Alternative Energy - Tidal Power: Canal will be a proving ground for tidal turbines - by Steve Maas

For about a quarter-million dollars, a nonprofit research organization will build a modest test facility at the Cape Cod Canal that may help prove that producing electricity from ocean currents can be commercially viable.

The Marine Renewable Energy Collaborative will soon install the nation’s first permanent facility to evaluate submerged turbines that generate electricity from tidal power, in 25 feet of water at the west end of the canal, near the Buzzards Bay Railroad Bridge.

The simple trestle-like stand will make it vastly easier — and less expensive — for companies and researchers to subject their prototypes to real-world conditions.

“There is no standard test for tur bines, making it hard for generating venture capital,” said the collaborative director, John Miller. “There are a number of companies we know of that have designs they’d like to commercialize.”

Currently, makers of tidal turbines have to lease a ship to bring their equipment to an offshore location or build their own site along the shoreline. Either option is expensive and requires a lengthy permitting process to show the test site won’t adversely affect the marine ecosystem.

“Early experience was that about 70 percent of the cost of an ocean demonstration was just the permitting,” Miller said.

Much touted over the past few decades, tidal power has been slow to show its promise in the United States.

There are large projects underway in Canada, in the Bay of Fundy, and in Europe, off the coasts of Ireland, Scotland and France. Those have public funding, subsidies, and favorable geography — rugged coastlines, where tides rush in and out of narrow channels.

But nearly all of the ideal US locations fortidal power are in Alaska, said Robert Thresher, a fellow at the US
National Renewable Energy Laboratory who specializes in offshore power
technologies.

“It’s kind of a stranded asset,” Thresher said.

In far northeastern Maine, Ocean Renewable Power Co. is moving forward with its second tidal project in Cobscook Bay, where tides rise and fall some 20 feet over a 12-hour cycle. In 2012, the company deployed the first — and so far only — tidal energy project to deliver electricity to the nation’s power grid. The four turbines in the TidGen power system supplied enough electricity for 25 to 30 homes.

The $21 million project served as “primarily a learning tool, a way to verify that our design works,” said Chris Sauer, president of the Portland, Maine, company.

Sauer is developing a second-generation TidGen that he said would have four times the generating capacity and be less expensive to deploy and maintain. The company has a long-term contract with Maine utilities to supply up to 5 megawatts of power.

The cost of installing the first of the new units will be $5 million, Sauer said, and he hopes to complete fund-raising by this fall; the remaining turbines will cost another $35 million. Installation would begin in late 2017, at the earliest.

Whenever you’re dealing with new technology, it always takes longer and costs more money than you think,” Sauer said.

He projected that power from the tidal system would cost 25 to 30 cents a kilowatt hour. That’s expensive compared to more conventional electricity sources, but Sauer said that if the demand for turbines increases, economies of scale could make tidal energy competitive. His company has set its sights on foreign markets and, like Littoral, on Muskeget Channel.

Unlike solar and wind power, tidal energy is incredibly predictable, literally for hundreds of years,

Read more: Canal will be a proving ground for tidal turbines - The Boston Globe

Alternative Energy: 0cean Tidal Power: Can a Small Maine Town’s Innovation Turn the Tides on Sustainable Energy?

The sun rises early in Eastport, Maine – it’s the Eastern most city in the United States – and while the streets are quiet, fishing boats set out for the day. And reliably, these massive tides are flowing in and out, just as they have twice a day, every day for millions of years.

And it’s that fact, that predictability that people in this corner of Maine believe could change the face of America’s energy future over the next couple of decades.

Read more: Can a Small Maine Town’s Innovation Turn the Tides on Sustainable Energy? | PBS NewsHour | Sept. 15, 2013 | PBS

Alternative Energy: First US tidal power project headed for next stage-by Tim Cox

About two hours is all one needs to witness the dramatic difference in the tidal waters surrounding Eastport, and like other coastal Maine communities, the difference between high tide and low tide can be sweeping.

At about 12:30 p.m. Monday, vast mudflats lay uncovered by the ebb tide. A family was gathered on the mudflats near the entrance to the town, apparently digging for clams.

Barely two hours later, those acres upon acres of mudflats were submerged by the incoming tide.

It is the energy behind the flowing tidal waters that Portland-based Ocean Renewable Power Co. seeks to harness and convert into electricity.

The company’s pilot project to accomplish that task has been underway about a year with a deployed a turbine generator in Cobscook Bay, to the west of Eastport, producing electricity as the incoming and outgoing tide pushed the foils of a device.

The company removed the turbine generator — resembling a rotary lawnmower with a generator in the middle — last month for a yearly inspection, maintenance and service. It sits at the facilities of The Boat School in Eastport, a wooden scaffold erected around it to make it accessible to workers.

It is the first commercial pilot project in North America that converts the power of the tides into electricity and connects to the energy grid. When operating, it generates enough electricity to provide power to about 25 homes.

The company has been learning from the yearlong project and is moving forward to phase two — the deployment of two more devices in 2014.

Read more: Tidal power project headed for next stage — Down East — Bangor Daily News — BDN Maine

Alternative Energy: Tapping into the power of the sea brought to a halt by David Cameron in Britain

In Great Britain and other European countries, companies are preparing to use the energy of ocean waves and tides to produce electricity. The UK is hoping to produce as much as 5 percent of its electricity needs with tidal power plants.

Great Britain had hoped to soon be able to take the global lead in tapping the power of tides and produce clean energy. This single power plant was expected to cover 5 percent of the country's electricity needs by providing 8.6 gigawatts of CO2-free electricity, the equivalent of about eight nuclear power plants -- but without the pesky waste.

The tidal range at the mouth of the Severn, Britain's largest river, is 15 meters. The previous British Labour government of Gordon Brown had wanted to put this enormous force to use with its Severn Barrage project. The barrage was planned to hold back water at high tide like a dam, and 216 giant turbines -- each about 9 meters in diameter -- and to be powered up as the water ebbed.

Tidal power could also be put to good use in Germany, argues Kai-Uwe Graw, a professor for hydraulic engineering at the University of Leipzig. Graw says sufficient flow velocities -- around three meters per second is optimal -- can be found on parts of the island of Sylt near the German-Danish borner.

Graw began raising awareness about tidal power's potential back in the 1990s. In his opinion, tidal power plants can easily be compatible with coastal conservation efforts. One benefit is that the facilities extract some of the energy from tides, which could help to reduce the kind of beach and coastal erosion that has been a major problem for Germany on North Sea islands like Sylt in recent years.

Unfortunately the new British Conservative government of David Cameron sounded the death knell for the world's largest tidal energy project – to be built across the Severn estuary between Somerset and south Wales – when it recently ruled out the use of public funding for this, what they considered,  controversial euro 23B plan.

The announcement obviously pleased some environmentalists, who were worried about the impact on bird life in the estuary, but others say such spending cuts made a mockery of David Cameron's pledge to be the "greenest government ever".

For more: EU-Digest