Solar Pumping Systems (SPS) Introductory and ... - SSWM

1 Green EmpowermentSolar Pumping Systems (SPS) Introductory and Feasibility GuideWalt RattermanJonathan CohenAnna SW Yamhill StreetPortland, OR 97204P: (503) 284-5774 F: (503) 460-0450 July 2003 - Revised January 2007 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide Table of Contents: Introductory Overview of Solar Pumping Systems (SPS) What is a SPS? Typical Communities Using SPS Versus Other Pumping How Does a SPS Work? Steps in a system Description of the Important Terms and Example SystemsFeasibility Community Checklist for Your Technical What Are Your Resources? What Are Your Needs? Summary of the Design Can a SPS Handle Your Flow and Lift Requirements? What Size is the system ?Designing Community Community Development: Community Development: Roles and ResponsibilitiesPage 2 Page 2 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide Technical Determining Water Mapping the Community Aspects of Technical Aspects of Determining Total Dynamic Preliminary Array Summary of Design InputsBudgeting Community Development Project Equipment and Installation Budget Sustainability CostsWorked Design Example with Example Budget Example with WorksheetWhat s Next?

2 Review Vendor Proceeding with the Development Resource Dynamic Head Friction Installation for More InformationPage 3 Page 3 Green Empowerment Solar Pumping system (SPS) ----- Introductory and Feasibility Guide Summary This guide is intended for local NGO s and the remote communities they represent, striving to improve the reliability and quality of the community s drinking water. There are many ways to help a community to improve their drinking water supply. The information in this guide is meant to assist in examining whether or not a Solar Pumping solution is viable for your particular community. Throughout this guide, we stress the ideals of Green Empowerment in our work with local NGO s and communities: the goals of local leadership, social justice, and sustainability and the importance of community needs driving the project.

3 This guide is not to promote the use of Solar Pumping per se, but is to promote the proper and informed use of any technology that a community decides to utilize in order to reach their self-determined goals. Since Solar Pumping is one of the technologies that can assist in the all-important area of clean drinking water utilizing renewable energy, we have presented this information in the hopes that it will help with an overall understanding of the technology, and give a road map on how to proceed IF this technology matches with the needs and resources of the community. This guide is not a complete design and do-it-yourself manual. The goal of this guide is to enable the reader to make an informed decision about Solar Pumping . If Solar Pumping is an appropriate solution, this manual will help the designer assemblethe appropriate information with which to approach equipment vendors, donors, and technical consultants to proceed to the finalization of the design and initiation of the project.

4 The guide is broken into 4 main sections: introduction , Feasibility, Desing, and section should build on knowledge and provide checkpoints to help in the you are familiar with some of the information or wish to learn more at any point, followthe symbol to jump ahead. Worked examples and blank worksheets are also provided toassist in the process. Acknowledgments This guide was prepared by Walt Ratterman, Jonathan Cohen and Anna Garwood of Green Empowerment, and revised by James Willett. Thanks are also due to members of the Green Empowerment Technical Advisory Council: Windy Dankoff of Dankoff Solar and Matt Hamilton of SunPumps. Photo Credits: KyoceraSolar, Grundfos, Dankoff Solar , WattSun, and Solar4 Power. Page 4 Page 4 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide Overview What is a SPS?As more and more groundwater sources become unsafefor drinking purposes, potable water often needs to bedrawn from depths that require some form of Pumping .

5 ASolar-Powered Water Pumping system uses Solar energyto power a pump to supply a village with potable Pumping Systems are commonly used where it istoo far to walk to a well or where the well only providesseasonally usable water. An SPS is most beneficial whena community can come together to organize, build,finance, and manage the Typical Communities Using a SPST here are several characteristics that make a communitya good candidate for a Solar Pumping project. Thefollowing ideas will help you consider how yourcommunity s situation compares with qualities of asuccessful project. Currently, families must walk a good distance to obtainpotable drinking water. Existing wells are too shallow ordeeper wells would not work with typical rope pumpmechanisms. The people in the community work well together, with nodivisive groups.

6 The proposed project would provide servicesto ALL community members with no discrimination. There isgood local leadership and social justice values are high. The community is able to come together with a grouprepresentative, and organize to build, manage, and collectusage 14 Water is used for drinking, day-to-day uses and perhapsanimal watering. While large-scale applications like cropirrigation are generally not supported by an SPS, drip irrigationcan be. Not intended to bring indoor plumbing or drasticchanges in 18 The site has reliable Solar resources and relativelyexpensive, inaccessible, or inefficient alternatives. Forexample, fuel costs and maintenance for a diesel generatorare 5 Page 5 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide Does your project meet the above criteria?

7 If not, proceed with 6 Page 6 Green Empowerment Solar Pumping system (SPS) ----- Introductory and Feasibility Guide SPS Versus Other Pumping Technologies SPS PumpingAlthough a village may fit the profile above for a higher-technology Pumping solution like a SPS, be aware that a RangeSPS still may not be the best technology- consider the section 6d chart below to review some alternatives. Pros Cons Hand Pumping -Low cost -Simple technology -Easy maintenance -Clean -No fuel needed -Usable for hand-dug wells -Easy to install -Regular maintenance needed -Low flow rates -Uses community s time/energy -Poor use of machine-dug well Diesel Generator -Moderate initial cost -Easy to install -Frequent maintenance., expertise required -Short life -Fuel often expensive, supply intermittent -Noise, dirt, fumes -Overall (20 yr.)

8 Costs higher than SPS Ram Pump -Low cost -No fuel needed -Runs 24 hours a day -Low maintenance -Need appropriate site (falling water at a lower level, to be moved to a higher elevation) -Draws from open ground water Wind Turbine -Lower initial costs than SPS -Long life -Effective at windy sites -Clean -No fuel needed -High maintenance needs -Expensive repair -Parts difficult to find -Wind can vary seasonally -Lower output in calmer winds Solar PumpingSystem (SPS) -Easy to install -Reliable long life -Low Maintenance, simple repair -Clean -No fuel needed -Modular system can be closely matched to needs, expanded. - Solar energy can vary seasonally -Highest initial cost -Lower output in cloudy weather Page 7 Page 7 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide How Does a SPS Work?A Solar Pumping system uses electricity to power a pumpin a well. Solar Photovoltaic (PV) Panels transform thesun s energy into electricity to power the pump.

9 When itis nighttime or very cloudy, the PV panels produce noelectricity, so no water is pumped. To provide waterwhenever it is needed, extra water is pumped during theday and stored in a tank above the diagram on page 8 to follow the flow of electricityand water. More detailed information about pumpcomponents is given in section Steps in a SPSF ollow the flow of electricity and water to understand howa SPS works. The process is broken into 4 basic steps:Electricity Generation: Photovoltaic (PV) panels convertsunlight to electrical flow. The electricity then flows to acontroller, which monitors the water level in the well andstorage tank to ensure safe pump : If the sun is shining, the storage tank is notfull, and the well is not empty, the pump runs. Water ispumped from the water level in the well to the top of thestorage tank, a distance generally called the head or Storage: Water is stored in a large tank, usuallyset on a hill at a point that is high relative to otherlocations in the village.

10 It is best if the well is locatedclose to the location of the tank. Excess water is pumpedto the tank to provide water when the pump is beingserviced or cloud cover prevents electricity from beinggenerated. Storage is generally provided for at least twoto three days projected Points: The water tap or taps are the placeswhere the village residents come to gather water. Sincewe depend on gravity to carry the water from the tankthrough the piping system to the water points, the waterpoints need to be at a lower elevation than the bottom ofthe storage tank. This way, no additional electricity isneeded to distribute the water from the or HeadThe height that thewater is raised bythe from thewater level in thewell to the top inletof the storage PanelAn electrical deviceusually made withsilicon that convertssun energy intoelectrical energyPage 8 Page 8 Green EmpowermentSolar Pumping system (SPS) ----- Introductory and Feasibility Guide system DiagramSolar Panel ArrayElectrical Flow PathPumpWell CasingWater Storage TowerVillage Water TapLift or HeadSolar Panel ArrayPump ControllerKey Electricity Positive Line Electricity Negative Line Water LineNote.