Need your $0.02 on charge controllers
Currently I have a 50 watt panel with a Sun Saver 10A charge controller. Based on my needs/wants/calculations/funds/roof space etc, I want to add another (2) 100-150 watt panels. I am going to do t...
Forum Discussion
pianotuna wrote:
To squeeze every watt requires a more expensive controller technology called MPPT. For 350 watts the Rogue mentioned above is about the perfect size. It will cost more to do MPPT than PWM, and the gains may only be around 8% according to the most pessimistic figures.
X2
A few notes:
45A controller is an overkill for 350W system.
Also, if you want to be sure that you get every watt you need not just an MPPT controller, but an efficient one. Rogue and TS-MPPT-45 (more powerful and more expensive alternative to Rogue) are efficient. $70-90 unknown box from Ebay - impossible to tell, there are no detailed data with graphs and numbers. Retailer may say on the website "99% efficient", meaning one particular combination of voltage and current, while in your application it might be less than 90%. Not to mention unknown reliability of unknown box. I like the analogy to Michelin tires - you get what you pay for.
As noted, if you decide to get MPPT controller, 24V nominal panel will be cheaper per watt (you can't use 24V panel with PWM controller of course). The problem is - 24V panels are mostly larger than 200W. 150W 24V panels are not very common.
