in categories like policy, venture and human capital, and clean energy patents, but still scored in the lower half of the country when it comes to energy production.

The state placed third overall, below California and Oregon.

The production category represents technical deployment including how much wind power, solar, biofuels, geothermal and other energy sources are in use, as well as the number of electric vehicles on the road, according to Pernick.

Still, Pernick, said, the Cape Wind project has the potential to change everything for the state.

“If you bring the Cape Wind project online, if you develop offshore wind and tidal energy, you’ll see yourself move up,” he said, referring to the state’s positioning.

And, while offshore wind is new to the state, it isn’t a new technology. There are more than 40 offshore wind farms off the European coast, according to Rodgers.

That’s different from ocean energy which is a relatively untested technology, Pernick said.

“I think, over time, wave and tidal energy offer significant promise, but I think it’s further out than a five year timeline,” he said.

At the Marine Renewable Energy Center in New Bedford, director John R. Miller believes ocean energy, including offshore wind, is the state’s alternative energy future.

“I always tell people that solar energy and biofuel are two things that are of great interest to venture capital people in Boston€but if you think of somebody who wants to build a big solar energy plant, they’re more likely to do it in Arizona or Spain where there’s a lot more sunshine,” said Miller. “If you look at what resource we actually have — the ocean is a resource that is literally on our doorstep.”

Miller said ongoing efforts to develop new ocean technologies, even if they are not created here in Massachusetts, will still need to be built and maintained locally. So it’s important that the region begin taking steps to develop a workforce and build a supply chain for the industry, he said.

Some of that is already happening through the Southeast Development Partnership, out of UMass Dartmouth, Miller said.

“They’re looking at all the pieces in the supply chain,” said Miller. “(Questions like,) what do we have now, what are we going to need in five years, and how can we convince the company who is manufacturing cables, for example, to locate in the Southcoast?”

While offshore wind may be the state’s bright future, it is also one of the most controversial forms of renewable energy, along with land-based wind, according to David McGlinchey, of the Manoment Center for Conservation Sciences.

As senior program leader for energy, McGlinchey said he participates in many conversations about wind energy and development projects. He wants to lessen the controversy by helping projects strike a balance between energy benefits and environmental and quality-of-life impacts.

“The challenges from my perspective are not technical, they’re social,” said McGlinchey. “There are real benefits (to wind projects), but they also have an impact. The key is balancing that, finding appropriate sites that balance benefits and impacts.”

McGlinchey said the Manoment center is putting together a guide, to be released in September, to help municipalities create bylaws based on the science behind wind and their own local values.

“It will give them the tools they can use to build an effective bylaw,” he said.

Despite frequent wind opposition, McGlinchey said he believes people are becoming more supportive of renewable energy ventures.

“I feel very confident that (issues) can be worked out. I think we’re getting better at it,” he said. “The vast majority of people in these conversations inherently want to find solutions. The key is having a reasonable, informed conversation which is not easy.”

Rodgers too said public opinion has shifted in the last few years. Despite a slightly battle-weary tone, he spoke very positively about clean energy technology and its potential impact on the region.

“A sustainability cluster is starting to take shape,” he said. “We have the makings to be one of those clean energy global hot spots.”

Article source: http://www.southcoasttoday.com/apps/pbcs.dll/article?AID=/20110624/NEBULLETIN/107040301/1036