Reducing energy use and

costs in irrigation systems.

José Mª Tarjuelo

Miguel A. MorenoBarcelona, April 2017

Technologies to apply• Tools and models for saving water, optimizing

economic water productivity and minimizing environmental impact (crop models, ICT, remote sensing,

models and tools for DSS…).

• Tools and models for improving irrigation infrastructure design and management as a whole (from water source to

the emitter), based on water and energy savings

• Actions to reduce energy consumption and/or cost (benchmarking, energy audits, renewable energy…)

• Crosscutting activities: – a) Irrigation Advisory Services

– b) Web-GIS platforms to transfer information and technology

– c) Network of leaders (farmers and technicians)

Castilla-La Mancha

Examples in Spain and Castilla-La Mancha

Spain: 3,8 Mha irrigated (19% cultivated land) (3,5 actual) . Contributes 65% of NAP(> 13,000 M€). Consume 80% of the water (68% used)

Productivity compared with rainfed: 6 times (4 times + income)

OVERVIEW OF ACTIONS TO MAKE IN PRESURIZED IRRIGATED AREAS

ANALYSIS AND EVALUATION

Energy auditsBenchmarking

MANAGEMENTOPERATION

FACILITIESIRRIGATION NETWORKSPUMPLING

IRRIGATION

IN PLOT

Sprinkler or

drip irrigation

DESIGN

Optimized rotation

schedule or

on-demand ??

•Layout

•Gated flow rate

•Q in lines

•Economic sizing

•Analysis

Energy rates

Models

ModelsModels

Renewable energy

Phase 2

Phase 1

Phase 3

IAS, ICT, DSS

Semi-Arid region

Overexploitation of aquifers

493 300 ha irrigated

4% Surface irrigation

22% permanent sprinkler irrigation

18% Centre pivot systems

56 % Drip irrigation

Castilla La Mancha AGROECOSYSTEM

Main Crops: cereals (barley,

wheat and maize),

vegetables (onion, garlic …) vineyard, olive tree, almond

80% Groundwater

Water scarcity

Expensive Energy

Precipitation

Evapotranspiration

GROUNDWATER

EXTRACTION.

Irrigation Water

Requirements …

Storage

Change

Percolation

RechargeWater

Quality

run-off

River-aquifer

interactionCrop classification

Water scarcityExpensive Energy

Overexploitation of aquifers

CRITICAL PROBLEMS AND CONSTRAINS

• Low water availability for irrigation due to:

– high frequency of drought periods

– environmental constraints

– increased needs in priority uses.

• Overexploitation of groundwater resources.

• Risk of groundwater pollution (nitrates)

• High water price due to energy costs

• Limited economic water productivity at farm level

• Insufficient information and transfer to final users

about the use of existing technology for efficient

water and energy management

SOLUTIONS

• Increase irrigation water productivity using DSS tools, models, and devices for improvement of facilities design and water and energy management

• Which DSS tools and models?

Some actions

1. Use of Irrigation Advisory Services (IAS)

2. Design and management of irrigation systems

3. Analysis of water and energy use (energy audit

and Benchmarking)

4. Optimal cropping pattern determination

5. GIS tools for irrigated areas management

6. High and very-high resolution remote sensing

• Helping farmers to make efficient use of resources for production (water, energy, fertilizers, etc.)

• Advise on design and management of irrigation systems (technologies, crops,...)

• Diffusion of water requirements for the main crops and bases for irrigations scheduling. (Network of weather stations )

• Training of farmers. Help for decisions making (workingtogether with farmers)

• Transfer tools for water saving and proper cropping pattern selection at farm level (remote sensing, at different resolutions, for crop status determination together with DSS models and tools).

