Pag 6 CIDA IN IRAUÇUBA
Autor: FÉLIX VASCONCELOS | Publicado: 2009-05-01T16:07:00-07:00

The Department of Natural Resources Canada (NRCan) received the mandate from the CanadianInternational Development Agency (CIDA) to help develop the groundwater resources of northeast Brazil,where some 25 million people living in an area the size of Ontario, are periodically affected by severedroughts related to the El-Niño phenomenon. Solar power will play an important role in this development.The NRCan/CIDA project, know as theNortheastern Brazil Groundwater Project isintroducing new technologies based on satelliteimagery and airborne geophysics to map thegroundwater resources over large areas quickly andefficiently. The airborne geophysics is proving to beparticularly useful because the groundwater isslightly saline in this region and behaves as aconductor that can be easily detected by thegeophysical methods.Being able to map the groundwater resourcesover large areas dramatically increases the amount ofwater available to the region, which traditionallydepended on wells drilled mostly near the villagesand farms that needed the water for humanconsumption and agriculture. But opening up theregion to groundwater development will also requirea new approach to water management because waterwells will now be drilled further from the consumers,most often away from the conventional electricalgrid that currently supplies only the major centres ofpopulation. In this water management scheme, it isclear that solar energy has a crucial role to play inbringing the newly developed water resources to theconsumers.Solar energy for water pumping is not new toNE-Brazil. However, it has not been used asextensively as one would expect considering theamount of available sunlight in the region. Onereason for this is that the only submersible motorsthat are readily available in Brazil to operate thepumps are alternate electrical current (ac) motors.With such motors, the direct current (dc) from thephotovoltaic modules has to be transformed into accurrent with a loss of efficiency.To improve the process, the NRCan/CIDAproject contracted Sunmotor International Ltd, aCalgary firm that specializes in solar energyapplications, to adapt one of its specially designed dcmotors to a line of popular Brazilian submersiblepumps. Sunmotor also developed a special motor tobe coupled with booster pumps for use with reverseosmosis equipment for desalinization. Groundwaterneeds to be desalinized before it can be consumed byhumans or used for irrigation in North East Brazil.Currently all of the thousands of desalinizationplants in operation in NE-Brazil use conventionalenergy, severely limiting their usefulness and leavinga large segment of the rural population withoutaccess to good quality water.To demonstrate the technology, a five-memberpartnership was established to build an experimentalsolar pumping and desalinization station in a smallfarming community in the state of Ceará in NorthEast Brazil. This community of about twenty-fivehouseholds has no electricity and obtained its waterfrom a well with dangerously high salinity, poweredby a windmill, until it broke down about a year ago.CIDA president Len Good converses with SunmotorInternational President Eric Jensen (dark shirt), at theinauguration of experimental solar pumping anddesalinization station in northeast Brazil. The windmill inthe background provided water to the community until itbroke down about one year ago.5Then, “survival” water was brought to communityby tanker trucks.In this experiment, a Sunmotor SUB500submersible motor fitted to a multi-stage centrifugalpump manufactured by Dancor S.A. of Rio deJaneiro, powered by nine 75 watt solar moduleswired 3 series x 3 parallel, is used to deliver some2600 litres per hour at a pumping height of about 36metres. For the reverse osmosis unit, a Procon rotaryvane pump model 2507, powered by a 1.5 h.p. 90volt, 1800 rpm dc motor connected to 18 x 75 wattsolar modules wired 6 series x 3 parallel is used todeliver 15 litres per minute at a pressure of 170 psi,as required for the efficient operation of the ROmembrane. The system will operate for a minimumof six hours per day under clear conditions, easilyachieving the target output of 1000 litres per day ofpotable water.The station was inaugurated on November 26,2001 by the President of CIDA, Len Good, in thepresence of representatives of all the Canadian andBrazilian partners in the project, the local governmentauthorities and the entire community. It is hoped thatthe station will be used as a model to be replicated inhundreds of communities throughout the northeast ofBrazil that could benefit from this technology. Theexperiment is also drawing a great deal of attentionat CIDA, and in March 2002, the station was visitedby the Minister of International Cooperation, theHonourable Susan Whelan.The use of solar power has a great deal ofroom for expansion in water and energy deficientnortheast Brazil, and Canadian technology andexpertise can be part of this expansion. The NortheasternBrazil Groundwater Project is looking atother applications of solar power, including inirrigation and long distance water transport.CIDA President Len Good surrounded by representativesof project partners and community residents in front ofthe PV array at the inauguration in the state of Ceará.Local resident fetching good quality water at the newlyinstalled solar pumping and desalinization station.75 watt PV modulesused to operate thepumping equipmentgc.ca/index.html>AcknowledgementsWe would like to express our special thanks to Eric Jensen,President of Sunmotor International Ltd., and FabioPeixoto Cavalcante of SOHIDRA, a branch of the WaterResources Secretariat of the state of Ceará, for providingthe technical expertise for this project. SOHIDRA is alsothanked for contributing the reverse osmosis desalinizationequipment, the water tanks, and all the excellent onsiteinfrastructure. Oderson de Sousa Filho of ServiçoGeológico do Brazil (CPRM), NRCan’s principal partnerin the Northeastern Brazil Groundwater Project, isthanked for his invaluable assistance with the variousaspects of the logistics. Rita Eugênia Martins Santiago,the Projects social program coordinator in Ceará, workedwith the Prefect of the Municipality of Irauçuba, EvaldoGomes Bastos and with the entire community ofLivramento to provide the very important social servicesfor this project. Finally, we are indebted to BobAnderson, CIDA’s Vice-President for the Americas, andall the CIDA personnel involved in the Americas Program,for their continuous support for the Northeastern BrazilGroundwater Project