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http://www.fao.org/docrep/010/ah810e/AH810E00.htm

This paper in effect replaces the excellent, but now long out of print booklet, entitled "Water Lifting Devices for Irrigation", by Aldert Molenaar, published by FAO as long ago as 1956 [1]. Since that time, little more than one generation ago, the human population has almost doubled. In the same short period, over twice as much petroleum, our main source of energy, has been consumed as in the whole of history prior to 1956. But there has also been a much wider awareness of the constraints which must force changes in technology.

The primary purpose of this paper is to provide a basis for comparing and choosing between all present and (near) future options for lifting irrigation water on small and medium sized . land-holdings (generally in the range 0.25 ha to say 25 ha). Small land-holdings in this size range are most numerous in many of the developing countries, and extension of the use of irrigation in this small farming sector could bring huge benefits in increased food production and improved economic well-being. It is also hoped that this paper will be useful to those seeking techniques for lifting water for purposes other than irrigation.