1000 watt solar?

[maggie blair]

 Could you folks that Boondock help me out here? I have a 27 foot class C and the RV place here in Sacramento told me that 1000 W panel would be enough to run my RV. I have 2 6V deep cell batteries and they also said the batteries would be enough to run the solar panel. Solar is new to me so I would appreciate any and all information you might have to share. 

 Thanks so much, 

Maggie

[Carlos]

What does "run the RV" mean?  What items exactly do you expect to power?  Also, batteries don't run the solar panel, they are filled (recharged) by the solar system.

Batteries are like fuel tanks.  Their capacity and charge times are just simple math.  Let's go with a pair of typical GC2 golf cart batteries, which is a very popular upgrade.  Your rig probably has something different, but we don't know.  That pair of batteries has 225 amp-hours of capacity, so basically you can pull 1 amp for 225 hours, or 10 amps for 22.5 hours.  Basic math.  Then you just add up your loads, such as the lights, heater fan, and other accessories that you run often.  That will tell you how long you can run them.  Oh, also, you should only use about 50% of the capacity so you don't wear out the batteries very quickly.  So you really have an effective capacity of 112 amp-hours.

1000 watts at 12 volts is 83 amps.  That seems like a HUGE solar plant!  Do you have a link?  How much did they want?  My best guess is that this is a fake spec.  1000 watts could indeed do so much for you, but it would be a huge, expensive panel.  In ideal sun, panels make about 1.5 amps per square foot.  If true, then you could fully charge the 50% you used in less than two hours.

 

[SWharton]

Are you sure they said 1000w panel and not 100w panel? RV Solar Electric(Scottsdale,AZ) fand AM Solar(OR) for information. These are both reputable firms and won't rip you off or sell you what you don't need.  (I don't think a 1000 watt panel exists)

Also, what are you planning to do. Serious boondocking  or just once in a while. Do you have a generator? All this makes a difference as to what you get.

FYI-We have a 36' MH with a residential refrig and are comfortable with 600-700 watts.

[Carlos]

That would make more sense.  I've worked with 1k commercial panels, they aren't usable on an RV...

[maggie blair]

14 minutes ago, Carlos said:

What does "run the RV" mean?  What items exactly do you expect to power?  Also, batteries don't run the solar panel, they are filled (recharged) by the solar system.

Batteries are like fuel tanks.  Their capacity and charge times are just simple math.  Let's go with a pair of typical GC2 golf cart batteries, which is a very popular upgrade.  Your rig probably has something different, but we don't know.  That pair of batteries has 225 amp-hours of capacity, so basically you can pull 1 amp for 225 hours, or 10 amps for 22.5 hours.  Basic math.  Then you just add up your loads, such as the lights, heater fan, and other accessories that you run often.  That will tell you how long you can run them.  Oh, also, you should only use about 50% of the capacity so you don't wear out the batteries very quickly.  So you really have an effective capacity of 112 amp-hours.

1000 watts at 12 volts is 83 amps.  That seems like a HUGE solar plant!  Do you have a link?  How much did they want?  My best guess is that this is a fake spec.  1000 watts could indeed do so much for you, but it would be a huge, expensive panel.  In ideal sun, panels make about 1.5 amps per square foot.  If true, then you could fully charge the 50% you used in less than two hours.

 

Thanks so much for the info. I called the RV place back and she meant 100 watt. 

[maggie blair]

2 minutes ago, Carlos said:

That would make more sense.  I've worked with 1k commercial panels, they aren't usable on an RV...

I have a Lot to learn. Thanks for your help. 

[maggie blair]

15 minutes ago, SWharton said:

Are you sure they said 1000w panel and not 100w panel? RV Solar Electric(Scottsdale,AZ) fand AM Solar(OR) for information. These are both reputable firms and won't rip you off or sell you what you don't need.  (I don't think a 1000 watt panel exists)

Also, what are you planning to do. Serious boondocking  or just once in a while. Do you have a generator? All this makes a difference as to what you get.

FYI-We have a 36' MH with a residential refrig and are comfortable with 600-700 watts.

