New Hydro

Editor’s Note: HRW is pleased to introduce this new department. In each issue, look to “New Hydro” for information about innovative and emerging water-based power generation, such as wave, tidal, wind with hydropower, and hydrogen produced from hydro.

In-stream projects slated for Zambia, Colombia

In Zambia and Colombia, UEK Corporation is preparing for installation of in-stream (kinetic) turbines directly in rivers, without a dam or other impoundment. These turbines, called underwater electric kites, are anchored to the bottom of the river by a cable. Controlled by a computer, the turbines ascend or descend until they locate the layer of water with the fastest current.

The pilot project in Zambia consists of two identical 8-foot-diameter turbines, each with a capacity of 50 kw, in the Zambezi River. This project, intended to provide electricity for a missionary school and hospital, should be in place by late summer 2007.

A similar project in Colombia consists of two identical 10-foot-diameter turbines with a total capacity of 90 kw on the Caqueta River. Electricity produced will supply two local communities. Funding is in place, but details for timing of the installation must be worked out with the local government.

The underwater electric kite can be installed anywhere flow velocity is more than 2 meters per second. Minimum depth of water for placement of the turbine is 120 percent of the diameter of the unit.

IEA annex studies integration of hydropower and wind

The International Energy Agency’s (IEA) Annex XXIV Integration of Wind and Hydropower Systems is in the third of four years of studies related to integrating generation from wind and hydroelectric projects. Participants in the annex represent seven countries: Australia, Canada, Finland, Norway, Sweden, Switzerland, and the United States.

Research is proceeding in four areas. First, case studies are under way to investigate the grid integration of wind energy, particularly on grids with hydropower resources.

Second, several countries are contributing case studies related to how integrating wind and hydro may necessitate changes in the way hydropower facilities operate. These studies will investigate effects to operation, maintenance, revenue, water storage, and the ability of the hydro facility to meet its primary purposes.

The third area of case studies is on the economic feasibility of integration. These studies aim to identify which market types are practical for wind-hydro integration, as well as the key factors driving the economics of integration.

Finally, several countries will contribute simplified models of wind-hydro integration. The goal is to develop a technique to approximate the potential for integrating wind and hydropower.

All annex work is expected to be completed by May 2008. Once the studies are complete, the annex will create an online database available to participants and a summary report that will be widely available.

The annex is self-funded by the participants. The National Renewable Energy Laboratory in the United States is the operating agent in charge of managing the annex.

– For more information, see www. or contact Thomas L. Acker, PhD, Northern Arizona University, (1) 928-523-8363; E-mail: tom_acker@

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