The Energy Electronics Institute of the AIST has opened its new web site PVSYSTEM.NET (http://www.pvsystem.net/ ) to present the up-to-date results of the ongoing development of the "Total Support Technology for Photovoltaic Power Generation Systems". This web site offers, in particular, a "Virtual Solar House on the Net" and a "Database with Example Data of Photovoltaic Power Generation Systems". With the benefit of the simulation techniques developed by AIST, the Virtual Solar House allows the user to predict the electric power output and to calculate the generating costs for his own photovoltaic power generation system.