You are correct. She meant 100w. 

I do have a generator and would use it occasionally but most of the boondockers seem to frown on Generator use so I need to stay on their good side. 😊

I would like to run my heater or fans and lights without any worries. 

[Carlos]

Is it a quiet generator, or one of those open construction types?  That will make a huge difference in acceptance.

So go back to my math above.  A 100w panel will give you about 8 amps during full production.  This means no clouds, not angled away from the sun.  So it's just math on how many hours of production you get versus how much you use in a day.  For example, all of our LED overhead lights together use 2.4 amps.  That means that the amount used for running those for three hours could be replaced by one hour of sun.

There's absolutely no way to answer your question with a yes/no.  Everyone manages power differently, and has different devices (are your lights LED?).  My wife and I use little power, our friend with three kids uses a lot of power.

Also, it's obvious to some, but dealers are notoriously liars...none of this allows running your air conditioner or other 120v appliances.

 

[SWharton]

You also need to be careful not to draw your batteries down too low, a good monitor is worth the $$. Too low depends on the type of battery you have, wet cell or AGM. Continue to educate yourself about solar for the RV, come back and ask all the questions you want and once you know what you really want to power give AM Solar and RV Solar Electric a call and talk to them. Just more of your education.

[Carlos]

Yeah, monitors are dirt cheap now, and the installation isn't very hard.  I'll be doing a mini article/how to on a couple of low-cost monitors shortly, as I finish up the install and photos.  Meanwhile, here's what I'm using, and it works great...

 

https://smile.amazon.com/gp/product/B07D31K454/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

[mptjelgin]

43 minutes ago, maggie blair said:

You are correct. She meant 100w. 

I do have a generator and would use it occasionally but most of the boondockers seem to frown on Generator use so I need to stay on their good side. 😊

I would like to run my heater or fans and lights without any worries. 

To give you some perspective, a  single 100W solar panel is a minimal system. While it might work if you sparingly use a few lights and fans, it won't keep up with a lot more than that. Note that many common conditions will reduce overall output including cloudy weather, angle of the sun in winter (unless you tilt the panels), shadows, short day length (again winter), etc. We've got 520 watts on our trailer and a few cloudy days in a row really make a difference!

You mention your heater, and assuming that you are referring to a typical RV propane furnace they can be a significant draw. If you only run it now and then you may be ok, but prolonged use will quickly outpace what a 100W panel can restore. 

This can end up being a complex subject, but as noted above, step 1 is to do an "energy audit", which involves determining how many amps each appliance (lights, fans, furnace, fridge, etc.) uses, how much you plan to use them each day, and then totaling up your typical daily energy consumption. Only then can you determine how many panels/batteries you'll need. 

As noted above, drawing too much from your batteries will quickly kill them, so that is an expensive lesson that you should avoid. 

At this point you'll either need to educate yourself to the point that you can comfortably spec your own system, or rely on a company with a good reputation to work through the process with you. You got a couple of good recommendations above, but I'd be leery of a vendor that makes a blanket statement that a 100W panel should be enough to run your RV without asking a lot more questions.

[maggie blair]

3 hours ago, Carlos said:

Is it a quiet generator, or one of those open construction types?  That will make a huge difference in acceptance.

So go back to my math above.  A 100w panel will give you about 8 amps during full production.  This means no clouds, not angled away from the sun.  So it's just math on how many hours of production you get versus how much you use in a day.  For example, all of our LED overhead lights together use 2.4 amps.  That means that the amount used for running those for three hours could be replaced by one hour of sun.

There's absolutely no way to answer your question with a yes/no.  Everyone manages power differently, and has different devices (are your lights LED?).  My wife and I use little power, our friend with three kids uses a lot of power.

Also, it's obvious to some, but dealers are notoriously liars...none of this allows running your air conditioner or other 120v appliances.

 

This generator is a 4000 Onan built in to the side of the RV. It’s a bit noisy. Also, I’ve seen some solar panels that tilt. Is that important? 

