Feasibility Study on Solar Irrigation Pump Project for REB by ADB

Bangladesh: Solar Irrigation Feasibility

Asian Development Bank

Bangladesh: Solar PV Pumps for Agricultural Irrigation (under Loan 2769, Part B (iv).

Feasibility Study

DRAFT FINAL REPORT

Prepared under Asian Development Bank Loan 2769, Part B (iv): Power System Efficiency Improvement Project

October 2015

1


Table of Contents

Executive Summary Page # 51.1 Introduction Page # 7

1.2 Appointment Page # 71.2.1 Objective and Scope Page # 71.2.3 Detailed Tasks and/or Expected Output Page # 91.3 Approach Page # 102 Agricultural Irrigation in Bangladesh Page # 112.1 Crops and Extent of Irrigation Page # 112.2 Irrigation Practices Page # 123 Solar Powered Water Pumping Page # 153.1 Technological Evolution Page # 153.2 Global Status Page # 153.3 Application in South Asia and Bangladesh Page # 173.3.1 Previous Initiatives Page # 173.3.1 Current Initiatives Page # 214 Agriculture and Irrigation in Bangladesh Page # 214.1 Basic Structure of Crop Irrigation in Bangladesh Page # 214.1.1 Crops and Cropping Patterns Page # 214.1.2 Basic Water Requirements Page # 214.1.3 Water use: Page # 224.1.4 Identification of Underground Salinity Front of Bangladesh Page # 234.1.5 Irrigation Intensity Page # 234.1.6 Irrigation Cycles Page # 234.1.7 Modelled Water Demand Page # 244.1.8 Energy Sources for Bangladesh Page # 254.2.1 Grid-Connected Pumps Page # 254.2.2 Diesel based Irrigation Pumps: Page # 255 Issues with Current Irrigation Solutions Page # 265.1 Tariff Subsidies Page # 275.2 Water Resources Page # 285.2.1 Water Resources in Bangladesh Page # 285.2.2 Changes in Irrigation Patterns and Water Table Impacts Page # 296 Technical Analysis Solar PV Water Pumps in Bangladesh. Page # 306.1 Present Status of Solar Energy Utilisation Page # 306.2 Solar Energy Resources in Bangladesh: Page # 306.2.1 Estimation of Resource Availability Page # 316.2.2 Estimation of Array Output Page # 326.3 Solutions for Solar PV Water Pumping in Bangladesh Page # 337 Water Pumping Energy Model Page # 347.1.1 Estimation of Hydraulic Duty Page # 347.1.2 Selection of Design Month Page # 347.2 Problems with Solar Irrigation Pumps and counter measures: Page # 347.3 Technology Choices Page # 347.4 Types of Pumps Page # 347.5 Types of Motors Page # 347.5.1 Water Distribution Page # 357.5.2 Solar Energy Conversion Equipment Page # 357.6 SCOPE of Solar Water Pump against Diesel Pumps: Page # 357.7 Area Selection for solar Pump installation: Page # 378 Conclusion Page # 42

2


Tables

Table 1: Organization Wise Summary of Irrigation Equipment Used, Area Irrigatated (2013-14) Page # 12

Table 2: Comparison of Solar PV Pumping Solutions Page # 16

Table 3: Water Demand for Mixed Crops in Dry Season (Ltr/Bigha/day) Page # 22

Table 4: Area Irrigated by Different Methods, 2007-08 to 2010-12 (Thousand acres) Page # 22

Table 5: Modelled Irrigation Water Requirements in Bangladesh Page # 24

Table 6: Monthly Energy Generation Mix Page # 27

Table 7: Electricity Tariff structure in Bangladesh Page # 27

Table 8: Agricultural Subsidy during the Five Fiscal Years (in Crore Taka) Page # 28

Table 09: Monthly Global Solar Insolation at Different Cities of Bangladesh (in kWh/m2/day) Page # 31

Table 10: Long Spells of Overcast Days Page # 31

Table 11: Estimated Monthly Solar PV Electricity Output in BANGLADESH (kWh/kWp per day) Page # 32

Table 12: PBS Locations in Bangladesh covering 5000 solar Irrigation pumps Page # 38

Table 13: Comparison between Diesel and Solar Irrigation Pump Page # 40

Figures

Figure 1: Typical Solar Powered Irrigation Pump Page # 15

Figure 2: Solar Irrigation Pumps locations in Bangladesh Page # 20

Figure 3: Cropping Pattern Page # 21

Figure 4: Water Use Page # 22

Figure 5: Underground salinity front at a depth of 33.84 m (110) Page # 23

Figure 6: Annual Solar Insolation Map of Bangladesh Page # 30

Figure 7: Availability of Solar Resources in Bangladesh Page # 32

Figure 8: Three Cropped land Areas in Bangladesh Page # 37

3


CURRENCY EQUIVALENTS(As of 13 Oct 2015)

Currency unit – Bangladesh Taka (BDT)$1.00 = BDT 78.00

ABBREVIATIONS AND ACRONYMS

ACADBAEZBEEBEPCGWBDCDHIDNIDSMGHIGoBGovGWhhaha-mhpkWkWpkWhMPPTmMJmmMWMWhIDCOLPVREBREBTATWhVFVSDWp

------------------------------------

Alternating CurrentAsian Development BankAgro-Ecological ZoneBureau Of Energy EfficiencyBest Operating PointCentral Ground Water BoardDirect CurrentDirect Horizontal IrradianceDirect Normal IrradianceDemand-Side ManagementGlobal Horizontal IrradianceGovernment Of BangladeshGovernment Gigawatt-HourHectareHectare-MeterHorsepowerKilowattPeak KilowattKilowatt-HourMaximum Power Point TrackingMeterMegajouleMillimeterMegawattMegawatt-HourInfrastructure Development Company Ltd.Photovoltaic And Present ValueRenewable EnergyBangladesh Rural Electrification BoardTechnical AssistanceTerawatt-Hour (1,000 Gwh)Variable FrequencyVariable Speed DrivePeak Watt

NOTES

(i) The financial year in Bangladesh is 1 July – 30 June. Unless otherwise stated, all years refer to financial years.

(ii) In this report, BDT refers to the Bangladesh Taka and “$” refers to the US dollar.

4


Executive Summary

Starting paragraph for Asian Development Bank, We are introducing the Solar Irrigation Pump project under the implementing agency Rural Electrification Board (REB). In late October 2015, the Asian Development Bank (ADB) engaged consultant firm RACE Tech, to undertake a broad ranging study of the feasibility of replacing existing grid-connected and diesel-powered irrigation water pumps with solar powered pumps in the Bangladesh under the scheme of Palli Bidyut Samity (PBS) is the Bengali name of a Rural Electric Society.

It started in 60s for crop intensification to increase crop production. Water was and still is the main commodity in this intensification. The two main forms of intensification are irrigation and flood control (and drainage without or with irrigation - FCD and FCDI respectively). At that time Aman (Monsoon rice) and Boro (Summer rice) was the principle crops. This is pre Bangladesh period. DND (Dhaka – Narayangonj – Demra) project was one of such project. In the late 1960s Low Lift Pumps (LLP) had been rapidly deployed under rental arrangements by the East Pakistan Agricultural Development Corporation (EPADC). Deep Tube Wells (DTW) were also promoted under rental arrangements by EPADC (and subsequently by the Bangladesh Agricultural Development Corporation - BADC), but spread more slowly from the late 1960s to the present. This DTW (Deep Tube Well) is still promoted by BADC.

In the post-independence era, privately owned Shallow Tube Wells (STW) spread rapidly irrigating HYV Boro rice from groundwater, sponsored initially by the BADC, but then through credit schemes of the nationalised banks.

In the initial stage, Diesel engine was the basic prime mover for the pumps. Engines were rated between 5 to 12 HP. At that time electricity distribution was not that wide spread. During 80s electricity distribution was made to rural level with the formation of REB (Rural Electrification Board) in 1977.

With this formation of REB, electric motor driven STW (Shallow Tube Wells) become very popular as electric motor as prime mover is less cumbersome to maintain, run and operate. But this popularity put enormous burden on electric generation. During the first decade of 2000, this burden was so severe that during summer season, load shedding (Planned outage) was applied everywhere and farmers become annoyed. Slowly they turned to diesel engine as prime mover for the pumps. It is to be mentioned here that both the electricity and diesel were subsidised at farmer level.

However, introduction of solar power driven irrigation pumps has been influencing the agricultural sector enormously since last decade worldwide. Farmers in off grid areas find a positive alternative solution to the diesel based irrigation pump with Solar Powered irrigation pumps.

As with the objective this paper upholds the project feasibility study for Solar Driven Irrigation pumps against diesel powered pumps along with various comparisons matrix and investment patterns to make the project successful. The study finds that Solar Water pumps may be more effective solutions for irrigation for vegetables and mixed crops rather than confining those only for paddy cultivation. As such in the study areas for pump installations are indicated primarily, however, an extensive study is required to find exact locations for solar pump installation.

However, the study further finds that recently 2.5 hp diesel pumps getting popular among the end users due to its low cost, less weight and easy carry facilities for stocking when irrigation season is over for a while or even for maintenance issues. Therefore, in contrast 1.5 Hp

5


solar water pumps has been proposed instead of 2.5 Hp diesel pumps, 1.5 Hp Solar Pumps are of low cost, durable, more output and affordable for the target farmers.

Based on Technical and Financial aspects, other solar irrigation pumps of upper capacities are also taken in consideration in comparison to existing Deep Tube Wells (DTW) and Shallow Tube Wells (STW) to find their feasibility against diesel pumps.

As per market survey, due to sharp declines in price of solar PV panels in recent years, “funding gap” can be minimised so that stakeholders could afford to pay for solar pumping to make it financially viable against existing diesel based solutions, and farmers will be ready to pay for delivered waters from the pump with comfortable affordability.

In addition, possible increase in temperature due to climate change will bring a radical change in the management of both surface and ground water resources. It is said that South Asia might experience a 30 percent drop in agricultural production by 2050. And if water becomes limiting the situation will aggravate further. As rice is dominating in the cropping pattern of Bangladesh significant increase in irrigation water use efficiency will lead to substantial saving of the precious resource which could be used for other crops, livestock and human domestic consumption. Appropriate water management practices, efficient irrigation techniques and low water consuming cropping patterns are needed for sustainable agricultural productivity in Bangladesh.

