Rising tide of optimism for tidal power

1 March 2007



Tidal energy capacity in the US and Canada may account for less than 5% of the world’s potential, but 20GW is prize enough for a group of sea power pioneers investing in a renewable alternative to fossil fuels. Chris Webb finds that, regulatory matters aside, energy from the oceans is beginning to make its mark


New York City’s East river may not seem the obvious venue of choice to site a pioneering renewable energy venture. But the Roosevelt Island Tidal Energy Project (RITE) is ideally placed to capture the minds and imaginations of the money brokers in the financial powerhouse that is the Big Apple.

The scheme, which developer Verdant Power predicts could set the scene for up to 10MW of locally generated power, lies in a narrow stretch of water between the island of Manhattan to its west and the borough of Queens on Long Island to the east. Stretching from Manhattan’s East 46th to East 85th streets and just 3km long, with a maximum width of 240m, Roosevelt Island is home to many foreign diplomats thanks to its close proximity to the United Nations headquarters. There will be no shortage of critics – and potential investors in similar technology –- keeping a watchful eye on the project’s progress.

Verdant is currently at various stages of development with four projects in four very different world markets: Canada; the UK; Brazil; and in the US. Other sites are currently under consideration in California, India and China. Using technology claimed to be years ahead of its rivals in ‘water-to-wire’ kinetic hydro power know-how, Verdant is one of a handful of a new breed of developers offering and implementing complete renewable, distributed energy solutions. The aim, the company says, is ultimately the delivery of conditioned power through the grid, or directly to end-users.

At the heart of the technology are two horizontal-axis turbine models – a 5m, 35kW generator system for tidal straits and a 2m, 10kW system designed for shallower rivers and water flows. By deploying the free-flow turbines in the river’s bed and arrayed in underwater fields in a similar fashion to typical wind turbine arrangements, they can generate utility and village-scale electric power from natural and predictable river currents.

Last December, Verdant installed the first two of six units that will comprise the world’s first free-flow tidal turbine field in the East river. One of the units, a 35kW rated turbine is, the company states, now providing reliable emission-free electricity with minimal effect on fish or the marine environment detected to date.

It has taken Verdant nearly five years and more than US$7M to reach this point. Most of the costs were in obtaining regulatory approvals for the demonstration project, while more than US$2M has gone on fish monitoring equipment and further investment is earmarked for analyses and more fish studies over the next 18 months as the company prepares its final permit and license applications for commercial operations.

The technology has many attractions. Unlike traditional hydro schemes, such systems do not require water impoundments and use minimal civil works, a consideration that itself virtually eliminates any adverse visible footprint the technology may have, with consequently low regulatory costs. By starting its first US project in New York City, conceivably the toughest US regulatory environment imaginable, Verdant Power has set a goal of becoming the industry’s self-styled trail blazer in changing the regulatory process and setting its standards. It is a bold initiative, particularly as the regulatory framework for the development of tidal and wave energy technology is in its infancy.

Regulatory process

The Federal Energy Regulatory Commission (FERC) regulates the licensing process for water power projects in the US and, as Michael Murphy, of Devine Tarbell & Associates (DTA), a regulatory specialist serving clients in the hydro power industry explains, this is also the case for tidal and wave energy projects. RITE is the first project of its kind in the US to traverse the FERC licensing process.

DTA was selected as the lead consultant for permitting and licensing of the project. It was the company’s job to support the preparation of all applicable permit applications for deployment of the initial pilot study consisting of six units and is supporting the ongoing collection of field data this year. In addition, it is overseeing the various environmental assessments, including velocity and bathymetric profiles, underwater noise evaluation, three-dimensional acoustic fish monitoring and effect of project operations on diving birds.

Murphy explains how the regulatory process works: ‘In accordance with the Federal Power Act (FPA), construction and operation of non-federal hydroelectric projects in the US requires a licence issued by the FERC. A FERC licence is the approval necessary to develop and operate a hydroelectric project in the US, and will have a term of 30 to 50 years. Within this license, state and Federal resource agencies can include mandatory or recommended conditions that provide for the protection, mitigation, and enhancement of fish and wildlife and their habitats.’

Until relatively recently, Murphy says, all projects under FERC jurisdiction fell neatly into the profile of a traditional hydroelectric project. ‘However,’ Murphy continues, ‘tidal in-stream energy conversion devices are designed to capture energy from in-stream tidal flows to generate power, while wave energy conversion devices generally use energy contained within the vertical motion of waves to generate power. Unlike the traditional hydroelectric generating facilities, these wave and tidal energy conversion projects do not have a rich history by which to guide jurisdictional authority and regulatory procedures [ie. permitting, licensing, consultation].’

