Go Back   Thor Forums > Thor Brands and Products > DRV Luxury Suites
Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 05-24-2018, 06:42 PM   #1
Member
 
Brand: DRV
State: Texas
Posts: 73
Solar output

I installed four 150 watt panels with 8.2 aH output and a 60 amp mppt controller. On the maiden 3-week voyage, the most output recorded in the middle of the day, full sun, no clouds, and no shade was mid 400’s for wattage and upper 20’s for amps. Is that normal? Is it unrealistic to expect the full 600 watts and 33 amps?
__________________

clev is offline   Reply With Quote
Old 05-24-2018, 07:01 PM   #2
Senior Member
 
Bob Denman's Avatar
 
Brand: Thor Motor Coach
Model: Outlaw 29H
State: New York
Posts: 3,972
70% percent or so... That's probably about what you can expect.
That's not to say that you can't coax more out of it...
__________________

__________________
2018 Thor Outlaw 29-H
2018 Can Am Spyder 10th Anniversary Limited.
Good Sam Member 843599689
FMCA Member F473304
Bob Denman is offline   Reply With Quote
Old 05-24-2018, 07:06 PM   #3
Member
 
Brand: DRV
State: Texas
Posts: 73
Thank you, Bob.
clev is offline   Reply With Quote
Old 05-24-2018, 07:38 PM   #4
Senior Member
 
Bob Denman's Avatar
 
Brand: Thor Motor Coach
Model: Outlaw 29H
State: New York
Posts: 3,972
When it comes to solar power: I've been doing a lot of looking, reading, and shopping!
__________________
2018 Thor Outlaw 29-H
2018 Can Am Spyder 10th Anniversary Limited.
Good Sam Member 843599689
FMCA Member F473304
Bob Denman is offline   Reply With Quote
Old 05-24-2018, 07:48 PM   #5
Member
 
Brand: DRV
State: Texas
Posts: 73
Me too; I spent hours and days, mentally putting this system together. Tech support was/is useless.
clev is offline   Reply With Quote
Old 05-24-2018, 10:35 PM   #6
Senior Member
 
Brand: Thor Motor Coach
Model: Axis 24.1
State: Florida
Posts: 534
Panel ratings are in the lab at 77 deg F. Dust on the panels, haze partial shading and temperature all impact output.
The biggest item is battery sate of charge. This determines how much the batteries will accept at any given time.
There are also other factors that come into play also. But the above are the biggies.
__________________
2016 Axis 24.1 E-450 6 spd tranny
300 watts portable solar.
200 watts solar on the roof.
Wrangler JK dinghy
scrubjaysnest is offline   Reply With Quote
Old 05-24-2018, 10:57 PM   #7
Senior Member
 
Bob Denman's Avatar
 
Brand: Thor Motor Coach
Model: Outlaw 29H
State: New York
Posts: 3,972
You might want to check with Chance...
He's got MAD solar power knowledge!
__________________
2018 Thor Outlaw 29-H
2018 Can Am Spyder 10th Anniversary Limited.
Good Sam Member 843599689
FMCA Member F473304
Bob Denman is offline   Reply With Quote
Old 05-25-2018, 12:42 AM   #8
Member
 
Brand: DRV
State: Texas
Posts: 73
Scrub, thank you for the reply, and no offense, but I didn't understand a thing you posted. "in the lab at 77"????? "Dust, shade, hazing, temperature impact output"?? You did read, "New system, mid day, no clouds, no shade...etc"??? Right?? How does that answer my question?
clev is offline   Reply With Quote
Old 05-25-2018, 12:53 AM   #9
Member
 
Brand: DRV
State: Texas
Posts: 73
Bob, who is chance?
clev is offline   Reply With Quote
Old 05-25-2018, 02:30 AM   #10
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 2,981
Quote:
Originally Posted by clev View Post

....cut..... Is it unrealistic to expect the full 600 watts and 33 amps?
I’m no solar expert, not even close, but will say that for the typical RV installation it is indeed unrealistic to expect 100% of panel rating. Most RVs install panels flat on roof which is most practical, whereas the “ideal” rating tilts panels so they are perpendicular to sun. Depending on where you are in US, and time of year, that accounts for a significant power reduction.