.

6


1. Introduction

1.1 AppointmentThe Asian Development Bank (ADB) engaged consultant firm RACE Tech and to undertake a broad ranging study of the feasibility of replacing existing grid-connected and diesel-powered irrigation water pumps in the rural areas of Bangladesh with solar-powered pumps.

Work commenced on the assignment in October 2015 with a first field mission to REB.

1.2 Objective and ScopeThe specific focus is to assist the ADB’s project officer to prepare a techno-financial presentation (technical materials) to show the overall scope of project construction and investment program for the solar PV pumping systems for agricultural irrigation across rural areas of Bangladesh.

1.2.1 Detailed Tasks and/or Expected Output

The techno- financial presentation will include PV systems (electro-mechanical equipment; power electronics), and needed civil and earth works aspects as follows:

Technical aspects

Key electrical parameters Sizing of solar generator Sizing balance of system; wiring and cabling. Sizing electrical pump Definition of supporting structures Power Electronics and telecommunication for fault announcement

PV Module :i) IEC 61215 and IEC 61730 certified by TUV

ii) Specifications: PV Data

1 Model No : To be mentioned

2 Name and Origin of Cell manufacturer : -DO- 3 Peak Power Pmax [Wp] : -DO- 4 Tolerance [%] : -DO- 5 Max. Power Current lmp [A] : -DO- 6 Max. power Voltage Vmp [V] : -DO- 7 Short Circuit Current lsc [A] : -DO- 8 Open Circuit Voltage Voc [V] : -DO- 9 Temperature coefficient for Pmax [%/°c] : -DO- 10 Temperature co - efficient for Voc[% /°c] : -DO- 11 Temperature co - efficient for lsc [% /°c] : -DO- 12 Max. system voltage [ V] : -DO- 13 Manufacturer name : -DO- 14 Brand : -DO- 15 Country of origin : -DO-

Solar Pump Inverter :7


SL Model : To be mentioned 1 Rated Capacity : -DO- 2 Input Voltage : -DO- 3 Output Voltage : -DO- 4 Output Phase : -DO- 5 Output Frequency : -DO- 6 Maximum efficiency : -DO- 7 Ambient Temperature : -DO- 8 Brand : -DO- 9 Country of origin : -DO-

Pump Motor Specifications:-SL Pump Motor Specifications:-1 Motor Parameter To be mentioned 2 Model : -DO- 3 Motor Type : -DO- 4 Rated Capacity : -DO- 5 Input Voltage : -DO- 6 Phase : -DO- 7 Frequency (HZ) : -DO- 8 Max Speed (rpm) : -DO- 9 Maximum efficiency : -DO- 10 Maximum water temperature : -DO- 11 Brand : -DO-12 Country of origin : -DO-

Product Warranty:

a) Solar Module: 2 Years on material & workmanship Warranty, Power output Performance & warranty (10Years/90% & 20Years/80%)b) Submersible Pumps & Motor Warranty for 5 Years.d) Solar MPPT Inverter/Controller Warranty for 5 Years.b) All Other Equipments are Warranty for 5 Years.

Cable and Accessories:Cable for Pump Motor: 3 * 6 sq mm , 3 * 10 sq mm & 1 * 4sq mm or as specifiedCable for well Probe: 2 x 1.5sq mm for Pump dry ProtectionSafety Rope: Safety Dia 10mm polyester/ Stainless steel , 2000kg max load capacity.Safety Rope Connector: Safety Rope Stainless Steel Connector

Boring & Complete Housing for DTW:-Test boring will be perform by our expert or agencies to examine the water depth & flow rate and also 12"/200' bore hole piping up to 200' (Max) deep with necessary fittings and accessories for setting pumps.

Module mounting structure with structure base construction:

8


Footing:600mm x600mmBase Foundation: 600mm x600mm x150mm, On 150mm Sand Pad,75mm brick soling.75mm RCC with 10mm dia double base rod & 100mm C/C.Column: 200mm x200mm x900mm (750mm Underground) with 10mm dia rod & 5mm suspension rod150mm C/C. Use 200mm x200mm x 8mm Steel base Plate & 16mm dia 450mm length Anchor rod with washer-Nut.

Gread Beam:Gread Beam Size : 150mm x 150mm RCC using 10mm dia rod & 6mm dia suspension rod, every colum are incorporated.

Mounting Structure details:Fixed Structure for PV Module sun face direction, Size of the total module fixed tilt 23- 30°.All Structure are coated with hot-dip galvanizing to prevent from Oxidising &

CorrosionEarthing:Proper copper earthing is mandatory.

Civil and earth works

Inventory of needed works and basic allocation of potential system lots.

Techno-financial model Financial assumption: bill of quantities; works and services; Investing needs Grant needs Return on Investment calculations

The objective of the assignment is to propose and develop a technically feasible and financially sustainable model to displace grid-connected and diesel-powered irrigation water pumps in Bangladesh with efficient solar-powered pumps. The assignment’s scope covers PBS area of influence mainly. The model will include estimation of the amount of grant required to make the model sustainable and scalable in the future in Bangladesh.

1.2.2 The terms of reference for the assignment are summarised as follows:

Review other reports and information on solar irrigation in Bangladesh, and South Asia;

assess available secondary information to determine the quantum of financial subsidies given to farmers for irrigation water pumping in Bangladesh;

assess the technical feasibility of widespread introduction of solar-powered irrigation pumps in India in general and in Bangladesh specifically;

broadly assess the financial viability of replacing grid-connected and diesel-powered pumps with solar-powered pumps in Bangladesh considering the saved subsidies as a financial benefit to the state; and

develop a financial model for replacing grid-connected pumps in BD, incorporating the saved subsidy, financing from donors and financial contributions from users to the extent required to make such a scheme financially viable and sustainable.

9


1.3 Approach

During two field visits, the consultant have met with officials from the REB , nodal agencies for non-conventional and renewable energy sector, two electricity distribution companies (DESCO and DPDC), and major conventional and solar irrigation pump manufacturers. Visits were also made to several conventional and solar irrigation pumping installations within Bangladesh. Based on discussions during these meetings and visits and from publicly available information, analysis has been undertaken to confirm the technical suitability of and limits to solar-powered irrigation pumping. He also analysed the cost of existing subsidies and electricity bills for various classes of irrigation customers for various conditions of water table depth and irrigation areas. Next, he considered the size and cost of required solar photovoltaic (PV) arrays and replacement irrigation pumps. Finally, he analysed the expected financial outcomes for farmers, the government of Bangladesh and REB associated with the introduction of solar PV for irrigation water pumping.

1.4 Reporting

This DPP sets out the background to the project (this section) and outlines current agricultural irrigation practices in Bangladesh. It discusses the evolution and current status of solar pumping and outlines technology option and implementation issues (Section 6). Requirements for irrigation in Bangladesh are addressed in Section 4, and the power sector and the impact of demand for irrigation pumping are analysed in Section 5. Problems arising from current irrigation practices are discussed (Section 6), specifically the requirement for and impact of tariff subsidies. Section 7 looks at BD’s (have a look and if need please delete) solar resource and the suitability of solar PV for irrigation water pumping and Section 8 presents an analysis of the expected financial outcomes for stakeholders of the introduction of solar pumping and a discussion regarding suitable commercial models. Other challenges and barriers to solar pumping are discussed in Section 9.

A final report will be issued once comments and suggestions regarding the DPP have been made and incorporated.

1.5 Acknowledgements

The consultant acknowledges with thanks the cooperation and assistance of the Bangladesh Residential Mission of the ADB, the Energy Department of the Government of Bangladesh, the Rural Electrification Board (REB) .

10


2. Agricultural Irrigation in Bangladesh

2.1 Crops and Extent of IrrigationBangladesh is a lower riparian country in the flood plains of three great rivers the Ganges, the Bhramaputra and the Meghna, and their tributaries and distributaries. Water scarcity in the long dry season and sometimes drought even in the monsoon affects its agriculture, domestic and industrial water supply. This is primarily responsible for the shortage of water for agriculture. Moreover rural areas of Bangladesh suffer from lack of quality drinking water as surface water supplies are generally polluted and, therefore, have to depend on groundwater. About 90% of irrigation water in Bangladesh is provided from groundwater.

According to the Bangladesh Bureau of Statistics (2007), Bangladesh grows 46 economic crops of which rice are the dominant, producing more than 33 million tons annually. Besides, about 8.0 million metric tons of potato, 0.79 million metric tons of oilseed and 0.66 million metric tons of pulses are produced.

The cultivation of rice in Bangladesh varies according to seasonal changes in the water supply. With the increasing use of irrigation, there has been a growing focus on another rice growing season extending during the dry season from October to March. The production of this Boro rice, including high yielding varieties, expanded rapidly until the mid 1980s, when production leveled off at just below 4 million tons. Where irrigation is feasible, it is normal for fields throughout Bangladesh to produce rice for two harvests annually. Between rice growing seasons, farmers do everything possible to prevent the land from lying fallow and grow vegetables, peanuts, pulses or oilseeds if water and fertilizer are available. Groundwater irrigation plays a crucial role in agriculture of Bangladesh and thus in the national economy. Given its dense population and level of rural poverty, Bangladesh is very much in need of enhanced crop production. As far as the crop production is concerned, groundwater irrigation has contributed significantly to the cereal production, mainly

Boro rice and wheat, by supplementing soil moisture in the dry months of November/December to April/May. Thus cropping pattern is being moved towards HYV rice. Almost all of its 9.1 million hectares of net cultivable area, however, is already in use and any additional crop output can only come from increasing yield and/or cropping intensity. Methods that are available to achieve these ends depend he mainly on irrigation particularly minor irrigation technologies comprising low lift pumps (LLPs), deep tubewells (DTWs), shallow tubewells (STWs) and manually operated pumps (MOPs), which together are responsible for 85% of irrigation coverage in the country (Mandal 2006, Economic Review 2006). Thus groundwater irrigation is of vital imp0ortance as an input to the agricultural economy and for food security.

Current irrigation systems comprised of huge number of shallow and deep tubwells run either by diesel or grid connection or hybrid power system. However, due to Long terms operational cost and to find out Sustainable Energy Solutions, there is a timely demand to replace all those irrigation pumps by Solar power driven Irrigation pumps.