Murphy says this relatively new area of hydroelectric power generation is developing momentum at an increasingly rapid pace, and FERC and other relevant Federal agencies have been presented with several opportunities to assert their jurisdictions and interpret regulations within the statutory authority granted by the FPA, the Energy Policy Act of 2005, and other authorising statutes.

As a result of a 2003 FERC order, tidal and wave energy projects to be deployed in waters of the US now fall under the jurisdiction of the Federal body, and therefore require a licence or exemption prior to deployment. More recent FERC rulings have defined the requirements for obtaining a licence or exemption prior to the deployment of units for study purposes. In a yet later order designed to give clarification, FERC concluded that a licence is not required for testing underwater turbine units if an applicant meets certain criteria. Namely, the technology in question must be experimental; the proposed facilities must only be utilised for a short period of time for the purpose of conducting studies necessary to prepare a licence application; and the project must have no net economic impact on the national electric grid or interstate commerce.

As if the regulatory waters were not turbulent enough, they are muddied still further by another recent development in the guise of the Energy Policy Act (EPAct) of 2005, signed into law by President Bush in August 2005. Murphy explains: ‘This authorised the Department of Interior, through the Minerals Management Service (MMS) to grant leases, easements or rights-of-way on the Outer Continental Shelf (OCS) for the development and support of alternative and renewable energy projects, including wave and tidal energy. It also authorises MMS to act as lead agency for coordinating the permit process with other Federal agencies.’ What it means is that the MMS now has the authority to regulate or permit the activities that occur on those leases, along with easements or rights-of-way, if those activities are energy-related. The OCS is defined as all submerged lands seaward of each State’s jurisdiction - typically three nautical miles from shore.

‘In order to implement its new regulatory authority, MMS must issue a regulatory framework outlining a programme for how it intends to handle these new types of projects. MMS is currently in the process of developing this regulatory framework. How MMS and FERC will resolve their respective jurisdictional responsibilities on the OCS is yet to be determined,’ says Murphy.

In general, however, this new programme will establish a regulatory framework designed to permit renewable energy development within the OCS in a way that balances competing and complementary uses of offshore acreage. It ensures consultation with affected states and local governments; takes into account the evolving nature of the energy industry; and provides a fair return to the US as well as coastal states for access to the OCS.

A new framework

Regulatory matters remain an issue to which a resolution is being sought by a number of agencies. Among them is the Ocean Renewable Energy Coalition (OREC), a national trade association for hydrokinetic and marine renewables, which espouses a new regulatory approach is essential to assist in the development of emerging technologies that were never contemplated when the Federal Power Act was enacted in 1920.

It proposes a new framework for the licensing of these technologies; one that it says will foster innovation and build a competitive industry that can help the US capture the benefits these technologies offer.

OREC’s proposed licensing and permitting framework consists of a number of interrelated and interdependent features, including: a programmatic assessment of technology; an eighteen month licensing process, from filing of notice of intent to submit an application (NOI) to approval by FERC; formalised cooperation between agencies, and a revolving fund to subsidise environmental studies, with subsequent repayment when funded projects sell power and, finally, incorporation of principles of adaptive management to bridge data gaps.

The framework also allows for the option of filing for a preliminary permit prior to initiating licensing. The eighteen month permit term would authorise the developer to study the site and provide an accelerated process to install test units. The permit would include firm milestones and could be renewed twice, at which point it is open to competition.

Renewables in general have assumed a greater importance in the US in recent years in the drive to minimise dependence on foreign oil and contribute to a diverse energy supply, and hydrokinetic, wave, tidal and current technologies provide an emission free source of power.

According to the US Energy Information Administration (USEIA) electricity generation is expected to nearly double between 2001 and 2025. Growth in the developing world will be approximately 50% greater than the worldwide average and it is expected that the economic, environmental and social factors that limit the growth of traditional hydro power will work to the advantage of small-scale hydro power. The electric-power-research-institute (EPRI) believes that ‘free-flow’, or kinetic hydro power systems could be hydro power’s answer to distributed generation, putting generation close to consumption.

All of this puts the RITE project into its proper perspective. The first set of tidal turbines deployed in 2006 is just the start for New York’s East river. While initial investments in the technology are relatively modest, even compared to other forms of renewable power, there are high hopes for it in the future. The East river, for example, could eventually host a field of underwater turbines with a capacity of up to 10MW. Verdant’s business partner is the New York State Energy Research & Development Authority (NYSERDA), which has invested more than US$2M to date in RITE. In the longer term, development of the technology in the state is unlikely to stop there. NYSERDA has identified a potential of more than 1000MW of capacity state-wide.

