Solar Panels

[homelesshartshorns]

Can someone show links to the type of solar panel and the gadgets I will need to simply keep my house batteries up. 

[fpmtngal]

That’s an incredibly open-ended question!  There’s many answers to that question, it depends on why you are asking that question and what it is you are trying to do.  How big is your house battery bank?  Are you looking for a way to keep your batteries charged when your RV is in storage outside?  Or is your converter failing and you want to run the 12V system on solar instead of shore power (I’ve done that)?  Are you looking to overnight occasionally without shore power?  

Anything electrical makes my head swim and my first attempt at solar was done wrong (undersized wiring and too long wire runs - something I never considered).  I ended up going to a good solar installer (AM Solar but there are others equally good) who worked with me about what I wanted and did the install.  I’ve added to my system a couple of times and am now thinking about another addition, but that’s because my needs are changing.  I think if you give more particulars, others will give you much better information than I can.

[dennisvr]

You will need to add a little more info to your statement (what I need to keep my house batteries up).  Thats like asking how far I can go on a tank of gas............

[homelesshartshorns]

1 hour ago, dennisvr said:

You will need to add a little more info to your statement (what I need to keep my house batteries up).  Thats like asking how far I can go on a tank of gas............

Im currently using a Honda eu1000i generator to run my toys and bring up the house batteries. I would like to do this with solar! I think the Honda puts out 80 amps! I see on my wall monitor with the generator running it say 4 amps being used? So I'm thinking I'm not using a lot of power. Does this state my case?

 

[Kirk W]

40 minutes ago, homelesshartshorns said:

Im currently using a Honda eu1000i generator to run my toys and bring up the house batteries. I would like to do this with solar! I think the Honda puts out 80 amps!

A generator supplying 1000 watts of energy puts out a maximum of 8.3a at 120V. That could be near 80a from your 12V converter. 

Edited September 26, 2022 by Kirk W

[homelesshartshorns]

30 minutes ago, Kirk W said:

A generator supplying 1000 watts of energy puts out a maximum of 8.3a at 120V. That could be near 80a from your 12V converter. 

Ok.

[homelesshartshorns]

Thanks I guess I try somewhere else.

[Chad Heiser]

Do you have a battery monitor to give you good information about how much energy you use from your batteries?  Can you tell us what size your battery bank is?  My typical recommendation for basic battery maintenance while in storage is between 100 and 200 watts of solar.  Storage is obviously different than actually using the RV.  For using the RV with lead acid or AGM batteries, I typically recommend double the solar wattage to the amount of battery amp hours.  So if you have a 200 amp hour battery bank, I would recommend 400 watts of solar.  This is a general rule of thumb, but it usually works pretty well.

As to what equipment is needed, that is fairly simple.  You need solar panels and solar panel mounts, wiring between the solar panels (if more than one), then wiring from the roof down to wherever the solar controller will be mounted.  The solar controller should be a quality MPPT style controller.  You should have circuit protection between the panels and solar controller and then also between the solar controller and battery bank.  Finally, you need wiring between the solar controller and the batteries.  This will be a heavier gauge wire than that coming down from the roof.

Mounting the panels to the roof is dependent on the type of roof you have.  Most RV’s have rubber membrane roofs.  This type of roof requires Dicor or a similar sealer, stainless steel screws and typically aluminum mounting brackets.  Put a bead of sealer down, set the mount in the bead, screw the mount down and then cover it all in sealer.

I have a lot more information about solar on my website listed below under the Learn section.  Feel free to ask any specific questions you might have.

Edited September 26, 2022 by Chad Heiser

[homelesshartshorns]

1 hour ago, Chad Heiser said:

Do you have a battery monitor to give you good information about how much energy you use from your batteries?  Can you tell us what size your battery bank is?  My typical recommendation for basic battery maintenance while in storage is between 100 and 200 watts of solar.  Storage is obviously different than actually using the RV.  For using the RV with lead acid or AGM batteries, I typically recommend double the solar wattage to the amount of battery amp hours.  So if you have a 200 amp hour battery bank, I would recommend 400 watts of solar.  This is a general rule of thumb, but it usually works pretty well.