Therefore, it is attempted in this paper to examine present agricultural development and assess the irrigated crop economy with solar water pumping system in the lower Gangetic plain as a feasibility study.

11


2.2 Irrigation PracticesIn 1960, systematic irrigation started in Bangladesh with the introduction of low lift pumps & DTWs by the government employer Akter Hamid Khan in Comilla district. STWs came into operation after 1980, Bangladesh has a land area of about 14.4 million hector of which 9.03 million ha (64%) are under cultivation. Irrigation is currently available to less than 50% of the land that can be irrigated in the Rabi season.

Irrigation in Bangladesh was traditionally through surface water irrigation but with the introduction of high yielding rice varieties, ground water becomes an important source of irrigation water. At present, around 77% of irrigated land areas are through ground water irrigation. It is estimated that irrigated land areas could still be potentially increased by around 28%. Thus the potential for irrigation is relatively high.

The first solar irrigation pump in Bangladesh was installed in April, 2010 at Sapahar, Naogaon. The case study shows very motivating figures. The farmers were not interested to cultivate 3 crops round the year at that time. But after installing the solar pump the farmers was experiencing that they can go for the 3 crops easily. When the sun is available, obviously the water is also available. So you have plenty of water, now you need to use it. So you must have to change your crops pattern so that you can utilize the maximum benefits of the water that comes to you almost without a noticeable cost round the year. That’s the thing the farmers come to realize when they are been used with solar irrigation pump.

However, all solar pumps so far installed in Bangladesh implemented by IDCOL and BADC through different NGOs or companies who are allowed a good grant to make the project successful. And, in all most all cases, the installed pump is operated and maintained by a local Cooperative Society. The society has to pay a very nominal amount like BDT. 15000.00 (to BADC) per year to the NGO or to the company for using water by the pumps.

Methods of Irrigation commonly used in Bangladesh

Basin method : This method is widely used for rice irrigation. Border method : Used slightly sloping land. Furrow method : Suitable for line sown crops such as sugar cane, potato. Sprinkler method : Mostly suitable for undulated land & Hilly areas.

In Bangladesh about 94% of the irrigated land is under small and minor Irrigation.

Irrigation devices commonly used in Bangladesh as follows:

Motorized pumps (DTW, STW, turbine pump, low lift pump etc.) Manual pumps (Don, swing basket, treadle pump, hand tube well etc.)

Table 1 : Organization Wise Summary of Irrigation Equipment Used, Area Irrigatated : 2013-14

Organization Wise Summary of Irrigation Equipment Used, Area Irrigatated and Benefited Farmers: 2013-14

Type

of

Equi

pmen

t

Nam

e of

O

rgan

izat

ion Operated by Electricity Operated by Diesel TotalUnit Integrate

d Area (Ha)

No of Farmers

Unit Integrated

Area (Ha)

No of Farmers

Unit Integrated Area (Ha)

No of FarmersPDB REB TOTAL

DTW BADC 1033 9441 10474 281081 853643 1039 24092 52764 11513 305173 906407BMDA 985 13430 14415 322903 862439 0 0 0 14415 322903 862439Others 747 7543 8290 200222 775555 1816 48505 120767 10106 248727 896322Total 2765 30414 33179 804206 2491637 2855 72597 173531 36034 876803 2665168

STW BADC 3 42 45 376 500 10 36 121 55 412 621

12


BMDA 0 0 0 0 0 0 0 0 0 0 0Others 31931 241779 273710 941174 2904366 1290026 2337252 9145403 1563736 3278426 12049769Total 31934 241821 273755 941550 2904866 1290036 2337288 9145524 1563791 3278838 12050390

LLP BADC 56 874 930 55075 100858 4820 61081 125990 5750 116156 226848BMDA 12 40 52 731 2013 0 0 0 52 731 2013Others 721 8714 9435 141105 456925 155804 825543 2245187 165239 966648 2702112Total 789 9628 10417 196911 559796 160624 886624 2371177 171041 1083535 2930973

DTW+STW+LLP

35488 281863 317351 1942667 5956299 1453515 3296509 11690232

1770866 5239176 17646531

Manual & Artesian well

0 0 0 0 0 0 0 0 33778 35432

Traditional Method

0 0 0 0 0 0 0 0 0 28318 32000

Gravity Flow 0 0 0 0 0 0 0 0 0 101060 109735Country Total 35488 281863 317351 1942667 5956299 1453515 3296509 1169023

21770866 5402332 17823698

Source: Bangladesh Agricultural Development Corporation

With respect to the percentage share of land irrigated by different technologies, deep tube wells (DTWs) and low lift pumps (LLPs) were the dominant technologies used for ground water irrigation in Bangladesh in the 1980s. Shallow tube wells (STWs) on the other hand, introduced only in the 1990s, has become increasingly popular in the country accounting, at present, more than 60% of the total irrigated land area. This indicates that small farmers' share on STW ownership has increased significantly due to its low investment cost, easy installation, low maintenance cost and can be shared among small groups of farmers. STWs are convenient for small landholding owners, and restrictions related to the importation of these technologies were removed.

Groundwater irrigation:

About 75% groundwater irrigation About 74300 Mm3 of groundwater is needed annually for irrigation

Surface Water Irrigation – Current Practice and Issues

Service providers rent Low Lift Pumps (Centrifugal pumps) from local irrigation management organizations.

Pump availability is limited due to lack of wide spread pump and crop output market

Accessibility and affordability issues (mainly cost) Lack of adequate extension services focused on improved water and

agronomic management Lack of access to credit facilities

Large Scale Irrigation project in Bangladesh

G.K project: In1954 area: 1,97,500ha, Ganga & Kobadak river Tipaimukh Dam: In 2009 area: 15,626 ha Barak river in Sylhet. Chandpur Irrigation Project: In 1973 to 1978 area: 57,000ha; Meghna & Dakatia

river Barrindra Irrigation Project (BIP): In 2007 area: 7,500 acre; Bogra, Rajshahi Teesta Barrage Project: In 1945 area:7,50,000 ha; Teesta river.

The demand for irrigation water is increasing day by day & the cost is increasing accordingly. In present condition irrigation efficiency is only about 30%.

13


With proper utilization & improved management, 4 to 5 million hector of land can be irrigated easily by using the same number of irrigation devices instead of the present 3.12 million hector.

Literature review of farming practices and limited field investigations revealed that while farmers are aware of some kind of scheduling of water to the crops, their knowledge is based mostly on intuition and traditional wisdom, rather than on any scientific analysis or understanding.

In the non-grid area and due to the current high prices and price volatility of fossil fuels, the use of solar PV systems to power ground water irrigation systems becomes a cost-effective alternative in Bangladesh. The German International Development Cooperation (GIZ) estimated that there are around 300,000 diesel powered water pumps in the country that can be replaced by solar PV water pumps.

14


3. Solar Powered Water Pumping

3.1 Technological EvolutionAs per FAO estimation, in 2012 over 324 million hectares are equipped for irrigation, of which about 85 percent or 275 million ha are actually irrigated globally, contributing to irrigate agricultural lands that would not otherwise available for food production. Many pumping technologies have served the irrigated agriculture sector, from the early days of animal driven pumping to modern day solar PV powered irrigation. A wide range of pumping applications is in operation today, either to take water from a surface source to another location or to lift ground water from an aquifer.

The first reference and many subsequent cases of solar energy in water pumping relate to France, first reference being a solar steam engine demonstrating water pumping at the Paris Exposition in 1878.1 This technology was commercialised by a French company and is referred to in industry publications as recently as in 1970. Water pumping using solar PV as the energy conversion technology was also pioneered in France. By the late 1970’s the industry envisaged economic viability of solar PV water pumping if the array costs fell below US$ 5 per Wp of capacity (in 1978 dollars).

With a relatively low level of technology in power electronics in that era, the focus technologies have been direct current (DC) direct driven motors and solar-thermodynamic pumping. Thermodynamic pumping has subsequently become an obsolete technology and DC motor driven pumping is facing stiff competition from alternating current (AC) motor driven pumping technologies.

With a high cost of equipment, solar water pumping was seen in 1980’s as a contender for irrigation in sunny areas where the cost of diesel was high. However, solar water pumping took root well in low volume application such as village potable water schemes, providing an opportunity for equipment suppliers to further develop products, increasing reliability and reducing costs. By early 1990’s around 10,000 systems were in reliable operation around the world with 30-40% of the fleet serving developing countries.

Major factors contributing to changes in technology choices in solar water pumping are:

(i) the reducing cost of solar PV panels;(ii) the availability of consumer power electronics; and(iii) advancements in control and communication technology.

Early pumping solutions, which were essentially direct PV array driven DC motors, failed to make an important mark in the industry because of their high costs and the industry’s unfamiliarity with DC motors. The same is true today in spite of the relative efficiency and elegance of DC solution.

Figure1: Typical Solar Powered Irrigation Pump

1Solar Pumping: An Introduction and Update on the Technology, Performance, Costs and Economics. Barlow, Roy et al.15


Two clear technology paths in water pumping have emerged and it is very likely that direct array driven DC pumps and inverter driven AC pumps will continue to dominate the market in time to come. A comparison highlight relative strengths and weaknesses of these two technologies is shown in Table 1.

Table 2: Comparison of Solar PV Pumping Solutions

Attribute Technological SolutionDirect DC Motor Inverter AC Motor

Maturity Mature technology in limited use

Mature and widespread use

Reliability High on motor, medium on controller

High on motor, low on inverter

Serviceability Low, require special skills High, knowledge widely available

Start Up Inherently problem free High starting current, resolved using a VSD

Energy demand: supply balance

Partly achieved using sophisticated control technology.

Easily achieved using BANGLADESHPT with VSD energy optimisation strategy

Cost Relatively expensive Relatively affordable

Technical support Require special skills Less demand for special skills

Life Same for both technologies

Inter-changeability Limited, controller usually specified for motor

High, motor/pump can be replaced for given inverter

Maintenance burden Brushless DC motors feature electronic commutation, prone to failure. Could prove to be a severe burden

No electronic components in the motor

AC- alternating current; DC- direct current; MPPT -maximum power point tracking; VSD- variable speed drive

3.2 Global StatusSince the early days of solar PV technologies, the solar water pumping industry has evolved into a strong contender in rural water supply and irrigation sectors, primarily due to its ability to reduce fuel costs in fossil fuel based pumping systems. An expectation of steady increases in fossil fuel prices and consistent reduction of solar PV component prices mean that a complete transformation of this off-grid application is a possibility in coming years –

16


firstly in expensive diesel pumping sector and subsequently in other rural areas which are currently un-served by any pumping solutions provider.

