Makai Lockheed Concept OTEC Pilot Plant.JPG [3]

The Ocean Energy Council [4] recently honored Dr.Ted Johnson, the director of Lockheed Martin's (NYSE: LMT [5]) ocean thermal energy conversion (OTEC) program, with its Ocean Energy Pioneer award for his support and contribution to OTEC technology.

OTEC leverages the ocean's natural thermal ingredients to produce a significant amount of constant, renewable power. Lockheed has been involved in OTEC research since the 1970s [6], when it developed a pilot plant but the project was later abandoned when the Reagan administration withdrew funding.

In geographical areas with warm surface water and cold deep water, the temperature difference can be leveraged to drive a steam cycle that turns a turbine and produces power, which can be directly connected to a power grid.

In an OTEC system, warm surface sea water passes through a heat exchanger, vaporizing a low boiling point working fluid to drive a turbine generator, producing electricity.  The vapor is condensed back to liquid after passing through a second heat exchanger that connects with large amounts of cold ocean water pumped from deep below the surface.  There is no supplemental storage of the power required and practically zero carbon emissions.

OTEC technology could support states like Hawaii and other islands which rely on imported power in switching to renewable enrgy, drawing on their proximity to warm tropical waters, a key requirement for the technology. Aside from Hawaii, the Navy is aso interested in OTEC to power its remote island bases. [7]

EnergyBoom asked Dr.Johnson about the challenges in commercializing this technology and the head way that Lockheed has made in this field.

1.      Historically, the challenge with OTEC has been to produce large-scale power. How much progress has been made since the 70s? Do you expect it to become economically viable in the near future?

Critical advances in the technologies related to an OTEC system will allow OTEC to serve as an economically-viable energy source.

Examples include new composite materials and construction techniques to address some of the higher-cost components of an OTEC system, such as the cold water pipe and heat exchangers.

The potential for OTEC to support a range of global energy and water-supply requirements is within reach.  Lockheed Martin and its partners are working on the design for a small commercial-sized OTEC plant.  A “pilot” plant, which would be built first and could be customized to provide the engineering and operations team all of the additional insight and access required to monitor and understand the plant’s operations.  Based on the lessons learned from that incremental step, the team will make commercial utility-scaled plants a reality.

The efficiency of an OTEC will vary by the size of the plant. The larger the plant, the greater the efficiency. The efficiency of OTEC plants is relatively low when compared to other energy sources, but it’s important to note that unlike other energy sources, OTEC is a completely renewable source of energy without any pollution. 

3.      Tell us about the DOE contract. How close is Lockheed to making OTEC technology commercial? To which locations will this potentially expand OTEC utilization?

In 2008, Lockheed Martin was awarded a cooperative agreement contract by the U.S. Department of Energy [9] to demonstrate innovative technologies to enable ocean thermal energy power generation. Under the terms of the cooperative agreement, Lockheed Martin will demonstrate a cold water pipe fabrication approach using modern fiberglass technology and recent low-cost composite material manufacturing methods at prototype and pilot plant scales.

The cold water pipe is one of the most challenging components of an OTEC system. OTEC uses the ocean’s thermal gradient to drive a heat engine. Since the ocean’s temperature difference is relatively small, large volumes of seawater must be moved to generate commercial levels of power. The fabrication and installation of large diameter cold water piping -- required to reach depths of thousands of feet -- represents one of the significant technical challenges to the successful installation and operation of an offshore OTEC system.

Renewable and reliable alternative energy is a critical need as the world’s oil supplies are depleted. The goal of Lockheed Martin’s work with OTEC is to address the key concerns of energy security, global warming, depletion of non-renewable fossil resources and pollution. Though this energy source is particularly relevant to the state of Hawaii, we hope to see ocean thermal energy play a major role in solving the global energy crisis.  More specifically, as a baseload power source, OTEC is an ideal renewable energy option for many military bases in their quest to increase their energy independence.

The team is engaged in a variety of activities aimed at the design of a modern era OTEC power plant. For example, the team is working closely with Makai Ocean Engineering [10]on a test program for OTEC heat exchangers, one of the challenging technical components of an OTEC system.

        The waters in and around the state of Hawaii provide an excellent place to build and test a pilot plant due to the proximity to ocean thermal resources. Lockheed Martin hopes to move forward and have pilot plant in the water by the 2012-2013 time frame. Hawaii has signed an agreement with the Department of Energy called the Hawaii Clean Energy Initiative [11]. This initiative “seeks to transform Hawaii’s energy portfolio into a predominately renewable energy mix, moving away from reliance on fossil fuels.”  Additionally, several of Hawaii’s Department of Defense bases are seeking to increase the renewable energy content of their base requirements.

Image courtesy of Makai Ocean Engineering.