Simple to add 100 extra Watts of Solar

[NCeagle]

Here's a picture of a partially installed Zamp Obsidian 100 Watt panel on the front part of the roof.  This super simple addition doesn't require any changes to the standard Zamp 30 Amp charge controller or access port on the roof (there are only 2 of 3 ports used).  Anything additional will require an upgrade to a 50 or 60 Amp charge controller.  There's still a decent federal rebate for solar this year.

Before anyone goes crazy, I haven't finished mounting this yet.  I've got a question in to Jason about using some sort of stainless screws in addition to the VHB and then I'll seal it up with 3M 4200 just as Oliver did to the mounts on the other 2 panels.

[Overland]

Looks great. Their new panels certainly have a nicer profile. 

[SeaDawg]

That does look really nice. 

[mjrendon]

John,

It does look nice. 

I would be interested to hear what Jason recommends about the mounting technique if you don't mind sharing.

I am considering adding another PV like this or converting to a MMPT charge controller) for a up to a 25% efficiency gain over the ZAMP PWM charge controller.  The existing PVs that I am using are rated at 320W but they lose about 25% to the PWM controller (~80W loss max).  

The MMPT charge controllers run about $230 (30A) or $330 (50A) and supposedly provide a quicker and more consistent charging capabilities from what I have read. While the 30A controller allows for 440W (+120W available PV capacity at 12V), the  50A controller would allow for up to 700W if that is desired.  

I think either upgrade should have about the same impact on the total charging capability of the system since adding 100W of PV with a PWM controller is ~75W max at the batteries.

Mike

 

Edited November 27, 2020 by mjrendon

[John E Davies]

Nice looking panels, I like everything but the price ($500). Are you using the supplied mounting feet or something different? They make quick release mounts which would be helpful for when you have to do work up there, since these can't be tilted. Or can they?

https://store.zampsolar.com/collections/mounting-hardware/products/omni-mount-feet-quick-release

I do want to comment, adding extra panels up top is great for when you are actually exposed to the sun. I am going with a suitcase portable unit for when that is not the case.

Please post a full write up when you are done, I am sure lots of folks are interested. Thanks,

John Davies

Spokane WA

[NCeagle]

1 hour ago, mjrendon said:

John,

It does look nice. 

I would be interested to hear what Jason recommends about the mounting technique if you don't mind sharing.

I am considering adding another PV like this or converting to a MMPT charge controller) for a up to a 25% efficiency gain over the ZAMP PWM charge controller.  The existing PVs that I am using are rated at 320W but they lose about 25% to the PWM controller (~80W loss max).  

The MMPT charge controllers run about $230 (30A) or $330 (50A) and supposedly provide a quicker and more consistent charging capabilities from what I have read. While the 30A controller allows for 440W (+120W available PV capacity at 12V), the  50A controller would allow for up to 700W if that is desired.  

I think either upgrade should have about the same impact on the total charging capability of the system since adding 100W of PV with a PWM controller is ~75W max at the batteries.

Mike

 

Hi Mike, I agree that an MMPT charge controller is the way to go - especially as panels / solar capacity is added.  This is a quick and inexpensive upgrade (except for the $500 price tag on the panel - but if you take the 26% tax credit into account, the price comes down to $370).  Further upgrades would involve the "long" panels some have already installed.  The Obsidian 90 Watt long panels are a bit wider than the predecessor at just over 14", so I'm not yet sure if they would fit, but I definitely prefer the lighter weights since they are way above the center of gravity.  If they do, next year I'll consider adding those as well, and if I do I will upgrade to a higher amp Victron MMPT charge controller (or similar) at that time.  That would be a simple upgrade as well since all the pre-existing wiring could be used.

[NCeagle]

53 minutes ago, John E Davies said:

Nice looking panels, I like everything but the price ($500). Are you using the supplied mounting feet or something different? They make quick release mounts which would be helpful for when you have to do work up there, since these can't be tilted. Or can they?

https://store.zampsolar.com/collections/mounting-hardware/products/omni-mount-feet-quick-release

I do want to comment, adding extra panels up top is great for when you are actually exposed to the sun. I am going with a suitcase portable unit for when that is not the case.

Please post a full write up when you are done, I am sure lots of folks are interested. Thanks,

John Davies

Spokane WA

I'm planning on using the supplied feet, which are the quick release mounts that you shared the link for.  These definitely cannot be tilted like the bigger, 170 Watt panels that come with the solar package.  I also have a suitcase, but would prefer to get the most out of my rooftop and use the suitcase as a supplement when needed. 

I'd appreciate some thoughts on the following...  I noticed while placing the panel up on the roof that the mounts were just about flush with the mounts that are already there.  I could easily use that same mount for this new panel on the trailing edge - with a fabricated mount.  That would eliminate the need for any new holes on that trailing edge (I'd lose the "quick release feature" but not a huge deal).  I think using the existing mounts is a no-brainer.  I'd still have to drill holes on the leading edge mounts, BUT - maybe - since I'm anchored to the existing mounts, I could just double up the VHB mounts in the leading edge by using the 2 that I won't use in the trailing edge and avoid drilling altogether?  

Edited November 27, 2020 by NCeagle

[SeaDawg]

Back in the day, we were cautioned about adding in panels of varying sizes/wattage and different manufacturers.  Back then, controllers only recognized the  least of the panels' input. I'm not totally sure how this works, today . 

We've done three solar installations, all the same panels, within each install. 

 

Edited November 28, 2020 by SeaDawg

[Overland]

From what I’ve read and been told, for panels connected in parallel, the wattage of the panels doesn’t matter, but the voltages need to be the same, since the lowest voltage panel will bring the voltage of the entire array down. 

But all of Zamp’s panels have the same voltage regardless of their size, at least their standard ones. Not sure if the new line is the same, but I assume that it is. 

If you’re using a separate charge controller for the oddball panels, then I think anything goes. 

Edited November 28, 2020 by Overland

[SeaDawg]

I did some reading on this today, as we're thinking about adding more solar to the boat next year, but a different type of panel. Concensus seems to be exactly what Overland described above.

This article was fairly straightforward, with diagrams.  

https://solarpanelsvenue.com/mixing-solar-panels/