In spite of these positive developments in the global water pumping industry, certain concerns remain under close attention of the industry. One such concern is the depleting ground water resources, hitherto preserved due to limited energy available for pump, constrained either by fuel costs or grid electricity curtailments. Another concern is the poor overall efficiency of irrigation systems, resulting from archaic practices, lack of investments and failure of the industry to provide more case specific solutions to users. Consequently, most pump solutions in agricultural applications operate at a point far away from the best operating point (BEP) desired and achieved in industrial pumping applications. Wide fluctuations of ground water levels coupled with lack of knowledge are combining to make pumping systems quite inefficient, often moving projects away from the margins of financial feasibility. Further, the large variety of pumps and motor configurations in service present after-sales support challenges; the solar PV water pumping sector will immensely benefit from an industry standard solution.

3.3 Application in South Asia and Bangladesh 3.3.1 Previous Initiatives

India

The first solar water pumping initiative in India took place in 1993-94 when the Ministry of New and Renewable Energy(MNRE, then called the Ministry for Non-Conventional Energy Sources or MNES) initiated a program for the deployment of 50,000 solar PV water pumping systems for irrigation and drinking water across the country. The programme was implemented through the Indian Renewable Energy Development Agency (IREDA) and the state nodal agencies (SNAs). Under the programme, MNRE provided the financial assistance required for subsidising the capital cost of the solar pump and the funds required to subsidise the interest costs. IREDA, as the implementing agency, channelled the financial assistance and interest subsidy received from MNRE as well as provided financing for the unsubsidised portion of the system costs from its own funds. In case the MNRE financial assistance and interest subsidy was routed through the SNAs, the IREDA financing for the unsubsidised portion of the system costs was not available for the end user.

During the first year, the programme was considered a demonstration programme and a target of 1,000 solar PV pumping systems were planned. However, less than 500 systems were reportedly installed during the first year. From 2004, the program was modified such that it became applicable only for community drinking water projects and the use of solar PV water pumping for irrigation was no longer applicable under the programme. However, the programme was not very successful in achieving the objectives. As of March 2012, only 7,771 solar PV water pumping systems were installed against the targeted figure of 50,000 systems.

The initial years of MNRE solar PV water pumping programme saw the programme being implemented mainly by IREDA, using non-banking finance company(NBFC) intermediaries who took advantage of the availability of capital subsidies, low cost financing and the 100% accelerated depreciation in Year 1 applicable for renewable energy technologies to provide the system to the end users at a concessional rate. However, after 2000, the programme was mainly implemented through the SNAs who were also able to bring in a component of subsidy from their respective state governments.

After the launch of the Jawaharlal Nehru National Solar Mission (JNNSM) in 2010, the solar water pumping programme of the MNRE was combined with the off-grid and decentralised component of the JNNSM. Under this programme, solar PV water pumping systems were

17


eligible for a financial support from MNRE through a combination of 30% subsidy and/or 5% interest bearing loans. The financial assistance was a 30% subsidy subject to a benchmark price of BDT 180 per Wp. Subsidy of 90% of the benchmark cost was available for special category states (that is, the north eastern states - Sikkim, Jammu & Kashmir, Himachal Pradesh and Uttarakhand). Several states have taken up initiatives to implement solar PV water pumping programmes using the financial assistance available under JNNSM and funds from the respective state government budgets.

Currently, India has an installed base of about 14,000 solar irrigation pumps. The state of Rajasthan has about 40% of the total installed base with other states including Punjab, Bihar, Uttar Pradesh, Tamil Nadu, Chhattisgarh, Karnataka and Kerala have the balance.

Sri Lanka

Under the Sustainable Agriculture Water Management Project (SAW MP )2, Sri Lanka’s Ministry of Agriculture implemented a project under which 10,000 solar-powered drip irrigation units (SDIU) consisting of a solar panel, maximum power point tracking (MPPT) charge regulator, a fertigation unit3 and a water pump, have been provided to small scale farmers in two phases. During the 1st phase, from 2005 to 2007, 5,000 SDIU were distributed to farmers in 14 districts. During the 2nd phase in 2008, another 5,000 SDIU were distributed to dry zone farmers in 17 districts.

The project was jointly funded by the Government of Australia and Australia’s Export Finance and Insurance Corporation (EFIC), in collaboration with BP Solar (Australia). The systems were supplied by BP Solar and were installed and maintained by the local agent of BP Solar. Typical end customers were expected to make a down payment of SLR 25,000 (~$200) and pay the balance in 114 monthly instalments of SLR 3,813 (~$30). Lower initial deposits and repayments applied to poor farmers.

Bangladesh

GIZ under Sustainable Energy for Development program of Power division, Grameen Shakti, Rahimafrooz and RDF started piloting this solar irrigation system in Bangladesh few years back. Back in 2012 SREDA cell of power Division took initiative to promote solar irrigation system in Bangladesh and they prepare a proposal to get financial support from Bangladesh Climate change resilience fund and jointly submitted proposal for financial assistance identifying IDCOL as implementing agency. That proposal was approved and accordingly IDCOL started solar irrigation program intended to provide irrigation facility to off-grid areas and thereby reduce dependency on fossil fuel and give an institutional shape. IDCOL has approved 445 solar irrigation pumps of which 156 are already in operation and 115 are under consideration. The remaining pumps are expected to come into operation shortly. Present program of IDCOL has a target to finance 1,550 solar irrigation pumps by 2017. The World Bank, KfW, GPOBA, JICA, USAID, ADB and Bangladesh Climate Change Resilience Fund (BCCRF) are supporting this initiative. IDCOL provide financing and technical support to implement the projects by different entrepreneurs.

IDCOL provided the technical, financial and promotional support. Under the program, pumps of 5–11 kW, operating at a total head of 12-15 m and capable of lifting about 300,000- 500,000 litres per day were installed. During the pilot phase, IDCOL offered 40% of the system cost as a subsidy. The implementer was expected to bring in 30% equity and the balance 30% was financed by IDCOL at 6% per annum repayable over 8 years.

2

3

18


Apart from IDCOL, Bangladesh Agricultural Development Corporation (BADC) implemented 11 Nos of Low Lift Solar Irrigation pumps in last two years, ranging capacity 3.7 Hp to 7.5 Hp. Average discharge by each pumps was determined to be 5 Lakh Ltr per day. Installed areas are Dhamrai, Mymenshing, Faridpur & Kishoreganj. As per field visit by this project, each pump is covering irrigation for land amounting near about 30~40 Bigha, however, during design the covering area was estimated to be 50~60 Bigha.

Figure 2: Solar Irrigation Pumps locations in Bangladesh

Latest solar pump projects initiative by BREB, Source: KOICA & Deasung Energy

Nepal

The Alternate Energy Promotion Centre (AEPC), a semi-autonomous body under the Nepal’s Ministry of Science, Technology and Environment responsible for developing and promoting renewable and alternate energy technologies, has been promoting solar PV pumping systems for drinking water and irrigation under the Energy Sector Assistance Programme. Under this programme, subsidies of up to 75% are provided for solar PV pumps for community drinking water schemes. As of July 2013, 177 systems had been installed.

Pakistan

Six community solar water pumping systems for drinking water of capacity of 4.8kWp were installed in Pakistan’s North West Frontier Province in November 2006. This project was funded by USAID and was implemented by Solar Energy International and Pakistan’s National University of Sciences and Technology.

UNDP, in association with Phaesun GmbH, had installed 200 water pumping systems in 12 districts in Pakistan. The project was aimed at providing clean drinking water and water for irrigation and livestock farming to communities affected by the 2010 tidal flood. The project was implemented from November 2011 to December 2012.

19


A pilot project for testing the feasibility of solar water pumping for irrigation was undertaken by the Directorate General Agriculture (Water Management) of the Punjab Government from 2010 to 2012. Under the programme nine water systems consisting of 1.8kWp solar arrays and 2hp motors were installed at government-owned farms.

3.3.2 Current InitiativesIndia

Under a program to install 17,500 solar PV water pump systems in the states of Rajasthan, Tamil Nadu, Andhra Pradesh, Uttar Pradesh, Maharashtra, Chhattisgarh, Madhya Pradesh, Bihar and other selected states, India’s MNRE announced a scheme4in March 2014 for the financial years 2015 and 2016 which provides a subsidy of 30% of the project cost (supply, installation and a 5-year on-site comprehensive maintenance contract) for pumps with a solar array capacity up to 5 kilowatt peak (kWp). This is subject to the requirement for relevant state governments to provide an additional subsidy of a minimum of 15% of the project cost. The scheme will be implemented through the respective SNAs. Thus, the minimum subsidy for a solar water Bangladesh system to the end user under this scheme would be 45% of the project cost.

MNRE has also announced another program5 to install 10,000 solar PV water Bangladesh systems all over the country, whereby MNRE will provide a 40% subsidy for pumps implemented through the National Bank for Agriculture and Rural Development (NABARD), co-financed by regional rural banks and other commercial banks at a nominal rate of interest. The financial assistance will be a 40% subsidy subject to a benchmark price of INR 190 per peak watt (Wp) of solar array (that is, the effective subsidy will be INR 76 per Wp). Under this program the end user will be required to pay a 20% contribution of the project cost.

Bangladesh

The power division of the Bangladesh’s Ministry of Power, Energy and Mineral Resources, has also announced an initiative to install 10,000 solar irrigation pumps to replace diesel pumps as part of the 500 megawatt (MW) solar power development in Bangladesh6 under the Asia Solar Energy Initiative (ASEI) launched by ADB.