• Use Benchmarking techniques to evaluate the performance of irrigated areas

• Use the existing Web-GIS platform to perform information and technology transfer to final users in a feed-back process

1. Irrigation Advisory Service (IAS)

2. Design and management

of irrigation systems

www.arentio.com crea.uclm.es

TOOLS (developed in MATLABTM ) to aid in design and management of irrigated areas

A) For pressurized irrigation system design

– Design of sprinkler and drip irrigations sub-plots (PRESUD)

– Design of pressurized irrigation systems with minimum water application cost (from the water source to the emitter)

(DOPIR) and for center pivot (DOP and DEPIRE)

B) For pumping design

– Optimal borehole design (DOS),

– Optimal pumping stations design (DOEB).

C) For pumping stations analysis :

– Analysis of borehole (AS),

– Analysis of energy efficiency in pumping stations (MAEEB)

– Analysis of irrigation network (MAWE)

Web: crea.uclm.es

A) Tools for design of irrigation systems in plot

Autocad

QGIS

PRESUD tool for design of sub-plot with sprinkler and drip irrigation systems with minimum water application cost (investment + operation) (Carrion et al. 2013 and 2014); (Moreno et al. 2012 )

Discharge distribution in subunit

PRESUD

Optimal design of centre

pivot (DOP)

B1. Tools for pumping design

Determine the optimal shape of

the characteristics curves of the

pump and the pumping and

distribution pipes diameters to

minimize the total cost

(investment + operation) taking

into account the energy rate in

the different periods

Optimal design of boreholes (DOS) (Moreno et al 2010)

Optimal design of pumping stations (DOPEB)

• To determine the minimum total cost of the

pumping station (collective or individual

irrigation networks) through the optimization

of the shape of characteristic and efficiency

curves of the pumps and the number of

pumps and variable speed drivers to be used in the regulation.

B2. Tools for pumping design

C) Tools for analysis to improve energy efficiency

• 1. AS (Analysis of boreholes). Calculates the actual

pump efficiency from hydraulic and electrical measured

and simulate possible management improvement .(Moreno et al 2010)

• 2. MAEEB (Model for Analysis of Energy Efficiency in

pumping stations). Simulates the behavior of the pumping

stations and proposes the more energy efficient

regulation options, besides determining the optimum

regulation pressure head to minimize the energy cost of

pumping station. (Moreno et al 2007)

• 3. MAWE (Model of Analysis of Water and Energy)

Water and energy analysis in collective irrigation network

EXAMPLE OF BOREHOLES ANALYSIS (AS)

The Chozilla example

C1. ANALYSIS OF BOREHOLES (AS)

• Main problems observed:

• Significant increase of water lift.

• Leakage (breakage) of the impulsion pipe.

• Wear of impellers.

• Main proposals to improve:

• Replacing the pump.

• Replacing part of the impulsion pipe.

• Repair or modification of impellers.

C2. ANALYSIS OF PUMPING STATIONS

(MAEEB)

Parallel pump coupling for

maximum efficiency

Web-GIS platform, named MAWE, to perform an adequate management of large-scale irrigation networks, optimizing water and energy.

C3. ANAYISIS OF COLLECTIVE IRRIGATION NETWORKS

ENERGY AUDIT

Development of tools and measures

to improve the design and management of irrigation facilities

ENERGY AUDITSEnergy audit purpose :

1) Assessment of energy consumption

2) Propose and implement measures for energy

and cost savings, economically viable.

To do so is necessary to analyse:

a) The irrigation facilities

b) The management and organization of water

distribution

c) Have tools to propose improvement measures

and to adjust energy consumed to the energy

rate periods under contract.

ENERGY AUDITSA. Measures that produce energy and cost savings :

1. Improving equipment that consume energy

2. Improving facility design

3. Improving facility management

B. Measures that produce cost savings :

– Studying the energy rate periods adjusted to the required power and real consumption.

– Contracting only the power actually used during each period.

– Adjusting the facilities operation to the energy rate periods under contract.

CONCLUSIONS• The energy efficiency of WUA audited is high,

although it can be improved.

• The energy audits in WUA have detected operational problems, mainly in boreholes and pumping stations, and the need to improve the energy contract with the electricity company.

• The tools and methodologies developed permit the detection and analysis of problems and help in decision making for the proposed improvements.