Small hydro and the environmental implications of its extensive utilization

There is a great resurgence of interest all over the world in the development of 'small' hydropower systems (SHS). The surge is essentially propelled by the belief that SHS, which include mini, micro, and picahydel systems, are a source of clean energy with little or no adverse impacts on the environment. This paper presents an overview of SHS and then examines in detail whether the prevalent belief in the great environment-friendliness of SHS is really justified. It is brought out that widespread use of SHS is likely to cause, per kilowatt of power generated, no less significantly adverse environmental impacts than large hydropower systems and some other conventional sources of energy. While supporting the ongoing global efforts to maximize the use of SHS, the authors advocate much greater circumspection than is being exercised at present vis-a-vis SHS. The authors believe that if the likely pitfalls are foreseen before SHS are put to widespread use, and remedial measures taken accordingly, it may save the world from considerable disillusionment and environmental damage. (C) 2010 Elsevier Ltd. All rights reserved.