Tales from the Front Line


Where does the MHK industry stand in North America today and where is it headed? Hydro Review asked two technology developers to discuss the work they have done so far and the potential breakthroughs on the horizon that could push this sector to commercialization.

By Elizabeth Ingram

Elizabeth Ingram is managing editor of Hydro Review.

Energy from the oceans (and rivers, using hydrokinetic devices) could be big business. In fact, 2014 data from the Energy Efficiency & Renewable Energy Wind and Water Power Program at the U.S. Department of Energy quantifies the potential energy resources around the country. Wave energy is quantified at 1,851 TWh/year, river current at 1,381 TWh/year, tidal current at 445 TWh/year, and ocean current at 200 TWh/year.

To help put these numbers into perspective, total electricity net consumption numbers from the U.S. Energy Information Administration reveal that in 2012 3,832 TWh of electricity were consumed. That’s right, there is enough potential in the above-mentioned U.S. waters to fully meet current consumption needs.

The RivGen system is shown here before deployment underwater in the Kvichak River in Alaska

Given this atmosphere, we reached out to a couple of technology developers that are “making waves” in this sector of the hydropower industry, to find out the work that has gone into their technology to date and what they see for the future of MHK in North America.

Wave energy update

— By Reenst Lesemann, chief executive officer, Columbia Power Technologies

Worldwide, a multi-trillion dollar replacement cycle has started for aging and undesirable electricity generation capacity. Much of the replacement will occur with existing resources, but to be ultimately successful, this transition requires the development of clean, new, reliable resources, like wave energy. Columbia Power Technologies’ mission is to make wave power a mainstream renewable, and the core of our effort will be the commercialization of a technology that cost-effectively converts the energy in ocean waves into utility-scale electricity.

The desirable characteristics of wave energy provide a more consistent, reliable and, therefore, easier-to-integrate supply of electricity. We believe this will drive the market forward despite the current dominance, within renewables, of wind and solar. Europe has realized this and is now repeating its traditional early adopter role, fully embracing ocean energy with market-creating accelerators. This includes revenue support, capacity targets and multiple “plug and play,” grid-connected test centers throughout Western Europe.

The latest example of Europe’s role as a global leader in renewables is its dominance in the offshore wind industry. According to the European Wind Energy Association, nearly 1.5 GW of offshore wind capacity was turned on in Europe last year, far outpacing new builds in the rest of the world.

For wave energy, the hostile ocean environment and economic realities of commercial energy projects require a balance of operating and capital costs that, until now, have not been answered by any competitive technology. The difficulty lies in delivering a system that can simultaneously satisfy the competing customer requirements of availability (meaning reliability, operational range and maintainability), affordability and acceptability (customer, stakeholder and environmental).

Our patented wave power system — the StingRAY — has been developed and tested over 10 years, including 13 months of sea trials. We believe it meets these customer requirements. Our approach combines smart design that leverages proven technologies with a capital-efficient product development process, allowing us to rapidly innovate at a low relative cost.

Columbia Power Technologies is a privately-held technology development company formed in 2005, originally licensing a first-generation wave power technology from Oregon State University in Corvallis. Columbia Power’s product development and delivery team, which is also in Corvallis, developed the current, third-generation StingRAY technology.

The StingRAY floats on the water surface and captures and converts the energy from each passing wave into electricity, which is then carried ashore by a grid-connected cable. Like a wind farm, a wave farm will be composed of an array of MW-scale devices, with each StingRAY being kept on station by a simple, but rugged, mooring system.

The StingRAY technology floats on the water surface and captures and converts the energy from each passing wave into electricity.

The StingRAY design is unique in its energy capture and conversion method, capturing energy from the heave and surge forces within each ocean wave and converting it to electricity with a direct-drive permanent magnet generator. This power take-off concept is similar to the dominant approach used in the offshore wind industry. (You can read more about the benefits of direct-drive generators at http://www.gepowerconversion.com www.gepowerconversion.com.) The StingRAY’s primary structural material is corrosion-resistant fiber-reinforced plastic (fiberglass), long recognized as cost-effective and reliable in the marine environment.

Having completed tens of thousands of hours of modeling and prototype testing, we are moving through our remaining pre-commercial milestones: validation of our final major sub-system; independent verification of the StingRAY design; and completion of pre-planning for the StingRAY open ocean test. The StingRAY will be commissioned and deployed at the U.S. Navy’s grid-connected, deep water Wave Energy Test Site in 2016, leading to commercialization and market entry in 2017.

The United Kingdom’s Low Carbon Innovation Co-ordination Group estimates that 188 GW of wave energy capacity could be installed over the next 35 years. This represents an investment of nearly $50 billion and capacity to light nearly 150 million homes. Columbia Power looks forward to making this a reality.

Tidal energy update

— By Christopher Sauer, president and chief executive officer, Ocean Renewable Power Company

Development of Ocean Renewable Power Co.’s tidal energy power system, called TidGen®, is advancing very well. In 2012, we were the first ocean energy project of any kind to deliver electricity to the U.S. grid. This work demonstrated that the tidal application of our technology works. At the same time, it was too expensive and wasn’t as reliable as it should be.