In an effort to sharply reduce the use of conventional power, Power Division has initiated a move to install 5,00,000 solar-powered pumps across the country by 2020 for irrigation. The Power Division is currently moving ahead with a programme to replace about 1,50,000 diesel- and conventional electricity-run irrigation pumps with solar-powered ones by 2017. But, the new initiative has been taken recently to increase the number of solar-powered pumps under a power system master plan. ‘Our latest plan is to install 5,00,000 solar-powered irrigation pumps by 2020,’ said Siddique Zobair, joint secretary of the Power Division and a member of the Sustainable and Renewable Energy Development Authority.The capacity of each of the solar-powered irrigation pumps will be about 8 kilowatt peak and those would able to run for 5-8 hours a day to pump about 5,00,000 litres of water.The Power Division has been created SREDA as a new entity to promote renewable energy,

45

6 Power Division, Ministry of Power, Energy and Mineral Resources, Government of the People’s Republic of Bangladesh. Available: http://www.powerdivision.gov.bd/user/brec/50/91

20

http://www.powerdivision.gov.bd/user/brec/50/91


particularly the solar power across the country as green and sustainable energy. Of the 5,00,000 solar-powered irrigation pumps, some will be installed replacing the existing diesel-run ones and conventional electricity pumps while some will be installed as new ones in new areas, Power Division officials said.

The country has about 1.566 million irrigation pumps of which 2,66,000 are grid-connected electric ones consuming about 1300 MW electricity to irrigate 1.7 million hectares of land.Besides, there are 1.3 million diesel-run irrigation pumps which consume about 900,000 tons of diesel to irrigate 3.4 million hectares of land. Presently, SREDA has taken the move to install the 5,00,000 solar-powered irrigation pumps and already started working on the project to install them in both private and public sectors.

21


4. Agriculture and Irrigation in Bangladesh

4.1 Basic Structure of Crop Irrigation in Bangladesh4.1.1 Crops and Cropping Patterns

Cropping pattern is a sequence of crops produced throughout the year. Bangladesh has three crop seasons which are commonly termed as a) Rabi (November - February), b) Kharif I (March - June) and c) Kharif 2 (July - October). Ideally there could be only three crops that can be grown in a year. The main crops are local aman, kawn, oil seeds, jute and chili.

Crops cultivated in Bangladesh include cereals such as mainly wheat, rice, maize and oilseeds such soyabean and mustard. Commercial cash crops include cotton, sugarcane, vegetables such as potato, onion, green peas and garlic, and fruits including papaya, banana, and mangoes. Cropping pattern is given in Figure 4.

Figure 3: Cropping Pattern

Source: WFP, USDA & FAO

The dominant cropping patterns of Bangladesh are shown in the map above. Most areas allow three crops a year with the exception of the Sylhet hoar basin, the drought-prone areas in the west and the coastal areas. Rice is grown throughout the country with the exception of the Chittagong Hill Tracts. Wheat is predominantly grown in the north-west and in districts along the Padma river. The main vegetable producing areas are in the west around the town of Jessore.

4.1.2 Basic Water RequirementsIn estimating the irrigation water used in the country, emphasis was made on most prevalent crops, in spite of the country having a wide variety of crops. A further narrowing down of scope was made to separate winter crops for irrigation, as rain fed monsoon crops are much less dependent on irrigation water.

This project is characterised by several agro-climatic regions each with different irrigation requirements – for example, the southern region demands much less water than the north region. Actual irrigation water demand is determined by several factors, dominated by soil type, crop type and climatic conditions.

Based on the demand for harvest and actual ground conditions, it is advised suitable packages of agronomical practices for the farmer community. These recommended packages are used as guidance by the farming community, but of course actual irrigation

22


practices are decided by the famers themselves paying close attention to soil moisture levels, plant behaviour and weather conditions.

For the purposes of comparative analysis in this report, a simpler, generic approach was adopted to estimate water demand for the most extensively sown winter crops (shown in Table 2).

Table 3: Water Demand for Mixed Crops in Dry Season (Ltr/Bigha/day)

Crop Water Demand Mixed Crop 15,000 Ltr/Bigha /day

Source: Consultant Estimation based on field study

Table 4: Area Irrigated by Different Methods, 2007-08 to 2010-12 (Thousand acres)

Irrigation Methods

2007-08 2008-09 2008-10 2010-11 2011-12

Modern: 14182 14831 15315 16044 16584Power pumps 2560 2702 2696 2747 2887Tubewells 11622 12129 12619 13297 13697Canals - 875 871 - -Traditional: 963 14831 15315 860 851

Total 15145 15706 16186 16904 17435

Source: STATISTICAL POCKETBOOK OF BANGLADESH-2013

Further analysis established parameters that influence water Bangladesh energy demand, such as irrigation intensity and irrigation cycles employed. Considering the wide variation of irrigation intensity based on the soil type and actual plant behaviour, monthly water demand was estimated using the data from a field trial conducted on optimum irrigation practices

4.1.3 Water use:

In 2008, the total water withdrawal was an estimated 35.87 km3, of which 31.50 km3 (88 percent) was for agriculture, 3.60 km3 (10 percent) for municipalities and 0.77 km3 (2 percent) for industries (Figure 4-Left). Approximately 28.48 km3, or 79 percent of the total water withdrawal, comes from groundwater and 7.39 km3, or 21 percent, from surface water (Figure 4-Right).

Source: FAO-Aquastat Data Base, Bangladesh

23

Figure 4: Water Use


4.2.4 Identification of Underground Salinity Front of Bangladesh

Bangladesh Agricultural Development Corporation (BADC) has successfully identified the present state of underground salinity front for the first time in the country using latest technology. During 2009-2011, BADC has measured the latitude, longitude, Reduced Level (RL) and groundwater level of 3166 observation wells all over the country by using RKT GPS; constructed 168 salinity observation wells in the coastal belt and finally updated the zoning map and simulated it with RL. From the updated zoning map, it is revealed that in many areas of the country, groundwater levels have gone down below the mean sea level ranging from 0 to 52 meters. Some of these areas are connected among themselves and to the Bay of Bengal causing favourable conditions for saline water intrusion shown in Figure 1.

Figure 5: Underground salinity front at a depth of 33.84 m (110 ft).

Source: Journal by Dr. Md.Eftekharul Alam , Chief , MIISU, BADC, Dhaka

4.1.3 Irrigation Intensity

Theoretically, the best irrigation practice would be to apply water in desired quantities to all plants of similar maturity. This implies that a field of wheat sown in a day must be irrigated on one particular day, counted forward from the date of sowing. This requires a very large capacity that would lie idle for the rest of the particular segment of the irrigation cycle.

In practice, the plants manage to withstand dry conditions for several days. This limit is taken as ten days for wheat crops sown in table. This allows the spread of a particular water demand over a 10-day period, implying a pump of one-tenth the power than would otherwise be required. For the purposes of analysis and to better reflect practice in Bangladesh, a low intensity irrigation case was formulated to include a 12-day stretch of irrigation.

4.1.4 Irrigation Cycles There was documentary evidence, confirmed by farmers interviewed, that five irrigations spread over the 5-month long crop cycle was accepted as the norm, with an interval between irrigations of 21 days.

24


4.1.5 Modelled Water Demand

From the basic water requirements and other assumptions outlined above, water demand for analysis purposes was estimated as shown in Error: Reference source not found5.

Table 5: Modelled Irrigation Water Requirements in BangladeshCase Nov Dec Jan Feb Mar Total

mm/

mth

m3/ha/day

mm/mth

m3/ha/day

mm/mth

m3/ha/day

mm/mth

m3/ha/day

mm/mth

m3/ha/day

mm/mth

m3/ha/day

Low intensity

65 90 56 77 49 68 58 81 73 101 300 5,000

General 97 161 83 139 74 1---23 87 145 109 181 450 7,500

High intensity

140 280 120 241 107 213 126 251 157 315 650 13,000

mth = month

For the irrigation intensities used in modelling the energy demand for water Bangladesh, typical values were used. These values are subjected to change due to many factors, ranging from soil type to prevalent weather conditions of each crop cycle. The intensities used are presented in below, in litres per day, the most common unit used to define water flow rates.

Existing Water Pumping Bangladesh SolutionsIrrigation in Bangladesh is dominated by multi-stage submersible electric pumps. Where surface water or large-scale agricultural wells are constructed, horizontal centrifugal pumps are often used, driven either by an electric pump or a diesel engine. With the proliferation of ground water extraction using boreholes and submersible pumps, requiring little or no pipe network to link the water source to the cultivated land, surface water Bangladesh has become mostly an obsolete technology - some large bore agricultural wells were noted to be in a state of disuse.

Basic elements of a common irrigation pump can be identified as the wellhead structure (typically a frame made out of logs driven into ground to support the pump and power cables), a bore hole lined with a perforated pipe casing, the electric motor/pump assembly and the outlet piping from the pump located deep inside the bore hole to the surface.

Irrespective of the water level and seasonal fluctuations, the holes are bored deep into the earth, based on the financial resources available to the farmer. As a result, depths of bore holes show a wide variation. Accordingly, the number of stages in most commonly sold multi-stage axial flow and mixed flow pumps also vary. Investigation of pump vendor practices revealed that only the extent of land to be irrigated and affordability dictate the power of the pump, and the question of bore hole depth appears not to be considered.

The largest water lifting device for pumping groundwater for irrigation and domestic purposes is the deep tubewell (DTW). Generally, the well length is 60-90 m (200-300 ft), the engine Horsepower is 20-30 and the discharge is 56-84 lit/sec (2-3 cusec). The diameter of the pipe varies from 15-25 cm (6-10 inches). Turbine pumps are used for lifting water. They can be operated if the groundwater level is beyond the suction limit.

To irrigate a smaller area shallow tubewell is used widely. Generally, the well length is less than 30 m (100 ft), the engine Horsepower is 4-8, and the discharge rate is less than 28

25


lit/sec (1 cusec). The pipe diameter is 10-12 cm (4-5 inches). At present, shallow tubewells are used intensively in all parts of Bangladesh.

4.2 Energy Sources for BangladeshOther than a few solar installations and a large amount diesel pumps, the rest majority of irrigation pumps in Bangladesh are electric.

4.2.1 Grid-Connected PumpsTraditionally, grid-connected irrigation water pumps in Bangladesh have been permanently connected the local distribution network. In an effort to reduce rampant electricity theft by farmers and to extend the coverage area of the distribution network, in recent years discoms have been offering temporary or seasonal grid connections to farmers. Temporary connections are provided for four months from early November, and provide electricity for irrigation purposes over the winter cropping season. Temporary connections are low voltage (440 V) and three phase. Electricity is supplied to temporary connections typically for 10 hours per day on distribution feeders that are mostly separated from feeders for domestic supply. Farmers are responsible for providing and installing the electric wire required to connect from their pump installation to a coupling point identified by the discoms, typically the nearest distribution transformer. Farmers are also responsible for removing the connection after four months when electricity supply ceases.