As to what equipment is needed, that is fairly simple.  You need solar panels and solar panel mounts, wiring between the solar panels (if more than one), then wiring from the roof down to wherever the solar controller will be mounted.  The solar controller should be a quality MPPT style controller.  You should have circuit protection between the panels and solar controller and then also between the solar controller and battery bank.  Finally, you need wiring between the solar controller and the batteries.  This will be a heavier gauge wire than that coming down from the roof.

Mounting the panels to the roof is dependent on the type of roof you have.  Most RV’s have rubber membrane roofs.  This type of roof requires Dicor or a similar sealer, stainless steel screws and typically aluminum mounting brackets.  Put a bead of sealer down, set the mount in the bead, screw the mount down and then cover it all in sealer.

I have a lot more information about solar on my website listed below under the Learn section.  Feel free to ask any specific questions you might have.

You comments are very helpful, thank you.

[Chad Heiser]

2 hours ago, homelesshartshorns said:

You comments are very helpful, thank you.

Your welcome.  Let me know if you have any specific questions.

[bruce t]

You have to work/think backwards. Before asking about "how to" you need to ask "what do I need". No point designing a system if you don't know how big, or small, that system needs to be. The internet is full of calculators for figuring out power needs for RVs. We get by just fine with 200watts of solar and 200amps of battery. But I know folks who struggle with 1000watts and 100amps. 

Figure out your needs and the rest is "easy"!!!

[Randyretired]

10 hours ago, bruce t said:

You have to work/think backwards. Before asking about "how to" you need to ask "what do I need". No point designing a system if you don't know how big, or small, that system needs to be. The internet is full of calculators for figuring out power needs for RVs. We get by just fine with 200watts of solar and 200amps of battery. But I know folks who struggle with 1000watts and 100amps. 

Figure out your needs and the rest is "easy"!!!

I have installed a few solar systems in RV's and assisted on a few others.  In virtually every case peoples needs evolved.  As they had power they thought of new uses for that power.  I suggest that people install at least a little more than needed and think about expanding in the future.  We have 1400ah @ 12v and use around 80% or more daily this time of year in the mountains heating with our mini split. Our 3,700 watts of solar need a clear sky all day to recharge.  Charging with the generator at 100amps our inverter/charger  takes forever.  That is probably extreme for most but you get the idea.

Watching the solar generate 200amps is impressive

Edited September 27, 2022 by Randyretired
Added solar output

[fpmtngal]

I’m envious of you and all that solar!!

And I’m a perfect example of someone who’s needs have evolved over time.  Which is why I think it is SO important to really think about what your needs are and where you think you might go in the future as far as power needs.

I was getting by very nicely with 370W on the roof, 120W portable with 300Ah of lithium batteries.  I wasn’t a big user of power - 30-50Ah a night seemed to be how much power I used, and while it’s short of the 2 to 1 ratio of watts to amps, it was enough to keep up with my limited power needs.

Then I bought Starlink a couple of weeks ago and am currently testing it out.  I also just signed up for Fubo for live TV, so I’ve been watching TV, something I haven’t done before when I’ve been boondocking.  Now I’m using over 60Ah a night and it hasn’t been that cold.  It’s been partly cloudy and my solar isn’t keeping up.

So now I’m researching how to add another portable panel and the wiring I would need, which varies depending on what portable panel I get (there doesn’t seem to be a lot of consistency between manufacturers and even different lines between manufacturers.  I have no idea how best to approach it and whether I should be looking for more than another 100W.  My head is swimming.

Based on my experience, I wish I had originally “dreamed big” and put in a bigger system to begin with, rather than start with only enough solar to keep a single Group 29 battery charged.

[bruce t]

Isn't it great that we are all different with different needs and expectations? Our camper is almost 3 years old and we are yet to turn on the TV. Actually we haven't even connected it yet. At night we read or listen to music. We never use a heater or a/c. We don't have it to use!! In almost 3 years we have only been in a campground and hooked up 2 times. It's called lifestyle choices. (We do shower so we don't smell. Well not much anyway!!!!). 😃

My point being is that our expectations are very low. We go camping to get away from civilization and it's gadgets. Others 'need' all the mod cons of modern society. That's fine. But what suits us may not suit others. And what suits others wont suit us. Just be realistic about expectations.

