Valence U27-12XP questions

Welcome to the forum PeteB,

Can you tell us a bit more about your power needs?

Is this camping, RV, home, cabin, or something else?

Is this a roof fan, or are you looking at a fan to circulate air in the bedroom? (like a ceiling fan).

In general, if you can design a system that does not need a battery bank (like an attic venting system for use during daylight)--That saves money.

If you need night time/24 hour per day power, then picking appliances (aka fan) that uses as little energy as possible and still meet your needs, allows you to spend less money building and maintaining your system.

Here is a discussion that may get you some basic information about the Valance battery system:

https://forum.solar-electric.com/discussion/352804/valence-u27-12-xp-lithium-batterys

Lithium Ion batteries can be a "nearly ideal" battery (very efficient, very low self discharge, few "bad habits" regarding charging/discharging/sitting unused for a period of time). However, if you do not treat them correctly (and a battery management system can add complications), they are expensive and easy to damage/ruin too.

-Bill