ENDOGENOUS RENEWABLE ENERGIES CONVERSION INTO ELECTRICITY FOR OPTIMAL PUMPING OF AQUIFERS GROUNDWATER IN THE SAHELIAN AREA: CASE STUDY IN BURKINA FASO

The water lack is a major obstacle to socio-economic development in the Sahel of southern countries. Water resources access being one of necessary conditions for the Sahelian space development, only water control is a lasting solution to Sahel development problem. Surface water being very ephemeral in the Sahel area, groundwater exploitation is essential for satisfying daily water needs, especially in rural areas. However, dewatering at optimal cost of groundwater faces the access to electricity problem, which is essential for pumping water. This work presents the optimization of a pumping system for groundwater stored in aquifers, to increase the offer of water resources access in Sahelian area, at a lower cost per cubic meter. The required electrical energy for pumping is produced from a hybrid electrical system, composed of photovoltaic solar and generator sets running on biogas, produced from animal droppings. The technical and economic optimization is done by Homer software. The simulation is carried out with four sites characteristics, located in the Sahel region of Burkina Faso, in West Africa. Simulation results gave water costs at the four sites: 0.152 $/m3 for Oudalan site, 0.184 $/m3 for Seno site, 0.151 $/m3 for Soum site and 0.152 $/m3 for Yagha site. This pumping system integrates environmental consecrations by calculating equivalent CO2 before and after conversion of biogas into electricity. CO2 quantity avoided is 134,244,818 tons per year. Biogas use in addition to solar photovoltaic as sources of energy for hybrid electric system has made it possible to lessen pumped water m3 cost and reduce significantly polluting and greenhouse gas emissions.