I have a ton of research I need to do on this topic but I sure appreciate your information. 

Thanks so much,

Maggie

[Carlos]

The closer you get the panels to facing the sun, the more power they make.  I'm not sure by how much, though.  Also, will you want to get up there and tilt them to face the sun every time?  If the sun is low in the sky, and the panels are flat, they will produce much less than they do facing the sun.  If you're far North in the winter, you'll get very little from them unless you do tilt them.  And of course, dirt/buildup will reduce power, so they have to be cleaned.

 

[maggie blair]

32 minutes ago, Carlos said:

The closer you get the panels to facing the sun, the more power they make.  I'm not sure by how much, though.  Also, will you want to get up there and tilt them to face the sun every time?  If the sun is low in the sky, and the panels are flat, they will produce much less than they do facing the sun.  If you're far North in the winter, you'll get very little from them unless you do tilt them.  And of course, dirt/buildup will reduce power, so they have to be cleaned.

 

Great info and thanks again. You are very knowledgeable! 

[Carlos]

No problem, happy to help.  I've worked with electricity all my life.

 

[pjstough]

A good place to start to learn about solar.  The more you know about solar, the better the chances are that you get a good system that will meet your expectations.

http://www.jackdanmayer.com/rv_electrical_and_solar.htm

[jcussen]

5 hours ago, Carlos said:

That would make more sense.  I've worked with 1k commercial panels, they aren't usable on an RV...

Love to see a 1000 watt panel, do you have a link to any manufacturers?

[Carlos]

No, that's just what they told me was up there.  I was just working on a problem with the charge controllers.  Basically the panels were so cold, but AZ had so much sun, that the controllers couldn't bleed off the excess voltage.  It was causing the 48v gear to shut down for safety.  I put a household heater on a remote switch so it could be used to kill excess power.  Oh, and the site is SRP-sponsored, the panels could very well be experimental, who knows.

It would have sucked to cook off this many batteries!

[jcussen]

Thinking that with present technology, a 1000 watt panel would be well over 200 cells and well over 100 volts. A buddy that installs grid tie, says a panel that big would be like 10' by 8'. and size and voltage would not make it paractial. Biggest panel I have ever heard of is 420 watts with 60 volt VOC and is  over 6x4 ft, but they haven't been sold for a while.

 

[Carlos]

This grid is much larger than 10x8.  No idea how it's composed.  Look at the wires running to it, they're not exactly phone wire.

[maggie blair]

1 hour ago, Carlos said:

No problem, happy to help.  I've worked with electricity all my life.

 

People like me are fortunate to have people like you on this forum. 

[maggie blair]

7 minutes ago, jcussen said:

Thinking that with present technology, a 1000 watt panel would be well over 200 cells and well over 100 volts. A buddy that installs grid tie, says a panel that big would be like 10' by 8'. and size and voltage would not make it paractial. Biggest panel I have ever heard of is 420 watts with 60 volt VOC and is  over 6x4 ft, but they haven't been sold for a while.

 

It is a 100w . I misunderstood the lady at the RV place. Sorry

[maggie blair]

1 hour ago, pjstough said:

A good place to start to learn about solar.  The more you know about solar, the better the chances are that you get a good system that will meet your expectations.

http://www.jackdanmayer.com/rv_electrical_and_solar.htm

Thank you so much.

[jcussen]

9 minutes ago, Carlos said:

This grid is much larger than 10x8.  No idea how it's composed.  Look at the wires running to it, they're not exactly phone wire.

Most grids are multiple panel, so imagine much, much bigger than 10x8.. Just can not understand the 48 volts? Most big arrays are panels in series to up to 600 volts.

 

 

 

[Carlos]

48v is what the telecom equipment requires.  The panel inputs come into a bank of controllers which need to output 48v, and I think the input is around 55v nominal, but that day it was well over 60.  Which the controllers couldn't dump, and that's why we had to jump on a helicopter.  The site is at the top of Estrella mountain and serves a bunch of companies, SRP, public safety (DPS), radio trunking systems, ISPs, etc.