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[ATHiker]

We have a 2015 Escape 21 with the ETI installed Go Power 160 watt solar panel. I am considering replacing it with a 200 watt panel. The 200 watt panel is essentially the same size and would be a straight forward replacement utilizing the existing roof brackets. How much real world benefit would I see with the more efficient 200 watt panel? I'm not sure about the Go Power, but the Delta Pro has bypass diodes.
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Go Power
Rated power (Pm) 160W
Efficiency 16.4%
Max power voltage (Amp) 18.60V
Max power current (Imp) 8.60A
Open circuit voltage (Voc) 22.50V
Short circuit current (Inc) 9.29A
Cell type Monocrystalline
Series fuse rating 20A
Weight 26.4 lb
Dimensions 59.1 x 26.3 x 1.97

Delta Pro
Rated power (Pm) 200W
Efficiency 19.98%
Max power voltage (Amp) 20.4V
Max power current (Imp) 9.80A
Open circuit voltage (Voc) 24.3V
Short circuit current (Inc) 10.2A
Cell type Monocrystalline
Series fuse rating 15A
Weight 26.5 lb
Dimensions 58.7 x 26.8 x 1.4

Thoughts, opinions would be appreciated.

[Centex]

What is the solar controller you are using with your current 160W panel, and will you be using that same controller with the upgraded PV panel (PWM or MPPT)?

What battery / batteries are you using?

With your typical use-habits how many hours of sunlight does it take for your current panel to replenish your battery array?

All go to trying to guestimate the benefit you might receive with the considered PV panel upgrade.

[ATHiker]

We are using the ETI installed Go Power solar controller (not sure of the model number, but it is 30 amp).

Batteries are Crown 6 volt AMG06220 (2).

Also have a 100 watt portable solar panel.

The last couple of years, we have not been able to camp as much as we like, so really don't have a lot of information. We're just trying to prepare for future travel which we expect to involve more boondocking. I thought that upgrading the existing roof mounted solar panel might be a good option, rather than trying to add another panel.

At some point in the future, we may want to change to lithium batteries, but I think that would necessitate changing the solar charger and the converter. These changes would exceed my capabilities........

[John in Santa Cruz]

Originally Posted by ATHiker

We are using the ETI installed Go Power solar controller (not sure of the model number, but it is 30 amp).

Batteries are Crown 6 volt AMG06220 (2).

Also have a 100 watt portable solar panel.

The last couple of years, we have not been able to camp as much as we like, so really don't have a lot of information. We're just trying to prepare for future travel which we expect to involve more boondocking. I thought that upgrading the existing roof mounted solar panel might be a good option, rather than trying to add another panel.

At some point in the future, we may want to change to lithium batteries, but I think that would necessitate changing the solar charger and the converter. These changes would exceed my capabilities........

thats undoubtably a ~18V PV PWM system. as long as your replacement panel has an open circuit PV under about 24V, and a max current voltage of around 18, you should be good to go. But 160W to 200W isn't much of a boost. I'm upgrading from the 160W GoPower system to a 360W LG panel, and replacing the PWM controller with a MPPT rated for well above the larger panel. Fitting the 360W panel on the roof is going to be a bit tricky, but I'm pretty sure I can do it.

[alanmalk]

Originally Posted by ATHiker

...
How much real world benefit would I see with the more efficient 200 watt panel? I'm not sure about the Go Power, but the Delta Pro has bypass diodes.
.
Go Power

Max power voltage (Amp) 18.60V
Max power current (Imp) 8.60A


Delta Pro
Max power voltage (Amp) 20.4V
Max power current (Imp) 9.80A

Thoughts, opinions would be appreciated.

Thoughts... Not sure the price & work involved are of much benefit.
Yes, the bypass diodes might help a bit if you camp in partial light shade, but they don't add anything in full sunlight nor in deep shade. They do their magic if one, or a up to a few, cells are shaded.

The other numbers aren't all that exciting either because: You have a PWM designed solar controller (as opposed to a MPPT controller). PWM can only take advantage of the extra current but not the extra voltage (a bit of an oversimplification to keep things easy). An MPPT would convert the extra voltage into usable power - but since you don't have it... So, you have an extra 1.2 Amps which is regulated to roughly the charging voltage of 13.8 volts = 16.56 watts of power - not the extra 40 you paid for.

Perhaps a second portable?

[MVA]

I was also in the midst in choosing a solar panel last spring. I compared spec, cost, etc. One of the most helpful forum members (you know who you are ) helped me in the selection by adding an additional critical criteria; returnability and customer service. Most panels (san Zamp) are all from China with unknown lineage. Hence, the ability to return the item if it is defective is paramount. I ended up with a Grape Solar 200W panel. Per John in Santa Cruz's comment, I paired it with a Victron MPPT controller.

2 cents

edit - purchased panel through Home Depot so returnability would be trivial.

[Centex]

Originally Posted by alanmalk

Thoughts... Not sure the price & work involved are of much benefit.

Tend to agree with this, Tom. Given the info provided you're looking at an additional ~1 Ah of charge to the battery per hour of ideal sun exposure (and you'll never have 'ideal sun exposure' throughout a whole day). I don't see the return value in that IMO very modest gain.

All other things being equal the PWM controller is the constraint, IMO. Gains could be increased with an MPPT controller which would utilize the 'excess PV voltage' to boost the amp output to the batteries, but that added expense still might not be worth the difference gained in this case.

[John in Santa Cruz]

FWIW, I believe the LG panels are made in Korea rather than China, but they are mostly aimed at the house/commercial market, and require MPPT controllers due to their 40V and higher PV voltages. they also tend to be a fair bit larger (my 360W LG360Q1K-V5 panel is 67" x 40" x 1.6", or 1700mm x 1016mm x 40mm).

[ATHiker]

Originally Posted by John in Santa Cruz

thats undoubtably a ~18V PV PWM system. as long as your replacement panel has an open circuit PV under about 24V, and a max current voltage of around 18, you should be good to go. But 160W to 200W isn't much of a boost. I'm upgrading from the 160W GoPower system to a 360W LG panel, and replacing the PWM controller with a MPPT rated for well above the larger panel. Fitting the 360W panel on the roof is going to be a bit tricky, but I'm pretty sure I can do it.

Thanks for your comments. I've been following your thread with interest.

[ATHiker]

Originally Posted by Centex

Tend to agree with this, Tom. Given the info provided you're looking at an additional ~1 Ah of charge to the battery per hour of ideal sun exposure (and you'll never have 'ideal sun exposure' throughout a whole day). I don't see the return value in that IMO very modest gain.

All other things being equal the PWM controller is the constraint, IMO. Gains could be increased with an MPPT controller which would utilize the 'excess PV voltage' to boost the amp output to the batteries, but that added expense still might not be worth the difference gained in this case.

I may look into replacing the PWM controller with a MPPT (I'm confident that I can handle that) and if it would support lithium batteries, if I go that route.

[Barylski]

hi john ,have you installed on -off switch from solar panel to controller and were did you install it ,thanks steve

[John in Santa Cruz]

Originally Posted by Barylski

hi john ,have you installed on -off switch from solar panel to controller and were did you install it ,thanks steve

I did. upper left corner of this wiring panel: