Solar controller recommendations

[Ken Pole]

I have two 100W panels in parallel charging two AGM battery banks (house and starter) via a PWM controller. Hoping to switch to MPPT for improved efficiency and would appreciate brand recommendations. Yes, I do know MPPT is more expensive. Thanks in advance.

[Ken Pole]

Should also have explained that I want an MPPT controller capable of charging the two banks.

[Diesel Bill]

Check out the Renogy 40 amp Mppt controller for $119.00 I'm running 4 x 240 watt panels through 2 of these in a split port and stb. configuration. Working great so far.

[john61ct]

Victron SmartSolar 75/15

[ozsailer]

I was put onto the Fangpusan range of MPPT solar controllers. I ended up installing two of their 60 amp units and have been moren than impressed with their price and use. Highly recomend a look.


Greg H
lagoon 440

[Singularity]

The conventional wisdom is to use one MPPT per panel if possible to maximize capture (while redundant capability otherwise never hurts, if requiring more $ up-front). I bought a Victron because it is accessible with Bluetooth, plays well with other Victron components, and is widely employed. At around $110 I don't think that it's more expensive than other brands. I didn't research this too deeply other than to learn that some off-brand MPPTs are really PWM on the inside. Renogy and Fangpusan people seem to like their stuff (isn't Fangpusan just re-badged Victron?).

[ozsailer]

"Conventional wisdom is to use one MPPT controller for each panel" - sorry have never ever heard of this and never done an installation based on this. Can you advise where this is printed or how you came across this information.


Greg H

[john61ct]

It is a popular approach here on the forums, certainly not the norm out in the wider world.

Ideal for partial shade handling.

Yes takes up more room, and need to buy panels that deliver good value per SC or it gets expensive.

[daletournier]

I like the bluesky range. They are visually presentable which allows me to mount them in the open where they get good ventilation.

They also have alot adjustability such as switching from absorption to float based on end amps.

[Copacabana]

I have a Blue Sky 3000i and I'm very happy with it. It's more expensive than the Victron MPPT controllers, but I wanted a controller that displayed the data and settings on the controller itself. I like that I can see the battery voltage and amps in at a glance.

[john61ct]

Blue Sky is also one of the few charge sources that has "no Float, just stop" as an option when AHT is done.

I believe it requires the IPN-Pro Remote or UCM module in order to enable stopping the charge cycle based on EndAmps.

[Singularity]

Originally Posted by ozsailer

"Conventional wisdom is to use one MPPT controller for each panel" - sorry have never ever heard of this and never done an installation based on this. Can you advise where this is printed or how you came across this information.
Greg H

I don't mean to be curt, but I'd suggest googling it (keywords multiple MPPT shade efficiency). Some hits:
https://www.solarpowerworldonline.com/2014/02/dual-mppt-defined-understanding-mppt/
https://forums.sailboatowners.com/index.php?threads/partial-shading-two-panels-two-controllers.158915/

There's no smoke and mirrors with this....it's not just a boating thing or forum lore. If boaters don't use multiple controllers it's because they're okay with relatively less efficiency for maybe good reason (including financial, weight, space), or they just don't know better.

[john61ct]

The advent of Victron's pricing model, where several small but excellent MPPT SCs became actually cheaper than just getting one big central one, is really what made this idea more practical.

Matching a 75/15 up with a big single higher-voltage 200+W is what really brings great value.

Using old-school 20Voc panels designed for PWM, the MPPT doesn't give nearly as much an improvement, maybe 10% overall.

[Copacabana]

Originally Posted by john61ct

The advent of Victron's pricing model, where several small but excellent MPPT SCs became actually cheaper than just getting one big central one, is really what made this idea more practical.

Matching a 75/15 up with a big single higher-voltage 200+W is what really brings great value.

Using old-school 20Voc panels designed for PWM, the MPPT doesn't give nearly as much an improvement, maybe 10% overall.

I couldn't agree more! Coupling larger and cheaper higher voltage 200+ watt panels to a Victron MPPT is the best value on the market. Solar has never been so cheap.

I generate more power than I can use with two 45w panels with an Outback PWM controller and my recently-installed Canadian Solar 265 watt (30v) panel with the Blue Sky 3000i MPPT controller. I'm in float before noon on most days. Even on cloudy days I can keep up with my energy needs.

[RickG]

We are very happy with our Victron SmartSolar controllers. We use 330 watt panels, so went with the SmartSolar 100/30s.

Cheers, RickG