Systems “may” also have enough voltage drop in wiring from panel down to controller that it becomes significant. Because you are working with low voltages and high currents, any voltage drop due to resistance in wire becomes a larger percentage of the power being transmitted through wire (compared to what we’re used to seeing).

Also, the sun doesn’t always shine with same intensity. Just because it looks sunny, it may not be as intense as what was used to rate the panel. This obviously also depends on where you are — further North usually less solar power from sun.

I have no idea what your system is, or where you did your test, but in general I'm impressed you are getting 450 watts out of 600-watt rating. Obviously my comments assume you did a typical RV installation with panels mounted horizontally.
Chance is offline   Reply With Quote
Old 05-25-2018, 02:59 AM   #11
Senior Member
 
wingnut60's Avatar
 
Brand: DRV
State: Texas
Posts: 254
Yes, 75% of rating is pretty good....
And dust/haze/high,thin clouds/horizonal positioning, not perpendicular to sunshine, all hurt the solar input. I take a look at my panels about every 3-4 weeks, and they are definitely dusty and have to do a little cleaning. Sometimes a good shower does it for me.
__________________
2015 38RSSA now it's our home
2005 36TK3--retired, but it was a good one
2017 F450 KR
wingnut60 is offline   Reply With Quote
Old 05-25-2018, 03:35 AM   #12
Member
 
Brand: DRV
State: Texas
Posts: 73
Thank you Chance & wing; very informative. Yes, my panels are mounted horizontal and connected to each other with 10 gauge wire. Final run from the roof to the controller is 4 gauge welder’s wire. Panels were clean and garaged up until we left on the trip. Texas to Indiana, then Ohio, KY, VA, and a southerly route back to Texas. I checked the controller a few times each day while traveling and parked. Output ranged from 200’s to 400’s watts and low teens to upper 20’s for aH. Having never had solar, I didn’t know what to expect.
clev is offline   Reply With Quote
Old 05-25-2018, 12:11 PM   #13
Senior Member
 
jpmihalk's Avatar
 
Brand: Thor Motor Coach
Model: Hurricane 35C
State: South Dakota
Posts: 921
That is pretty normal. We have 400W of solar on our roof but on a good sunny day get around 280 watts due to sun angle and dust buildup on the panels themselves. On cloudy/rainy days it is substantially lower (but still has some charging capability.)
__________________
John & Kerri
2016 Thor Hurricane 35C with our pups MacDuff, Piper and Annabelle
2017 Jeep Cherokee toad
FMCA - F457085
Blog - http://traversity.us
jpmihalk is offline   Reply With Quote
Old 05-25-2018, 12:32 PM   #14
Senior Member
 
Bob Denman's Avatar
 
Brand: Thor Motor Coach
Model: Outlaw 29H
State: New York
Posts: 3,972
Quote:
Originally Posted by Chance View Post
I’m no solar expert, not even close, but will say that for the typical RV installation it is indeed unrealistic to expect 100% of panel rating. Most RVs install panels flat on roof which is most practical, whereas the “ideal” rating tilts panels so they are perpendicular to sun. Depending on where you are in US, and time of year, that accounts for a significant power reduction.

Systems “may” also have enough voltage drop in wiring from panel down to controller that it becomes significant. Because you are working with low voltages and high currents, any voltage drop due to resistance in wire becomes a larger percentage of the power being transmitted through wire (compared to what we’re used to seeing).

Also, the sun doesn’t always shine with same intensity. Just because it looks sunny, it may not be as intense as what was used to rate the panel. This obviously also depends on where you are — further North usually less solar power from sun.

I have no idea what your system is, or where you did your test, but in general I'm impressed you are getting 450 watts out of 600-watt rating. Obviously my comments assume you did a typical RV installation with panels mounted horizontally.
This is Chance...
Thanks for chiming in at the exact right time!
__________________
2018 Thor Outlaw 29-H
2018 Can Am Spyder 10th Anniversary Limited.
Good Sam Member 843599689
FMCA Member F473304
Bob Denman is offline   Reply With Quote
Old 05-25-2018, 01:19 PM   #15
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 2,981
Quote:
Originally Posted by Bob Denman View Post
This is Chance...
Thanks for chiming in at the exact right time!

