Vanderbilt Journal of Transnational Law

First Page



Rapid technological advancement has been the hallmark of post-industrial societies for more than a quarter of a century. This progress is forever disrupting our established legal systems. Nowhere is this tension more evident than in the discoveries of the developing energy industry. An exception to this process is the infant industry of ocean thermal energy conversion (OTEC). The United States Congress recently enacted legislation establishing the legal framework for the OTEC process, which has not yet been proven on a commercial scale.

OTEC is a form of solar energy that takes advantage of the vertical temperature differentials in those regions of the ocean generally between twenty degrees North latitude and twenty degrees South latitude. An OTEC system consists of a power plant, a floating platforms to house the plant, a surface-level seawater system, a deep water seawater system, and a method of transmitting or utilizing the energy produced. Warm surface water is pumped into a heat exchanger to vaporize a working fluid. A turbo-generator converts the resulting vapor's thermal energy into mechanical and then electrical energy. The vapor leaving the turbine flows into a condenser where it is cooled by cold water pumped up from the deep ocean through a long pipe descending as much as 700 meters or deeper.

Although commercial facilities are not expected to be available prior to the late 1980's, two types of OTEC systems are presently under consideration. The closed cycle system6 is closer to commercial realization. In this system, heat derived from surface waters evaporates a working fluid such as ammonia and forces the resulting vapor through a turbine. The turbine powers a generator to create electricity. The vapor returns to liquid form after being chilled with cold water from the ocean depths. The second system is the open cycle system. In this process, warm surface seawater is evaporated in a vacuum. The resulting steam powers a turbine and is then condensed with cold seawater drawn from the ocean depths.

OTEC has the potential to fulfill the energy needs of oil-dependent communities. Because OTEC's energy source is solar, it is renewable. Unlike other solar technologies, however, OTEC can operate twenty-four hours a day, year-round due to the ocean's immense solar-collection properties. Yet OTEC will be used for much more than electrical power generation. It has the potential for ammonia production, which presently requires nearly three percent of the total United States output of natural gas. OTEC can be used to process and refine minerals and produce other energy-intensive products such as aluminum. OTEC power can be used to produce fuel for fuel cells that can be transported and used for electricity elsewhere. Considering all these potential uses, OTEC will be a promising area of renewable energy technology if it evolves in a cost-effective and environmentally acceptable manner.