[VisaExpress]

This video will explain all about solar system.

[homelesshartshorns]

9 hours ago, fpmtngal said:

I’m envious of you and all that solar!!

And I’m a perfect example of someone who’s needs have evolved over time.  Which is why I think it is SO important to really think about what your needs are and where you think you might go in the future as far as power needs.

I was getting by very nicely with 370W on the roof, 120W portable with 300Ah of lithium batteries.  I wasn’t a big user of power - 30-50Ah a night seemed to be how much power I used, and while it’s short of the 2 to 1 ratio of watts to amps, it was enough to keep up with my limited power needs.

Then I bought Starlink a couple of weeks ago and am currently testing it out.  I also just signed up for Fubo for live TV, so I’ve been watching TV, something I haven’t done before when I’ve been boondocking.  Now I’m using over 60Ah a night and it hasn’t been that cold.  It’s been partly cloudy and my solar isn’t keeping up.

So now I’m researching how to add another portable panel and the wiring I would need, which varies depending on what portable panel I get (there doesn’t seem to be a lot of consistency between manufacturers and even different lines between manufacturers.  I have no idea how best to approach it and whether I should be looking for more than another 100W.  My head is swimming.

Based on my experience, I wish I had originally “dreamed big” and put in a bigger system to begin with, rather than start with only enough solar to keep a single Group 29 battery charged.

Thanks for your thoughts

[RV_]

Some great advice here.

Edited September 29, 2022 by RV_

[justRich]

This video from Will Prowse might help:

 

[homelesshartshorns]

8 hours ago, Rich&Sylvia said:

This video from Will Prowse might help:

 

Thanks

[homelesshartshorns]

Been reseaching! I understand that my Honda eu 1000 I puts out 8 amps? I also understand that a 100 watt solor pannel will put out 8 amps as well. So does this mean at full sun overhead they both will charge my batteries at the same rate?

[mptjelgin]

1 hour ago, homelesshartshorns said:

Been reseaching! I understand that my Honda eu 1000 I puts out 8 amps? I also understand that a 100 watt solor pannel will put out 8 amps as well. So does this mean at full sun overhead they both will charge my batteries at the same rate?

No!  The Honda is putting out 8 amps at 120 volts.  A 100 watt solar panel is putting out 8 amps at (approximately) 12 volts. 

So the Honda is putting out 10 times as much power (1000 watts) as the solar panel (100 watts). 

To compare apples-to-apples with regard to amps, you've also got to make certain that the voltage is the same. 

Edited October 10, 2022 by mptjelgin

[Vladimir]

3 hours ago, mptjelgin said:

No!  The Honda is putting out 8 amps at 120 volts.  A 100 watt solar panel is putting out 8 amps at (approximately) 12 volts. 

So the Honda is putting out 10 times as much power (1000 watts) as the solar panel (100 watts). 

To compare apples-to-apples with regard to amps, you've also got to make certain that the voltage is the same. 

That is correct, EXCEPT the battery charger accessory for the Honda only puts out 8 amps or so at 12 volts.

If you want to charge a battery get an 120 volt charger and plug it into the generator.

More on solar versus batteries here:

https://usbackroads.blogspot.com/2012/06/solar-or-generator-for-camping.html

I am now running 80 watts on the solar panel and also have a Jackery 300 battery for running my computers, phones,  IPAD and cell phone amplifier.

[mptjelgin]

Correct. I assumed that he would be using a battery charger or inverter/charger with the Honda. I don't know why anyone would use that anemic 12V output.

[Vladimir]

I bought it when I bought the generator, not knowing any better.  That is until I tried to charge a battery with it!!!

It is handy if your running your generator 24/7 to charge a battery on the side.  BUT I never would do that when a 100 watt panel would do the same.

 I figured you knew, but like me there are probably some folks out there that were surprised to find out the hard way.