They collect the full season’s revenue in advance from farmers for temporary connections and the average equivalent unit rate is slightly higher than for permanent connections. They take no responsibility nor provide any guarantees regarding service quality and safety beyond the coupling point. Officially, the length of the connections between a coupling point and a pump is a maximum of 150 meters but it is understood that connections often exceed 200 meters and sometimes exceed 500 meters. Consequently, energy losses on temporary connections are high, power factor is poor and voltages are well below the nominal voltage level of 440 V. The temporary pump connection visited, was approximately 150 meters long and had a measured voltage at the pump of around 300 V.

Although approximately 88% of irrigation Bangladesh connections and 86% of connected load are permanent, according to PDB Central permanent connections have not been favoured in recent years and temporary connections have been provided instead. This avoids the need and the cost of extending the distribution network, as would be required to provide permanent connections.

4.2.2 Diesel based Irrigation Pumps:During peak growing season, an additional 1.3 million diesel-run pumps are operated to irrigate another 3.4 million hectares consuming about 0.9 million tons of diesel per annum, worth $810 million, while creating $280 million in subsidies, and emitting more than 31 million tons of CO2 .7

This is a costly amount, which the government subsidizes at the expense of other agricultural innovations. Transportation of diesel to crop fields is difficult and the supply can be inconsistent. Farmers are often dependent on middle-men, who charge higher diesel prices during peak irrigation and cropping season and drive farmers further into financial difficulty. Diesel pumps also frequently break down, have high maintenance costs, and pollute the environment.

7 Emission assumption: 3,188 kg CO2 equivalent per ton of diesel fuel (World Bank estimates). 26


5. Issues with Current Irrigation Solutions

Irrigated agriculture has been playing a vital role for the growth in crop production in Bangladesh. Minor irrigation comprising of shallow tubewells (STWs), deep tubewells (DTWs), hand tubewells (HTWs) and low-lift pumps (LLPs) is a major irrigation system in the country.

Poor performance of irrigation is an issue for the expansion of irrigated area. Although many of the irrigation projects are technically sound in concept, it could not achieve many of the expected benefits due to a number of problems including:

o Heavy sedimentation in the intake channel of the Bangladesh plants;o Lack of regular power supply from national grido Insufficient water supply due to poor Bangladesh plant condition;o Inadequate and undependable power supply;o Inadequate tertiary and field channel network;o High operation and seepage losses from the canal system;o Poor system management, operation and maintenance;o Less than adequate extension services, farm inputs and agricultural credit;

ando Inadequate on -farm water management practices.o Poor Water distribution systemso Mostly unlined channelso A few buried pipe water distribution systemso Some lined channelso High water loss in distribution systemso Low system efficiency (Rice: average 30-35%; Other crops: 40-60%)

One issue that is rarely focused upon by planners is the huge demand for water and the associated energy demand as industrial activity expands and the country develops. That a huge water shortage is looming in the horizon has hardly been considered in national plans. Energy and water are essential ingredients for economic development and food production. According to the United Nations, by 2030 the world will need at least 30% more water, 45% more energy, and 50% more food. To meet the challenges of water shortage and supply large quantities of energy would be required.

Groundwater recharge is limited to only the monsoon months. Since recharge is a slow process most of the rainwater drains away. In the future, highly energy intensive mechanical recharge using giant pumps of underground aquifers may be required to ensure enough water for irrigation and other purposes during the dry season. This would more than double the energy requirement for irrigation.

However, electricity and Diesel play a vital role in operating irrigation pumps. Electricity for irrigation Bangladesh is sold to the users based on nameplate data or declared rating or, in certain instances, on consumption records witnessed by a utility representative at the commissioning stage. Any loss of efficiency in the system thereafter is not accounted for and is of no concern to irrigation customers.

Persistent low voltages, especially during periods of peak high Bangladesh demand, frequently cause pump damage and burnouts. Technology available in local repair shops for re-winding of motors appears to be relatively unsophisticated, potentially leading to further declines in pump motor efficiency.

27


Entrainment of silt and sand in pumped water leads to erosion of key components in the pumps such as rotating impellers and guide vanes. The technology path taken by the pump manufacturers to circumvent this issue is to produce pump components from low cost material such as moulded PVC. Here again, local repair shops are engaged in replacement of worn-out components and with apparent low levels of technology and knowhow.

5.1 Tariff SubsidiesBACKGROUND OF ELECTRIC POWER GENERATION SECTOR

The per capita energy consumption in Bangladesh is one of the lowest (321 kWH) in the world. As per Bangladesh Power Development Board (BPDB) installed Generation capacity (October' 2015) has increased to 11,877 MW. There are more than 87,319 villages in Bangladesh, and most of them are not connected to the national grid.

Table 6: Monthly Energy Generation Mix

Installed Capacity of BPDB Power Plants as on November 2015Fuel Type Capacity(Unit) Total(%)

Coal 250.00 MW 2.1 % Gas 7434.00 MW 62.59 % HFO 2507.00 MW 21.11 % HSD 956.00 MW 8.05 %

Hydro 230.00 MW 1.94 % Imported 500.00 MW 4.21 %

Total 11877.00 MW 100 %

Source: Bangladesh Power Development Board

Table 7: Electricity Tariff structure in Bangladesh

CONSUMER CATEGORY

RANGE (KWH)

BDT/MAR 2007

MAR 2010

FEB 2011

DEC 2011

MAR 2012

SEPT 2012

MAR2014

AUG2015

Domestic

00–75 2.5 2.6 2.6 2.73 3.05 3.33 3.33 3.8076–100 2.5 2.6 2.6 2.73 3.05 4.73 5.01 5.14101–200 3.15 3.3 3.46 3.81 4.29 4.83 5.01 5.36

201–300 3.15 3.3 3.46 3.81 4.29 4.93 5.19 5.63301–400 3.15 3.3 3.46 3.81 4.29 7.98 5.42 8.70401–600 5.25 5.65 5.93 6.88 7.89 9.38 8.51 9.98

Agricultural pumping

Flat 1.93 1.93 1.93 2.03 2.26 2.51 2.51 3.82

Small industry category

Flat 4.02 4.35 4.56 5.27 6.02 6.95 7.42 7.66Peak 5.62 5.95 6.28 6.75 7.33 8.47 9.00 9.24

Off peak 3.2 3.5 3.67 4.41 5.16 5.96 6.64 6.90

Source: Energy Regulatory Commission, Bangladesh

28

https://en.wikipedia.org/wiki/KWH

https://en.wikipedia.org/wiki/Energy_consumption

https://en.wikipedia.org/wiki/Capita


The Government subsidy:

Table8: Agricultural Subsidy during the Five Fiscal Years (in Crore Taka)

Fiscal Year FY2007-08

FY

2008-09

FY2009-10

FY2010-11

FY2011-12

FY2012-13

FY2013-14

FY2014-15

Agriculture Subsidy

2250 4285 3600 4006 4500 14130 14595 9000

Source: Ministry of Finance (MoF), GoB

Our government has provided a total of around Tk. 23,000 crore as agriculture subsidy for the development of agriculture sector in the past four fiscal years. For FY 2013-14, Tk. 9,000 crore had been allocated as agriculture subsidy. The targets of distributing agricultural credit for FY 2012-13 and FY 2013-14 are Tk. 14,130 crore and Tk. 14, 595 crore respectively. Total budget allocation Tk. 12,275.98 crore for FY 2013-14, development and non-development budgets combined, for the Ministry of Agriculture.

Agricultural input subsidy is a common element in agricultural development. The conventional argument for subsidies in agricultural development is that their primary role is to promote adoption of new technologies and thus increase agricultural productivity (Ellis, 1992). In Bangladesh, subsidy support for producers is provided on different agricultural inputs to boost up agricultural productivity. the electricity used for operating the LLPs (Low Lift Pumps) and STWs (Shallow Tube Well) to uplift underground water for irrigation, especially in the dry season. The costs of irrigation for Boro rice production are higher in Bangladesh. The higher prices of the electricity is the major concerns for giving subsidy to the producers in Bangladesh as incentive for production. It is also worth noting that the irrigation tariff is still significantly cross-subsidised by other consumers.

5.2 Water Resources 5.2.1 Water Resources in Bangladesh

Bangladesh can be considered to have abundant surface and ground water resources. The state can utilise annually approximately 22.7 billion m3 of water from the surface sources. 20% of the surface water available in the state is stored in ponds and lakes and the remaining 70% in the irrigation reservoirs. Before the success of green revolution, agriculture in Bangladesh had been largely a rain fed system. The monsoon rain impacted season from June to September was the season that was used to undertake the main cultivation effort. Systematic development of surface water based on the perennial river system of the country and ground water systems helped the country to achieve food security. Therefore, the economy and the environment of the Ganges-Brahmaputra-Meghna (GBM) basin region are crucially dependent on water.

The irrigation value of water as it is the major water use in this region and also it is more tangible and comparatively easier to measure than other uses namely fisheries, navigation and salinity control. Total pumping cost in the dry season is the lower bound of this value as some farmers are always willing to pay more than this value.

29


The country now has around 213 solar irrigation pumps, the majority of which were installed last year. An increased number of people are getting interested in solar irrigation pumps due to their financial viability and lower cost. The value of water for agricultural and industrial purposes is the marginal value product of water (MVPW), which is the value of an additional unit of water to the consumer. The value may be revealed by the users’ willingness to pay for water.

A farmer has to pay BDT. 3,000 - BDT. 4,000 for each bigha of land as irrigation charge during a crop season for diesel or electricity run pump, whereas for solar irrigation pumps it is BDT. 2,500-BDT. 2,800.00. The observation revealed that farmers are willing to pay for irrigation water sums at least equal to the process and maintenance cost and are able to pay up to the marginal value product of water.

In a study, it was revealed that TK. 3356.97 has been the mean value WTP of a number of WTPs data. Followings are the calculation of WTP with various household total income. For this the model is regressed seven time according to the household total annual income categories. And we can see that the estimated WTP is BDT. 3451.056 of those household who have annual income less then and equal to TK. 120,000, Similarly, we estimate the WTP as BDT. 3200.661 and BDT. 3298.522 of those household which have annual income less than or equal to BDT. 162250 and BDT. 231750. Again, BDT. 2509.228 and BDT.. 3580.102 are the estimated WTP for the household which have total annual income in between BDT. 162250; BDT. 120000 and BDT. 231750; BDT. 162250 respectively and BDT. 3475.727 is the estimated WTP for those households which have total annual income more than BDT. 231750.

