In April 2001 LABSOLAR installed the first hybrid Diesel / PV system without storage in the Amazon. This 20.4kWp PV installation was added to an existing Diesel mini-grid to demonstrate the economic and technical potential of designing medium to large systems without battery banks for the supply of villages in the Brazilian Amazon region, where hundreds of mini-grids fed by Diesel thermal units exist [4,5]. In this particular case, the daily load to be covered amounted to some 700kWh, with two 56kVA Diesel gen sets providing constant power to the mini-grid, with the line-commutated sinewave inverters connecting the PV system to this grid whenever there is photogenerated power available to be fed to this mini-grid. For small PV penetration levels like the one proposed in this project, it was demonstrated that the absence of battery storage can be an advantageous strategy, with economic and environmental benefits in terms of reducing Diesel