STONE OF MACHADAO (MAR SHAR DAN )To reach the Stone of Machadao ( mar shar dan ), from the BR-222 Fortaleza, go to the Village Sao Jose, turn right into a big tower of telecommunication. The stone is at the end of the valley in front of a weir. There is a spring at the base, with water all year round. 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-Nino 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 Ceara 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