Thor Forums

[scrubjaysnest]

Originally Posted by FollowTheSun

Thank you for the comment. My decision to use a MPPT controller, instead of PWM, is based on various operational inefficiencies (seasonal, shading, dust, ect.) and not cost. These criteria might change as I gain a better understanding of the very limited roof space available for solar. There also still remain several other variables, related to such as battery type and average daily load estimates. In actual fact, my current estimate for 300 watt panels may even change. However, at the moment, the most critical question, for me at least, relates to what space is available for panel installation. ... I'm sure you understand my problem at the moment ... what we want and what we can have are often at odds. At the moment, much of my wish-for specification relate more to my budget and what I want, rather than what I can or should have.

With shading panel output drops by 90% that is why we use 2 - 100 watt portables until we get home this winter. Parallel wired panels will do better then series wired so you loose the advantage of higher input voltage for the MPPT.