HOMER, the software for micro-power applicable as renewable energy optimization, was used to analyze solar water pumping system based on deferrable-load and primary-load methods at Giricahyo. The 12 kWp solar PV and 30 kW generator were used to power the standing-aline system.. Unfortunately, the system has been idle since 2010. Research to redesign and analyse solar water pumping system has been conducted by Ministry of Public Works together with the Department of Physics Engineering UGM to bring it into normally. Furthermore, this study was aimed to obtain recommendation and to conduct analysis on system performance using HOMER. As a result in deferrable-load method, generator is inappropriate to be implemented because fossil fuel will be very expensive and rare. Besides, the 12 kWp Solar PV could meet 31.4 % of demand load. In primary-load method, capacity shortage of 1.5 kW pump is at 3.2 % and 3 kW pump is at 9.9 % which means that to deal with fluctuation of solar radiation the use of the 1.5 kW pumps were recommended. The demand that can be fulfilled by 1.5 kW pump is at 22.4 %. Keywords: capacity shortage; giricahyo; HOMER; redesign; solar water supply system