So, with funding from the U.S. Department of Energy, we are working on version 2.0 of our TidGen Power System. We are significantly increasing extraction efficiency and reliability and dramatically reducing costs. We are at a point in the program where we can identify the magnitude of the cost savings.

When this work is complete by the end of 2015, version 2.0 of both TidGen and our river adaptation of this technology, called RivGen®, will be competitive with diesel (used by remote “islanded” communities to generate electricity on micro-grids).

We are focusing on this market because this is where our RivGen and TidGen systems are competitive with existing, but far too costly and polluting, diesel systems. Remote villages in Canada, Alaska and elsewhere outside the U.S. are great markets for this technology. These communities rely on expensive diesel generation, and both the TidGen and RivGen systems can reduce their costs and carbon footprint.

For example, the entire electricity needs of the village of Igiugig on the Kvichak River in Alaska can be supplied using two 25-kW RivGen devices. And at False Pass in the Aleutian chain in Alaska, they pay more than $0.50/kWh using diesel (the average American pays $0.12/kWh), and we hope to install two or three of our TidGen devices there.

In addition, these markets will help get our company to scale in terms of production value of our technology. Serving those markets will help reduce our costs even more, and six to eight years from now, I can see ORPC building projects and being able to compete with any other electricity source on the grid.

Our TidGen technology started as an idea of Captain Paul Wells, one of the company’s co-founders, who wanted to generate electricity from the Florida Current. Originally Wells, John Cooper and I got together and thought we would be able to buy tidal energy equipment. We quickly discovered there wasn’t any such equipment.

We went into the technology development process totally impartial to any particular kind of design. We had two basic questions: What is the best way to take moving water and convert it into mechanical energy? How can we take the mechanical energy produced and bring it to shore?

We did a study with the U.S. Navy in early 2006 through its Carderock Division and came up with the design concept of the TidGen system. It uses cross flow turbines and an underwater permanent magnet generator. The Navy thought this would be the most survivable and rugged design. However, the state of knowledge on cross flow turbines was much less advanced than that on propeller technology.

To date we have gone through four generations of our technology, first a turbine prototype tested in 2007, then a prototype test in 2008, a beta version in 2010 that produced grid-compatible power while deployed from a barge, and finally a 150-kW unit installed in Cobscook Bay, Maine, in 2012, which sent power to the Emera Maine grid. So version 2.0 of our TidGen system is actually our fifth generation, and it will have a capacity of up to 600 kW.

Total committed capital for this work has been $63.5 million, almost half of which has come from federal and state grants, loans and other programs and a little more than half of which has come from the private sector.

We are working on raising an additional $10 million and with this we think we can achieve break-even on a cash flow basis and start to become profitable within three years.

We do have a 20-year power purchase agreement for a 5-MW project in Maine at above market pricing. We will build the first of the version 2.0 technology next year, test it in Cobscook Bay and benchmark its performance. If we hit our targets, we will start building the Maine Tidal Energy project in 2017. We will likely co-own this project with a partner, and we expect it to cost about $40 million all in.

Current energy update

Several companies are doing work in this arena, including Aquantis. The Aquantis Current Plane, or C-Plane, is designed to harness energy from marine currents around the world, such as the Gulf Stream. This technology has been developed through the help of an award from the U.S. Department of Energy announced in 2009, intended to validate analytical design tools and develop the direct drive component.

In-water testing of current technologies may soon be possible thanks to plans in the works to install the world’s first offshore test berth for small-scale ocean current turbines at Florida Atlantic University’s Southeast National Marine Renewable Energy Center. FAU and the U.S. Department of Interior’s Bureau of Ocean Energy Management signed a five-year lease agreement in June 2014.

The lease allows installation of multiple anchored floating test berths on the U.S. outer continental shelf 13 miles offshore from Broward County, Fla. Each test berth will consist of a buoy anchored to the sea floor and will allow ocean current turbine prototypes up to 100 kW in capacity to be deployed from vessels moored in the Gulf Stream for a few weeks at a time.

Work to develop this site is being supported by funding of nearly $20 million from the DOE, the state of Florida and private companies.


Learn about MHK in person

We are pleased that the Ocean Renewable Energy Conference X, organized by the Oregon Wave Energy Trust, is being co-located with HydroVision International next month in Portland, Ore.

This is a great opportunity to attend seven informative panel presentation sessions covering the gamut of the marine and hydrokinetic energy industry worldwide, including a plenary session entitled: “What’s the Vision? Where’s the Progress?”

Other sessions cover technology development, the role of test centers, niche markets to boost development, emerging market concerns and environmental issues. The final session of this three-day conference provides perspectives on challenges surrounding MHK from representatives of federal, state and local government bodies.

For a complete list of the seven sessions and our outstanding lineup of speakers, visit http://bit.ly/1EkqTQ6. And when you’re ready, you can click on the Register button on the top right to sign up!

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