5.2.2 Changes in Irrigation Patterns and Water Table ImpactsThe deepest water level monitored by the BADC in 2013 was 45 m. Out of the total population of monitored wells, more than 90% of wells show a water level less than 20 m throughout the year. The remaining wells also operate within a 40 m limit, reflecting the abundant water resources in the state.

Water levels undergo substantial changes between the pre-monsoon period and the post-monsoon period. Data published by the BADC indicates that seasonal fluctuations of water level from the mean are less than 4 m in most cases (for the population of monitored wells). Year-to-year and season-to-season variation of water levels is contained within 4 m depths in more than 90% of the wells monitored.

However, the average condition of the state’s water resource tends to conceal the issues in areas with marginal water resources.

30


6. Technical Analysis Solar PV Water Pumps in Bangladesh.

6.1 Present Status of Solar Energy Utilisation

Renewable energy in general, and solar energy in particular, came into focus in Bangladesh in 1985. Atomic Energy Commission, Bangladesh (AEC) initiated solar PV program (SPV) in 1985. The systems installed over the period 1985-1994 are 9790 watt peak. Most of the systems are not functional at present because of the lack of fund for spare parts, maintenance and back up service. As per Data found with Sustainable and Renewable Energy Development Authority (SREDA) presently 167 MW power is coming from Solar Energy.

6.2 Solar Energy Resources in Bangladesh: There is a good prospect of harnessing solar power in Bangladesh. In a recent study conducted by Renewable Energy Research Centre, it is found that average solar radiation varies between 4 to 6.5 kWhm-2day-1. Maximum amounts of radiation are available in the month of March-April and minimum in December-January. Following map has illustrated prospect of solar radiation in Bangladesh.

Figure 6: Annual Solar Insolation Map of Bangladesh

. Source: SWERA, UNEP/ GEF, RERC

31


Table 09: Monthly Global Solar Insolation at Different Cities of Bangladesh (in kWh/m2/day)

Month Dhaka Rajshahi Sylhet Bogra Barishal JessorJanuary 4.03 3.96 4.00 4.01 4.17 4.25February 4.78 4.47 4.63 4.69 4.81 4.85

March 5.33 5.88 5.20 5.68 5.30 4.50April 5.71 6.24 5.24 5.87 5.94 6.23May 5.71 6.17 5.37 6.02 5.75 6.09June 4.80 5.25 4.53 5.26 4.39 5.12July 4.41 4.79 4.14 4.34 4.20 4.81

August 4.82 5.16 4.56 4.84 4.42 4.93September 4.41 4.96 4.07 4.67 4.48 4.57

October 4.61 4.88 4.61 4.65 4.71 4.68November 4.27 4.42 4.32 4.35 4.35 4.24December 3.92 3.82 3.85 3.87 3.95 3.97Average 4.73 5.00 4.54 4.85 4.71 4.85

Source: Source : Dr. Shahida Rafique, Dhaka University, recorded from 1988 to 1998, Mondal, M. A. H., 2005, p.29, 2005

6.2.1 Estimation of Resource AvailabilityPersistence of daily insolation was next evaluated to determine a design value for insolation. The stream of data derived from the analysis was examined to determine the longest spells of overcast days and also to estimate the availability of a typical solar PV station. Because crop irrigation during the winter season would be the primary duty of the system, daily insolation values of the 5-month period November-March was filtered, leaving the low insolation monsoon months out of this analysis. The results of the analysis are shown in given below in Table . It is evident from the table that solar energy is a very reliable source for water Bangladesh, with only a single occurrence of a 7-day spell of low insolation during a period of a decade.

Table 10: Long Spells of Overcast Days

Year Month Duration of Spell Days

Insolation kWh/m2 per day

2002 January 2 <3.02003 February 4 <4.02006 December 4 <4.02009 January 5 <3.02009 November 4 <3.02009 November 7 <4.0

The data derived from the analysis was further examined to determine the design solar insolation for the Bangladesh solution. The daily insolation values during the winter season indicate that a level of insolation higher than 5.0 kWh/m2 per day can be expected to occur 90% of the time, as depicted in Figure 7.

Figure 7: Availability of Solar Resources in BANGLADESH

32


Source: Consultant’s estimates

Accordingly, a design insolation value of 5.0kWh/m2 per day was taken for estimation of array output.

6.2.2 Estimation of Array OutputInsolation data for the winter months and other environmental factors such as ambient temperature were used to model the likely electricity output from a typical poly-crystalline PV panel. Results are shown in Table . The results indicate a good potential to use solar energy resource in the location, and it was assumed that climatic conditions of this particular location is adequately representative of the solar energy incident throughout the state.

The assumptions made in performing this analysis were as follows.

Type of solar PV modules Poly-crystalline silicon Array efficiency 15%Inverter efficiency 95%Matching factor 0.9Temperature coefficient 0.005Array absorption coefficient 0.8 Array thermal loss coefficient 25 W/m2/ºCModule azimuth 23º (measured from South to West)Location 90º 23’ E, 23º 24’ NLocal standard time meridian 82º30’

The PV array mounting angle which gives out the highest energy output for during the winter irrigation season was found to be different from the angle of latitude (23º 24’) usually taken for year round energy optimisation.

Table 11: Estimated Monthly Solar PV Electricity Output in BANGLADESH (kWh/kWp per day)

Year Month Global(kWh/kWp per day)

Diffuse(kWh/kWp per day)

Direct(kWh/kWp per day)

2015 May 4.24 3.53 2.332015 June 3.27 2.46 1.642015 July 2.87 2.51 1.222015 August 3.99 3.52 1.612015 September 3.02 2.19 1.842015 October 3.21 2.11 2.44

Source: Institute of Fuel Research and Development (IFRD), BCSIR, Dhaka

33


The electrical energy outputs derived above were used to estimate the pumping energy delivery as well as the possibility of export of electricity to the grid during periods where pumping energy services are not required.

6.3 Solutions for Solar PV Water Pumping in Bangladesh

In rural and/or undeveloped areas where there is no power grid and more water is needed than what hand or foot pumps can deliver, the choices for powering pumps are usually solar or a fuel driven engine, usually diesel.

There are very distinct differences between the two power sources in terms of cost and reliability. Diesel pumps are typically characterized by a lower first cost but a very high operation and maintenance cost. Solar is the opposite, with a higher first cost but very low ongoing operation and maintenance costs. In terms of reliability, it is much easier (and cheaper) to keep a solar-powered system going than it is a diesel engine. This is evident in field where diesel engines lie rusting and unused by the thousands and solar pumps sometimes run for years without anyone touching them.

The first cost of solar is often daunting to donors and project implementers who are tempted to stretch their budgets as far as possible to reach the greatest number of beneficiaries by using a low first-cost option. But most would probably agree that “quantity over quality” is not a good value if the higher quantity option is not likely to be giving good service five years down the road and if beneficiaries are going to be stuck with interventions they cannot afford to sustain over time.

Solar pumping has had clear advantages for a number of years but the differences are becoming more striking in a world of rapidly escalating fuel costs. Not only will some of the world’s poorest people not be able to afford fuel for their pumps, but living at the end of remote supply chains, they may not even be able to get it in the first place as world demand overtakes supply.

In this section, we offer evidence accumulated by others as well as from our own experience showing that solar pumping is the most reliable and cost-effective option for many water pumping applications in developing countries.

As per Data found with Sustainable an renewable Energy Development Authority (SREDA) presently 167 MW power is coming from Solar Energy.

The government has also recently initiated a program to generate 500 MW of solar based electricity for the national grid. In this program, the private sector has been identified as an essential partner. The main components of this program include:

Replacement of Diesel Irrigation Pumps with Solar Power Solar Mini Grid Power System at Remote villages Solar Parks Roof-top Solar Power Solution for Commercial including government owned

buildings, Industrial and Residential buildings Electrification of health centers, educational Institutions, E-Centers at Union levels,

religious establishments and railway station

34


7. Water Pumping Energy Model Practical Data is under collection from the field and this part shall be prepared as soon as Data received.

7.1.1 Estimation of Hydraulic Duty

Practical Data is under collection from the field and this part shall be prepared as soon as Data received.

7.1.2 Selection of Design Month

Practical Data is under collection from the field and this part shall be prepared as soon as Data received.

7.2 Problems with Solar Irrigation Pumps and counter measures:

RemarksSolar pumps require a substantial up-front investment when compared to diesel pumps.

In effect, when purchasing a PV system people are buying many years of electricity up-front. At the time of purchase, you know to a large extent what your energy and pumping costs are going to be for the next 20 plus years (the life of the PV power generators).

Cloudy conditions affect solar irrigation pumps.

As a matter of fact during cloudy conditions, i.e., during the rainy season water is available naturally and therefore, use of solar irrigation pumps is not required

Insufficient water during dawn/morning hours when the land need to be wet to plough through.

Water reserved in reservoir can be solution to the need of water during morning

.

8.3 Technology ChoicesSourcing and application of water in crop irrigation involves a range of technology choices. Options selected for analysis in this report are described in the following sections.

8.4 Types of Pumps Considering the widespread use and versatility, multi-stage centrifugal submersible pumps were selected for analysis study. These pumps can extract water from depths down to 90m. Surface pumps, which require less energy than submersible pumps but perform at a lower duty, were not considered in the analysis.

8.5 Types of MotorsSubmersible pumps driven by three-phase induction motors were found to be the most widely used configuration in Bangladesh. Pump suppliers, vendors and officials were unanimous in endorsing this choice, and expressed strong opposition to newer and efficient brushless DC motors, citing high price, serous reliability issues and long repair delays. The industry’s view is that DC motors will not gain widespread acceptance until a strong support base is mobilised.

35


8.5.1 Water DistributionMost demand for irrigation in Bangladesh was for winter wheat crops. This crop, cultivated in vast, flat planes, is irrigated predominantly using a pipe and furrow method. The sector appears to be indifferent to ground water conservation issues, notwithstanding the significant water savings that could be made through better pipe networks. Sprinkler irrigation, which requires pump s to develop higher total dynamic head for proper operation, was promoted by state agencies involved in water management, but resisted by framers and pump solution providers. Accordingly, the study concentrated on high duty irrigation method of pipe and furrow, with an application efficiency of 50-60%.

