Since the first rudimentary agriculture started with man cultivating plants near his dwelling, he has had to carry water to keep his crops alive. He developed simple systems to raise water, like the shadoof, and later more sophisticated systems, such as norias, Persian wheels and qanats. The power to move such devices came from man himself, animals or the force of gravity. Over the years man learned to harness other sources of energy.
This publication has been prepared to help planners and engineers consider the potential and application of alternative sources of energy for prime movers. Research and field application are continuous in many parts of the world, but the degree of success varies. As new information becomes available, systems developed over recent decades, and even long before that, may be modified or refined to take advantage of new ideas and modern technology. It is an old subject, but innovations continue.
Consequently, this publication cannot be regarded as a comprehensive treatise on the subject of alternatives for water lifting devices, nor can it be considered as the final state of the art. It does, however, seek to provide enough technical background on promising systems for possible application in the field, and as a base for further evolution.
This first edition has been prepared with a view to eliciting expert comment and further contributions which would be considered for incorporation into and updated and possibly more comprehensive publication. It is hoped that the document will serve as a practical reference for the guidance not only of experts and counterparts in the field, but also for government officers and others concerned with the planning, design and operation of projects using these techniques in FAO's member countries.
Comments and suggestions for improvement of this Irrigation and Drainage Paper will be welcome and should be addressed to:
Chief
Water Resources, Development and
Management Service
Land and Water Development Division
Food and Agriculture Organization
of the United Nations
Via delle Terme di Caracalla
00100 Rome, Italy