In this section we will consider several sites along the New England coastline that have conditions which are favorable for the construction of tidal power plants employing GHT technology. The main criteria for the selection of a prospective site is the presence of relatively large water flow through narrow channels leading into a substantial tidal basin. It is important for the mean tides to be high in order to develop the strong currents needed for efficient production of power from GHTs.

The following table identifies some New England sites that are suitable for construction of tidal power plants utilizing GHTs.

Site	Mean Tide, m.	Water area, sq. km.	Annual potential energy, GW-h	Projected power output, MW
Passamaquoddy Tribe	5.5	2.2	131	10, (might be much larger)
Treat Island	5.5	100	5840	360
Machias Bay	3.7	65	1730	180
Englishman Bay	3.7	750	750	80
Pleasant Bay	3.4	10	228	30
Gouldsboro Bay	3.3	25	520	60
Frenchman Bay	3.3	150	3220	400
Long Cove	2.7	25	350	60
Casco Bay	2.7	16	230	40

The Passamaquoddy Tribe location is one of the most studied in terms of the exploitation of tidal power, because it has a fairly large basin with a narrow and shallow entrance protected from open ocean storms. Mean tides of 5.5. meters, with maximums of almost 8 meters, provide very high energy density that should permit the production of power at very competitive costs. The unique conditions of Half Moon Cove have made this basin extremely attractive for tidal power development. Indeed, there have been numerous technical and economic feasibility studies on tidal power projects for this region which date back to 1919.

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In 1919 Dexter P. Cooper initiated a large-scale international project for the Cobscook Bay site.-In 1930-34, the Army Corps of Engineers constructed a housing development and causeway.

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In 1977 Stone and Webster Corporation prepared a tidal power study report to the U.S. Energy Research and Development Administration (“ERDA”)

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In 1978-82 the Corps conducted a study for the All-American Tidal Projects.

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In 1976 the Half Moon Tidal Project, initiated by the Passamaquoddy Tribe, proposed to install a small scale tidal power plant of 5 to 12 MW by 1985.

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In spite of the fact that a great deal of time and money have been spent on exploring the potential production of power from this area, there have been no worthwhile results. Each new effort to design a workable tidal project in this area has been terminated as a consequence of the huge capital investments which would be required for construction of a conventional hydropower system employing a massive ocean dam.

With the development of the GHT technology, which eliminates the need for dams for extracting power from tidal currents, the major obstacles to developing power from these tidal currents have disappeared. One or more tidal power plants using Gorlov Helical Turbines can now be justified economically for the locations identified above, especially for the Cobscook Bay area.

There are many other bays and river estuaries along the East coast that appear suitable for tidal power development using the GHT technology. Unfortunately, there is not sufficient tidal data on power production potential at these sites because the mean tides there are less than 5 meters, which is commonly recommended as the minimum tidal fluctuation for the conventional dam scheme. As a consequence of its beneficial characteristics, however, the critical criteria for power production using GHTs is the water velocity and not the height of the tide. From this point of view, most of the East Coast tidal currents are sufficient for power production using GHTs.

The very first testing of Gorlov Helical Turbines was performed in the tidal currents of the Cape Cod Canal in Massachusetts from June through August of 1996. The water current in the Cape Cod Canal is a typical tidal current characterized by reversing flow four times a day. The canal also has a substantial amount of floating seaweed. The maximum water velocity at the test site was measured at 5.6 ft/s. During the testing, the four different Helical Turbines tested never failed to rotate and generate power. The maximum efficiency of the GHTs tested was about 35% in a water current with a velocity of 5 ft/s. Based on these tests, one could conclude that tidal power stations from 40 kilowatts up to a few megawatts could be constructed in the Cape Cod Canal.

Another prospective site in this region for the installation of a power station using GHTs is in the ocean currents south of Cape Cod, between Woods Hole and Martha‘s Vineyard. Water current velocities there are in the range of 4 to 5 knots, which is sufficient for the design of a GHT driven power station with a capacity of about 10 megawatts.

The kinetic energy of ocean streams is enormous. The mass of water carried by the Gulf Stream in the Atlantic Ocean is many times greater than the water flow of all the Earth’s rivers combined. The energy potential of the Gulf Stream at this location is greater than any imaginable requirements for America. The conceptual design for a large-scale floating power farm in the Gulf Stream using GHTs is described by the author in the article “Helical Turbines for the Gulf Stream” [8]. Employing the approach described in this article, a moored modular power farm with 320 standard twin GHTs could harness about 210 megawatts from an ocean area of only 0.16 square km. Construction costs for such a marine power farm is estimated to be about $300 million, with an installed cost of about $1430 per kilowatt. This estimation was made using GCK Technology‘s new experimental industrial size twin GHTs, which are 2.5 meters tall and 1.0 meter in diameter. Once installed, the power farm could be expanded as needed in the future, since the potential of the Gulf Stream is practically unlimited. For example, one square mile of ocean surface in the Gulf Stream could generate about 5,500 megawatts using the described design.

Additionally, if the power generated from such a power farm were used for in-situ production of hydrogen fuel by electrolysis of sea water, it would be sufficient to supply hydrogen fuel for all of the automobiles in the U.S., if all the cars were equipped with electric motors using hydrogen fuel cells.

Passamaquoddy

Treat Island

Other sites of the Cobscook Bay region in Maine

Cape Cod Canal

Ocean currents in the Cape Cod and Martha’s Vineyard region

Phases of development

Investigation and selection of the site

Design, construction and monitoring of a 30-50 kW pilot project

Development of the full scale project

The Gulf Stream moored GHT power farm

Site selection near Miami and Key West Island

Development and testing of a 30-50 kW modular pilot project

Phase I: Construction of a 210 MW commercial GHT moored power station

Phase II: Extension of the power station

Phase III: Farther extension of the power station

Selection of sites where both water and wind power systems can be installed complementing and reinforcing each other.