Glad to help, but there is a lot I also need to learn. I mostly understand the engineering fundamentals from when I was in school a very long time ago.

I did build a mean solar oven as a class project that could cook biscuits. And the total cost had to be really cheap — like $10 (back then) which made it tough to find materials that would work.
Chance is offline   Reply With Quote
Old 05-25-2018, 01:34 PM   #16
Senior Member
 
Bob Denman's Avatar
 
Brand: Thor Motor Coach
Model: Outlaw 29H
State: New York
Posts: 3,972
I figure that you know the "alternate fuel" stuff; even better than I know the best places to find good jokes!
__________________
2018 Thor Outlaw 29-H
2018 Can Am Spyder 10th Anniversary Limited.
Good Sam Member 843599689
FMCA Member F473304
Bob Denman is offline   Reply With Quote
Old 05-25-2018, 01:38 PM   #17
Junior Member
 
Brand: Still Looking
State: Virginia
Posts: 2
The only think I can add is;
Did you have any 12V items on? or was that just what the battery's were accepting as a charge.?
It could be possible you have more available but the battery's were accepting all they could.
Just because you have 600 watts and 33 amps does not mean it all being used.

Turn on some 12v items and see what the meter says.
kcmusa is offline   Reply With Quote
Old 05-25-2018, 02:55 PM   #18
Senior Member
 
juicesqueezer's Avatar
 
Brand: DRV
Model: 39RESB3
State: Florida
Posts: 106
I'm still learning, reading and asking about solar myself. The wiring has a lot to do with the amount of gain or loss, panels you select and battery bank you are depositing the solar into. There are a few YouTubers who have put in some killer systems and it gives a breakdown of what products they used, etc.
Hebard's travels and Pau Hana are two that come to mind.
I have been in contact with Brian Boone, who is an RVer traveling the country doing solar installs. People rave about his knowledge and installs. From what I read and understand, 70% is about right. Keep in mind that with the panels laying flat, any shade from the air conditioner, satellite dish, etc. affects those panels as well. I'm planning on 5 200 watt panels for my system. We already have a 5500 generator and have the Auto Generator Start system to work in conjunction with the battery voltage. Just my thoughts on the subject.
juicesqueezer is online now   Reply With Quote
Old 05-25-2018, 04:27 PM   #19
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 2,981
Quote:
Originally Posted by juicesqueezer View Post

.....cut..... Keep in mind that with the panels laying flat, any shade from the air conditioner, satellite dish, etc. affects those panels as well. I'm planning on 5 200 watt panels for my system. ....cut.....

Shade concern is a great point, particularly as systems get larger in capacity.

If looking at 1,000 watts of nominal panel capacity, and you wire them all in parallel, the amount of current can get pretty high — like around 50 Amps.

In large systems some “experts” go with combination of series and parallel, which can reduce current significantly (normally in half), but then it risks losing a greater percentage of total installed capacity if some of the cells are shaded.

I’d assume that since you are looking at 5 panels (and odd number), that you must be planning on going with an all-parallel installation. In that case shade is bad, but not as critical.
Chance is offline   Reply With Quote
Old 05-25-2018, 06:38 PM   #20
Senior Member
 
juicesqueezer's Avatar
 
Brand: DRV
Model: 39RESB3
State: Florida
Posts: 106
Quote:
Originally Posted by Chance View Post
Shade concern is a great point, particularly as systems get larger in capacity.

If looking at 1,000 watts of nominal panel capacity, and you wire them all in parallel, the amount of current can get pretty high — like around 50 Amps.

In large systems some “experts” go with combination of series and parallel, which can reduce current significantly (normally in half), but then it risks losing a greater percentage of total installed capacity if some of the cells are shaded.

I’d assume that since you are looking at 5 panels (and odd number), that you must be planning on going with an all-parallel installation. In that case shade is bad, but not as critical.
Not sure yet how to wire system and may add a 6th panel and split the system into two MPPT boxes. Decisions, decisions!
__________________

juicesqueezer is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by



ThorForums.com is not in any way associated with Thor Industries or its associated RV manufacturing divisions.


All times are GMT. The time now is 11:45 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0 PL2