8.5.2 Solar Energy Conversion EquipmentPrevalent practices in Bangladesh indicate that crystalline silicon panels are the dominant conversion technology. The reason behind the popularity is the low price, wide availability, higher efficiency, proven reliability and better aging characteristics.

Discussions with equipment suppliers revealed that sun tracking devices are no longer in high demand, since the comparative cost advantage is fast diminishing with decreasing module prices.

Given the wide acceptance of AC submersible pumps, inverters with variable frequency capability were chosen as the obvious control technology for the pump. The system efficiencies used in the analysis included the contribution made by a MPPT device.

7.3 SCOPE of Solar Water Pump against Diesel Pumps:

Every year, diesel pumps consume 1 million tons of diesel worth $900 million. This is a costly amount, which the government subsidizes at the expense of other agricultural innovations. Transportation of diesel to crop fields is difficult and the supply can be inconsistent. Farmers are often dependent on middle-men, who charge higher diesel prices during peak irrigation and cropping season and drive farmers further into financial difficulty. Diesel pumps also frequently break down, have high maintenance costs, and pollute the environment.

The minority of farmers, fortunate enough to own electricity-run pumps, also faces persistent power outages. This forces them to operate their pumps at night when electricity consumption decreases and power failures are less likely.

Farmers in some areas have been switching from diesel-run to solar irrigation pumps. By reducing irrigation costs, solar pumps are becoming popular, especially in areas without electricity grid coverage. Compared to their diesel counterparts, these pumps are also more reliable and easier to maintain. Farmlands that are not flooded during rainy season – and therefore suitable for 3 crops per year – are ideal for solar pumps, which can provide power for about 20 acres of land and 3 annual crop irrigations. And given Bangladesh’s fragmented land ownership, a group of farmers can associate to buy water from one irrigation pump. Solar-powered irrigation also reduces government’s fuel subsidy for the agriculture sector as well as diesel imports.

Therefore, solar pump is profitable and investment on solar pump is more risk free than diesel engine-operated pump. Diesel engine-operated irrigation pump emits carbon dioxide and pollutes environment, but solar pump is an environment-friendly irrigation technology. [1]

36


Bangladeshi farmers are facing many challenges from climate change. Variations in rainfall patterns and extreme temperatures have affected crop production severely. The situation only worsens without electrical grid coverage. Irrigation needs are always urgent: even a day without water could crack the land, damaging the quality and yield of crops. Till now, farmers have been mostly dependent on expensive and often scarce diesel fuel.

The solar pump technology is ideal for the country’s flat terrain which receives an abundance of sunshine. It is especially cost-effective in areas without electrical grid coverage, additionally reducing the government’s fuel subsidy for the agriculture sector.

The farmers are assured of irrigation for their crops, even on the most overcast days. The solar pumps enable an easy installation and transition from the traditional systems. They have no moving parts, function without noise or pollution and require virtually no maintenance.

By lowering their usual diesel costs by almost half, the impact of solar pumps is evident from the smiles of the farmers.

[1] Feasibility of solar pump for sustainable irrigation in Bangladesh, Int. J Energy Environ Eng (2015) 6:147–155 DOI 10.1007/s40095-015-0162-4, CrossMark

37


7.7 Area Selection for solar Pump installation:

Since solar Pumps can be run throughout whole areas, except the rainy seasons actually when water demand is very low, selected areas, Triple cropped lands circled in the map below:

Figure 8: Three Cropped land Areas in Bangladesh & PBS Locations in Bangladesh covering 5000 solar Irrigation pumps

Area Selection PBS Identification PBS IdentificationBrahman Baria PBS Meherpur PBSBagerhat PBS Munshiganj PBSChandpur PBS Mymensingh PBSChapainababganj Mymensingh PBSComilla PBS – 1 Mymensingh PBSComilla PBS – 2 Naogaon PBSDinajpur PBS – 1 Narayanganj PBSDinajpur PBS – 2 Narshingdi PBS -Faridpur PBS Narshingdi PBS -Feni PBS Natore PBS – 1Gaibandha PBS Natore PBS – 2Gajipur PBS Netrokona PBSGopalganj PBS Nilphamari PBSHabiganj PBS Noakhali PBSJaipurhat PBS Pabna PBS – 1Jalampur PBS Pabna PBS – 2Jessore PBS-1 Rajbari PBSJessore PBS-2 Rajshahi PBSJhinaidah PBS Rangpur PBS - 1Kishoreganj PBS Rangpur PBS- 2Kurgram - Lalmonirhat Sherpur PBSKustia PBS Shirajgonj PBSMagura PBS Tangail PBSManikganj PBS Thakurgaon PBS

Source: http://en.banglapedia.org/index.php?title=Crop

Table shows reference Pally Bidyut Samity (PBS) Operation offices from where installed irrigation pumps in three cropped land areas shall be operated.

38


Table 12:

Field Report:

It was found on ground that those farmers who have limited cultivating lands use diesel irrigation pump ranging from 2.5 Hp ~ 5 Hp, either by owning or renting. These pumps are small in size and easily portable from place to place, therefore, farmers can use the generator of the pumps for other purposes like driving “Nosimon”, Bengali name of tractor.

The solar water pump, is installed shall be operated only for 26~30 days of a year. Therefore, like multiple use of diesel generator that are used with diesel generators powered pumps, the solar power generated by PV modules can be feed back to the national grid by using grid connected or grid tie inverter.

Based Pump LLP: PUT PV AREA

Area/Space of Installation: As per field study the installed Solar Irrigation Pumps for a 3.75 Hp is 3 Katha. For 1.5, 3, 4 and 7.5 Hp pumps required land will be

Solar VS Diesel Pumps, a review:


Solar pumping has had clear advantages for a number of years but the differences are becoming more striking in a world of rapidly escalating fuel costs. Not only will some of the world’s poorest people not be able to afford fuel for their pumps, but living at the end of remote supply chains, they may not even be able to get it in the first place as world demand overtakes supply. In this paper, we offer evidence accumulated by others as well as from our own experience showing that solar pumping is the most reliable and cost-effective option for many water pumping applications in developing countries.

Limitation of Diesel Pumps:

Water layer Level VS Pump’s efficiency

CO2, solar vs diesel price, fosil fuel limitation, maintn, transportation, uncertinity

Limitations of Electric Pumps:

life time, limitation of generation, of-grid area etc.

39



Solar pumping has had clear advantages for a number of years but the differences are becoming more striking in a world of rapidly escalating fuel costs. Not only will some of the world’s poorest people not be able to afford fuel for their pumps, but living at the end of remote supply chains, they may not even be able to get it in the first place as world demand overtakes supply. In this paper, we offer evidence accumulated by others as well as from our own experience showing that solar pumping is the most reliable and cost-effective option for many water pumping applications in developing countries.

40


Table13: COMPARISON BETWEEN DIESEL AND SOLAR IRRIGATION PUMP

SL Pump Size (HP)

Discharge

(Per Sec in Ltr)

Discharge m3

Daily Discharge

(m3)Diesel: (8

Hr)Solar: (6 hr)

Cultivatable Land acre

(Mixed Crops)

Model Country of Origin Warranty Datasheet

Pump -Engine/Motor

Coupling Type

Efficiency

1

Diesel 2.5 3.5 12.6 100.8 4 Milton Pump Bangladesh 6 No

FlexibleRubber coupling

25-35%

Solar 1.5 5 18 108 4 -- USA/EU/UK 5 Annex: 1Shaft key and lock

Direct close63%

2

Diesel 4.5 6 21.6 172.8 7 China 6 NoFlexibleRubber coupling

25-35%

Solar 3 7.7 27.72 166.32 7 -- USA/EU/UK 5 Annex-2Shaft key and lock

Direct close64%

3

Diesel 8.5 10 36 288 12 china 6 NoFlexibleRubber coupling

25-35%

Solar 5 13.6 48.96 294 12 -- USA/EU/UK 5 Annex-3Shaft key and lock

Direct close63.40%

4

Diesel 12 16.5 59.4 475.2 19 china 6 NoFlexibleRubber coupling

25-35%

Solar 7.5 23 82.8 497 20 -- USA/EU/UK 5 Annex-4Shaft key and lock

Direct close60.2%

1


Production Cost by Diesel Pump:

With a 2.5 Hp diesel based irrigation pump the estimated cost of rice cultivated in the area of 4 Bigha is BDT. ... per kg, with subsidy on the investment.

Financial: With another chapter:

1


Conclusion:

The vision of the Government of Bangladesh is to provide electricity to all by 2021. To fulfill the GOB’s vision and objectives of electrification, development of renewable energy resources will play a vital role. The government has taken appropriate measures for generating environment-friendly electricity from renewable energy sources. The Renewable Energy Policy has already been approved with the target to produce 5% of the total power generation by 2015 and 10% by 2020 from renewable energy sources. In absolute numbers this means that at least 800 MW power has to be generated from renewable sources by 2015 and 2000 MW by 2020.

The agriculture sector of Bangladesh is a potential sector to implement sustainable energy initiatives. It is a promising sector where out of 11 million hectares of land under rice production, modern boro rice alone covers about 4.70 million hectares and nearly 98% of this area requires irrigation. The present demand of 33 million electricity operated irrigation pumps is about 1694 MW. However, power shortage and low voltage affecting irrigation from the electricity operated pumps causing lower production of crops. On the other hand, there are about 1.2 Million diesel operated pumps requiring 800 Million liter imported diesel per year. Considering the energy crisis of the country and increasing price of petroleum products across the globe, it is important to explore alternative energy sources for irrigation to ensure both food and energy security. In this context, the application of solar irrigation pump has tremendous potential especially to decrease the dependence on diesel, an expensive liquid fuel.

Solar powered irrigation system could be an innovative, economic and environmentally friendly solution for the agro-based economy of Bangladesh. This system mainly consists of solar panels & solar submersible pump. Solar panels utilize daily sunshine to generate electricity which in turn runs the solar pump to provide uninterrupted water supply. If a sun-tracker is used, it will help in maximizing utilization of the sunlight the panels receive. Initiatives has been taken by the Government for replacing all diesel irrigation pumps by solar irrigation pumps by the next 3-5 years.

1

Documents

Feasibility Study on Solar Irrigation Pump Project for REB by ADB