New projects

Though very much in the public eye, the East river project is by no means the only example of the tidal exploitation on America’s east coast. DTA has also assisted EPRI with environmental and permitting services for its Tidal In-Stream Energy Conversion Feasibility demonstration programme, which is intended to assess and demonstrate the feasibility of TISEC technology in providing efficient, reliable, environmentally-friendly, and cost-effective electrical energy. Work has progressed with the assessment of regulatory processes and environmental issues for potential sites in Maine, Massachusetts, New Brunswick and Nova Scotia. Possible environmental effects had to be considered from several project variables, including; installation activities, operation of a TISEC project, and the site and device-specific parameters. Site specific research was conducted by contacting the respective agencies to include discussions relating to: rare, threatened, and endangered species; commercial fishing; marine shipping channels or any other issues that could result in significant delays in the permitting processes or result in adverse environmental effects. A report discussing potential environmental effects related to specific devices including unique turbine mooring designs and water flow characteristics was issued in the spring of 2006.

On the west coast, it is estimated that the state of California has a potential of more than 1500MW of potential capacity. There are more than 11,000 miles (about 17,500km) of canals and aqueducts moving water throughout the State.

To the north, meanwhile, more than 15GW is the estimated attainable capacity of the Canadian kinetic hydro power market, according to An Evaluation of The Kinetic Energy of Canadian Rivers & Estuaries, prepared for the National Research Council of Canada, Hydraulics Laboratory. There are three TISEC projects in Canada in the pre-deployment planning and regulatory stage.

Nova Scotia Power is establishing a tidal demonstration project in the Bay of Fundy with the selection of OpenHydro as the provider of new, in-stream tidal technology. The announcement of funding partners is expected in the spring of 2007. Meanwhile, New Brunswick is in the early stages of planning a pilot plant demonstration project and New Energy’s Canada Canoe Pass Project is progressing through regulatory approvals, expected to be in place by the end of June 2007.

Proprietary generation systems continue to emerge. Ocean Renewable Power Company (ORPC) has completed the initial design of its Ocean Current Generation (OCGen) system and is now in the prototype development phase. The company is aiming to commercialise the technology and begin deployment of tidal current projects within three years.

The company says a simple, rugged, and scalable design of the OCGen module costs less to build, install, and maintain than rival systems. The cross-flow turbine rotates in only one direction regardless of the direction of current flow, so no repositioning is needed in reversing tidal currents.

The turbines and generator rotate on a single shaft that requires no gears, thereby eliminating the leading cause of failure in axial flow turbines. ORPC has filed a provisional patent application covering various design elements and components. The turbine-generator unit is designed to be stackable, so several units can be connected to create a larger power generation module.

A typical project consists of a series of modules connected to an underwater transmission line. The modules will be positioned well below the surface of the water using deep sea mooring systems that minimise impacts to the marine environment and prevent interference with commercial shipping.

ORPC has invested US$950,000 to date, but needs a total of US$8.5M to fully fund the final design, detailed engineering, environmental permitting, procurement, assembly, installation, testing, and monitoring of a prototype module. The prototype module will be assembled on-shore and installed at one or more of the sites in Maine or Alaska for which ORPC has submitted preliminary permits to FERC. ORPC plans to install the prototype module by the spring of 2009 and expects to generate its first commercial revenues in late 2009.

The market for tidal technology is immense and worldwide, since tidal currents flow in all regions of the world, and an estimated 70% of the world population – and electricity load – is within 200 miles (about 320km) of an ocean. Immediate markets for electricity generated from tidal projects are coastal interconnections to existing power grids and off-grid remote coastal and island communities.

According to Roger Bedard, ocean energy leader at the Electric Power Research Institute (EPRI), which has been conducting wave and tidal energy feasibility studies for three years, 40 applications for preliminary permits have been filed by private and public investors for wave and tidal plants totalling over 5GW to FERC. A preliminary permit keeps the holder first in line for developing the site while they are completing the licensing requirements.

The World Renewable Energy Report estimates the cost of wave energy at an average of 9 cents/kWh and tidal and current an average of 8 cents/kWh. Recent EPRI reports have found that, presently, the cost of power from ocean technologies ranges from 7 cents to 16 cents/kWh in a low case scenario. For tidal, the May 2006 EPRI report found that the cost is driven by the resource, a strong resource can yield power at prices as low as 6 cents/kWh. Plus, similarities between tidal and offshore wind bring costs down. And, the costs of offshore wind or wave are stable. Whereas natural gas and oil have fluctuated over the years (with natural gas now higher than ever), offshore wind and wave energy costs are stable, since the cost of renewable power sources like wind or wave are free.


Installation Installation


Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.