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Topic: Adding solar panel? (Read 1085 times) previous topic - next topic

Adding solar panel?

We have the 100 watt 12V solar panel setup from HF to keep our batteries charged.
NOW--my problem: A friend just increased/changed his solar panel setup and has offered me two 170 watt 12V  RV solar panels for $100. Can I just add/wire these in to my existing setup?
I did purchase and install the better monitor/controller when I put the HF setup on the roof of the coach.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Adding solar panel?

Reply #1 –
As long as they are wired in parallel you should be fine.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding solar panel?

Reply #2 –
I think that if you use the same controller on different wattage panels they will default the higher wattage panels to the lower panel.  So you might be limiting yourself to 300 watts total.  Might be better to buy another controller for either the existing panel or the new ones.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Adding solar panel?

Reply #3 –
Quote from: folivier –
I think that if you use the same controller on different wattage panels they will default the higher wattage panels to the lower panel.  So you might be limiting yourself to 300 watts total.  Might be better to buy another controller for either the existing panel or the new ones.
I don't believe this is correct especially if panels are in parallel .  The wattage output varies on each panel based on the light input.  Some panels might be in shade and have very little output and others might be in full sun and putting out nearly full wattage.  However, if the panels are put in series then if one panel in that series is in shade, it will bring the voltage down on the entire string.  So if the panels are the same voltage and are put in parallel and the controller and wiring can handle the additional wattage then there is no reason you can't use them.
2002 36' U270 Foretravel

Re: Adding solar panel?

Reply #4 –
Your controller must be able to handle the additional watt/amps. Not sure about the number of stages. What batteries are you using?
Plan ahead. You may want more panels in the future.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Adding solar panel?

Reply #5 –
Excerpt from the article

Connecting more than one solar panel in series, in parallel or in a mixed mode is an effective and easy way not only to build a cost-effective solar panel system but also helps us add more solar panels in the future to meet our increasing daily needs for electricity.

Mixing solar panels – Dos and Don'ts • SOLAR PANEL SECRETS EXPOSED

Dont know the guy nor any of his articles .. Not sure if he has a certificate of anything or all things electrical or solar. Not sure if he is a DIY type of guy or not so USE AT YOUR OWN RISK AND PLEASE VERIFY FOR YOURSELF> That is my Health and Safety broadcast as it has not been independently verified to say he knows or doesnt know what hes talking about..

Just covering myself here

Re: Adding solar panel?

Reply #6 –
I relied on this article when I recently went from 560 watts to 1187 watts 9 months ago.  Since then I added another 610 watts to 1797 watts now on my roof with mixed, mostly LG panels. I ran the plan I made, after reading the above link, bye AM Solar and they agreed that the numbers and plan were both correct. I am using 2 new LG (280 watt). 2 new LG (335 watt), and 2 used SunPower (305 watt) for a total of 1797 watts using two Victron controllers.  If I went with three controllers I could have 1940 watts. I bought the SunPower 305 watt panels off CraigsList, $100each and he delivered them to my door for $10 more each and helped me get them on to the roof.

Solar Battery Charging

Mixing solar panels – Dos and Don'ts • SOLAR PANEL SECRETS EXPOSED

As far as the writers creds, from their web site:  Lacho Pop, MSE, CEO and founder, has more than 15 years of experience in market research, technological research& design and implementation of various complex electronic and telecommunication systems. His large experience......in a manner that is both practical and easy understood by a broad audience.

He authored and co-authored several practical solar books in the field of solar power.....

Dimi Avram3Dimi Avram, MSE, co-founder, has more than 10 years of experience in engineering of electrical and electronic equipment. He has specialized....... various kinds of electric systems. His excellent presentation skills help him explain even the most complex stuff to anybody interested.
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: Adding solar panel?

Reply #7 –
Just saying for Reference.. DIY has been a bit of  a fiery topic and ...well not worth getting trouble again over something everyone that can read can figure out and make a choice on following or not.. Im a quick learner on some things.. Even with support to show someone had credentials in that are and were Experts it didnt help my plight .. so with every DIY I will post it up as I dont feel like being belittled again over something posted.

Re: Adding solar panel?

Reply #8 –
David, I like to say that I am not your average idiot but that I am an above average idiot.
In my case DIY usually has another i on the end: Do It Yourself Idiot.
I usually tried to hire people smarter than me. That way, when we got a job done others would think I was really smart.-----NOT
Didn't have to know everything, just where to find the answers to my questions.
If I don't know something I will ask and get answers from experts and people who have "been there, done that".
And you are one of my "go to people".
Thank you.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Adding solar panel?

Reply #9 –
You will not hurt anything. Buy them. For starters you could just lay them on the room and connect wires together parallel, all neg together, all pos together.

With big sun, you may not get full benefit, being limited by controller, but usually panels do not put out max, but with extra panels you will more often get max from controller. Some time later you can find another controller with higher watt limit.

You can do it yourself. Mounting will be a bigger challenge.

Re: Adding solar panel?

Reply #10 –
Mounting is not a problem. Used to work at an aluminum extrusion company and I can get 1-1/2x 1-1/2x 1/8 aluminum angle reasonable. Already used that for my 100W HF mounting and it works great.
I did it so if I need to clean under the panels, all I have to do is remove two bolts on the legs on one end and then tip up the panels
I pop riveted the angles together to create the frameworks. So all I have to do is alter the frames and still use the same feet that are screwed and glued to the roof of the coach.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Adding solar panel?

Reply #11 –
Oops, one picture short--didn't post
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Adding solar panel?

Reply #12 –
Quote from: nitehawk –
Can I just add/wire these in to my existing setup?
I did purchase and install the better monitor/controller when I put the HF setup on the roof of the coach.

You don't say WHAT solar controller you have. That would be the most important thing.
Solar charge controller's are sized by both the voltage of the array as well as the amps. If you don't have a large enough controller you won't get the full benefit and just produce heat.
While a mppt controller would be best imo it's not necessary if your just wanting to add some juice to the batteries. If you're looking to add real solar then a mppt controller will help you get the most out of your panels.
While adding panels piece meal can be done a better way would be to plan it from the start. Just depends on what you're looking for.

'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Adding solar panel?

Reply #13 –
May I sugggest you post what make and model solar charge controller you plan on using? A 10amp controller with 440 watts solar at 12 volts wired in parallel would not be a good plan.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Adding solar panel?

Reply #14 –
The DW and I talked last night.
Decided to not do the additional solar.
Reasons:
1. My new hip and arthritic knee won't allow me to climb up and down.
2. I seem to be a bit unstable with my legs and up 11' off the ground on a slippery fiberglass roof is not a good idea.
3. I will be 78 this July and don't heal as fast a I did when young.
4. For the way we use our coach why do we need more solar.
5. No place to add the extra battery(s) it would be needed to take advantage of the additional solar.
6. We don't have any residential appliances.
7. We never "boondock" more than overnite.
Told my friend to go ahead and sell the panels to "that other guy" that wanted them.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD
 

Re: Adding solar panel?

Reply #15 –
Not going up on the roof it sounds like a smart move. None of us young or old will do well falling off that beast. In that case that's when you pay somebody to do it. But as you say if you're not really boondocking and you're plugging in almost everywhere else solar is kind of a waste of money. One small panel to keep your batteries topped off is probably more than sufficient. and you probably don't even need that if you're plugged in all the time and you have a trickle charger for your start batteries.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired