IEGT clearly provides electricity from a renewable resource, in this case water flow, without recourse to burning any type of fuel. Unlike standard hydroelectricity, IEGT does not involve the construction of a large infrastructure, the damming of rivers or streams, or the diversion of any water ways. IEGT can, however, be used in existing water systems controlled by dams or other structures.
Besides the generation of power, IEGT can be used for other water projects. These include desalination, the creation of potable water, and the extraction of hydrogen from water for use in fuel cells.
IEGT is claimed by its proponents to have little or no impact on the environment. The turbine blades rotate slowly enough and are space apart far enough so that migrating fish will not be affected. Environmental groups such as Riverkeeper in New York dispute this, claiming that scientific evidence is not yet available to support the conclusion of no environmental impact.
The East River Project
A company called Verdant Power is testing an IEGT system in the East River, between Manhattan and Roosevelt Island. The first phase, which consisted of a single axial flow rotor turbine, with ten foot diameter rotors, anchored in concrete attached to the river bed. The turbine was not only able to capture the energy from the natural flow of the river, but from tidal currents which can reach 4 knots. The single turbine was able to generate up to 16 kilowatts of power.
As a result of this first phase of the East River Project, Verdant Power is preparing to deploy six single axial flow turbines, with five meter diameter rotors, in the tidal basin of the East River. This system, when installed, will actually generate electricity for the New York power grid. Eventually, Verdant plans to deploy several hundred turbines, generating 5 to 10 megawatts, providing power for New York City.