## 3 Available Photovoltaic Software
### Economic Evaluation Tools  
Software that classified as economic evaluation tools is able to provide economic analysis for the proposed system designed by the users. To determine whether the system is feasible or to maximize net benefit of consumption in the electricity services, user need to key in all of the cost and financial parameters as input, and then run the analysis. The analysis is needed to minimize total project costs to meet load demand or project constraints. One suitable software for simulation and data analysis of PV system is CalSol. The founder of this program is from the Institute National de l'Energie Solaire (INES), France. This software is able to run economic analysis on grid connected, standalone and DC-grid system. Unfortunately, only French meteorological databases are available in this software. Besides, as PVWatts, this software has no PV component database and other programs unable to interconnect with this software. This software is easy to handle, suitable for pre-sizing and it is free, since the software is available via internet [3; 50]. The Hybrid Optimization Model for Electrical Renewable (HOMER) is an energy modelling software, developed by National Renewable Energy Laboratory (NREL) USA. The software is suitable to design and analyze hybrid power system, including conventional generators, cogeneration, wind turbines, solar photovoltaic, hydropower, batteries, fuel cells, hydropower, biomass and others. HOMER can provide system optimization and technology options according to cost and energy resources availability. Moreover, this software able to simulate a system for 8760 h in a year and the results are presented in varies of tables and graphs. The meteorological data for the proposed site can be imported from HOMER energy website or provide specifically by the users. However, since Net Present Cost (NPC) analysis was used in economic analysis, comparison between other power system configurations in term of levelized cost of energy (LCOE) cannot be done. The developer provides a six months free version and then a renewal for 100 USD is required annually. [13; 14; 48; 51]  
In addition, RETScreen is also suitable as feasibility study tools for hybrid power generation technologies. Natural Resources Canada develops the software, and it is a Microsoft Excel-based spreadsheet model. The core of the tools consists of standardized and integrated clean energy project analysis that used in worldwide to evaluate energy production, life cycle cost, and green house gas emission reduction for various types of energy efficient and renewable energy technologies. The software also covers on grid and off grid analysis. Beside this, it has a global climate databasefor 6000 ground stations, and it also provides link to NASA climate database. Energy modelling analysis, cost analysis, emission analysis, financial analysis, sensitivity and risk analysis are available in this software. Unlike HOMER, the software can be used to compare levelized cost of energy (LCOE) between other power system configurations. RETScreen is a free of charge software, [13; 14; 48; 52]. System Advisor Model (SAM) is free software, developed by National Renewable Energy Laboratory, Washington. The software is able to analyze all solar technologies, as well as provide intensive financing and cost analysis. The results from the analysis will be presented in term of levelized cost of energy (LCOE), system energy output, peak and annual system efficiency, and hourly system production, in tables and graphs. SAM can automatically download online database, including energy resources for solar, wind, bio fuel, geothermal, US incentives and US utility rates [13; 53; 54]. PVWatts is automated simple calculator software, it gives quick answer for the expected energy production, and cost saving in grid connected system. PVWatts is a simplified version of PVForm, and it can be used trough SAM or via the Internet. However, PVWatts only allows users to select a location within United States or pre-determined list of locations only.