Fluidos

ARTICLE IN PRESS
BIOSYSTEMS ENGINEERING

98 (2007) 479– 486

Available at www.sciencedirect.com

journal homepage: www.elsevier.com/locate/issn/15375110

Research Paper: SW—Soil and Water

Measurement and improvement of the energy efficiency at
pumping stations
´
´
´
Miguel A. MorenoÃ, Pedro A. Carrion, Patricio Planells, Jose F. Ortega, Jose M. Tarjuelo
Centro Regional deEstudios del Agua, Castilla-La Mancha University, 02071 Albacete, Spain

article info

Rational and efficient use of energy is essential for sustainable development. In Spain, as in
many other countries, electrical energy is the main source of energy in irrigation; therefore,

Article history:

research with the aim of increasing the efficient use of electrical energy should be

Received 11April 2007

arranged.

Received in revised form

The goal of the research performed was to develop a model for analysing energy

11 September 2007

efficiency at pumping stations, which permitted the determination of the sequence of

Accepted 11 September 2007

pump activation that minimised the energy cost for real demand scenarios. The model was

Available online 7 November 2007calibrated for the pumping station of Tarazona de La Mancha (Spain) by measuring
hydraulic and electrical parameters for each pump.
One of the main aspects to consider when carrying out the energy cost analysis at
pumping stations is to estimate the discharge distribution throughout the irrigation
season. The optimum sequence of activation of pumps was the option that best fitted the
dischargedistribution in terms of efficiency.
This paper illustrates that simple electrical and hydraulic measurements at pumping
stations can help to improve their management. In the case study, a cost saving of 16% was
obtained by changing the regulation of the pumping station. In only one season, the
additional costs of applying this methodology (electrical network analysers, flowmeters,
and pressuretransducers) would have been recovered with the energy efficiency
improvement. Results could vary in other cases depending on the discharge distribution
and the working points of the pumps.
& 2007 IAgrE. Published by Elsevier Ltd. All rights reserved.

1.

Introduction

Rational and efficient use of energy is essential for sustainable development. In Spain, as in many other countries,agriculture requires high energy consumption, mainly for
machinery and irrigation. This consumption is increasing due
to the irrigation energy requirements when using pressurised
irrigation systems (sprinkler and drip irrigations). These
systems permit easy management and automation, and a
proper adjustment to cropping pattern changes, depending

on crop market trends. Research with theobjective of
increasing the efficient use of electrical energy in irrigation
should be developed.
Some research has been carried out to optimise the total
cost (investment and energy costs) in pumping stations
(Moradi-Jalal et al., 2003, 2004; Pulido-Calvo et al., 2003a;
Planells et al. 2005). They attempted to obtain the combination
of variable and fixed-speed pumps that best minimised costs.These studies considered the theoretical characteristic curves
of the pumps, which means only considering the pump and

ÃCorresponding author.

E-mail address: MiguelAngel.Moreno@uclm.es (M.A. Moreno).
1537-5110/$ - see front matter & 2007 IAgrE. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.biosystemseng.2007.09.005

ARTICLE IN PRESS
BIOSYSTEMS ENGINEERING

98 (2007) 479– 486

Nomenclature

NQi

Ci
Cj
fi

PLC
Q
tij

H
HU
i
j
k
Nabs
n

average energy cost for the discharge interval I, h
energy cost in the tariff period j, h
frequency of every discharge i in the irrigation
season
pressure head, m
hydrogeologic unit
discharge increment
tariff period
calibration coefficient, %
measured absorbed power, kW
number of flow values for...