It's very simple & straight forward tool that helps me in calculating accurate cost savings while installing solar panels across my project sites by giving an exact value with respect accuracy level (AC/DC). I have never felt any difficulties or inconvenience using this program as it seems really user friendly! None so far!! If you are looking out for such useful programs please go ahead otherwise its just like wasting time because there might be better alternatives available over internet at reasonable prices which may suit your needs much more than ESE does. Cost saving analysis during site selection process - gives us precise numbers when deciding whether we should invest our additional funds into purchasing Solar Panels considering their expected ROI benefits - saves lot of paperwork too ;) Also helped decide location within the property where maximum number of roofs can accommodate required amount of installed panel area without compromising existing roof design etc!!