I wrote a solar power system designer for small-scale solar projects. It started as a PC Parts Picker for solar panels, but I added a simulator and a few other features focused on solar power.
Would love to know what you think about it!
edit: here's the link: http://tiny-solar.space/
Looks good! Put in a similar requirements as I have on my sailboat and the system it spit out was pretty close to what I have working for me.
So happy to hear it! Are there any tools you'd like to see added?