Solar Myth

[JDCrow]

Since getting into RV years ago, we’ve all watched as solar is gaining traction in us more self sufficient when off grid. 
 

I was convinced at some point that one would be able to really live how they wanted with solar. When I first came on here I was kinda mystified at how many use their gensets, daily. I knew solar was spendy, so that was my rational. 
 

I’ve been following a start up couple on YouTube, and I think they were kinda duped like myself at the power of solar. 
 

Here is the link of their install, and then a video of their first month in Quartzite when the truth about their solar power kicks in. 
 

Any thoughts?

 

 

 

[vito.a]

I agree with you to a point.  Most folks confuse watts with amps and do not understand how small the solar output is.  

[JDCrow]

1 minute ago, vito.a said:

I agree with you to a point.  Most folks confuse watts with amps and do not understand how small the solar output is.  

In their last video, they talked about getting 1 hour of tv or 1 hour of computer. Who wants that? They said they need to buy new tvs/computers/refer that consumes less watts.

So if the double their current set up, 2400 watts do they get 2 hours of TV a night? I know it’s not that simple. But wow what you pay for solar you’d think it would be a bit less mystifying 

Someone needs to kick out a simple, laminated sheet with cost, hours, weight, etc so I can get simple fast. 

 

[Rocketman3]

I kinda don’t get how people get don’t get solar…. I think most people don’t do the math behind their system and don’t understand their real usage. (That is the real reason).
 

On my 2000 Dynasty, when I bought the rig the inverter was dying, so I replaced it with a Victron Multiplus 12/3000. I also added 800watts of solar and new lead-acid batteries. That worked great! I run the microwave off the batteries  (lunch as long as needed - dinner less than 5 min).

A few years later, added a residential fridge and 400 more watts of solar and a 540ah lithium battery (self made) and went full time. (Now no limit on microwave- I also use the convention baking in the microwave- plus instpot & toaster - but just one high use item at a time. 
 

in January in Arizona if I don’t tilt the panels I need to run the generator every three days for an hour. Once I tilted one set - that gave us enough to not run the generator- unless cloudy all day. Tilting adds a lot of extra power. Currently I only tilt one of the three sets of panels. (Getting the other two to be able to tilt is a project on my to- do list).
 

The residential fridge uses a lot of power, but the solar fills the batteries. Last night(mid-March) in AZ, the solar is basically over by 5pm. We fixed dinner (leftovers - microwaved) my wife was on her computer until late and I read my book (lights on) until midnight. The rig uses 20% of the batteries at night (electric blanket, fridge, etc), so I woke up with my battery somewhere around 65% (didn’t look this morning).  At 10:40am it is now at 73% and the solar is producing 750watts - with 525 going into the batteries. I will be back to 100% by 2 or 3pm. 
 

We can handle one cloudy day - if we get two in a row (in the winter) - the generator needed ran anyway. If just partly cloudy- three days until the generator needs to be ran. 

Edited March 9, 2022 by Rocketman3

[JDCrow]

38 minutes ago, Rocketman3 said:

I kinda don’t get how people get don’t get solar…. I think most people don’t do the math behind their system and don’t understand their real usage. (That is the real reason).
 

On my 2000 Dynasty, when I bought the rig the inverter was dying, so I replaced it with a Victron Multiplus 12/3000. I also added 800watts of solar and new lead-acid batteries. That worked great! I run the microwave off the batteries  (lunch as long as needed - dinner less than 5 min).

A few years later, added a residential fridge and 400 more watts of solar and a 540ah lithium battery (self made) and went full time. (Now no limit on microwave- I also use the convention baking in the microwave- plus instpot & toaster - but just one high use item at a time. 
 

in January in Arizona if I don’t tilt the panels I need to run the generator every three days for an hour. Once I tilted one set - that gave us enough to not run the generator- unless cloudy all day. Tilting adds a lot of extra power. Currently I only tilt one of the three sets of panels. (Getting the other two to be able to tilt is a project on my to- do list).
 

The residential fridge uses a lot of power, but the solar fills the batteries. Last night(mid-March) in AZ, the solar is basically over by 5pm. We fixed dinner (leftovers - microwaved) my wife was on her computer until late and I read my book (lights on) until midnight. The rig uses 20% of the batteries at night (electric blanket, fridge, etc), so I woke up with my battery somewhere around 65% (didn’t look this morning).  At 10:40am it is now at 73% and the solar is producing 750watts - with 525 going into the batteries. I will be back to 100% by 2 or 3pm. 
 

We can handle one cloudy day - if we get two in a row (in the winter) - the generator needed ran anyway. If just partly cloudy- three days until the generator needs to be ran. 

This is kinda my point. 
 

I believe solar is being marketed as a replacement for gensets and plug in power. It just isn’t. 

[jacwjames]

I spent too many years working where we had to justify anything we purchased by doing a cost benefit analysis.  After doing that for 35 years it becomes second nature and to this day I run a CBA in my head on just about anything I buy.

Trying to justify adding sufficient solar that would reduce (but not eliminate) the generator usage is difficult, especially if you don't full time.  At one point I was contemplating adding solar and just could not get the math to work out.  One contributing factor is that my wife travels with dogs and if it is the least bit hot & sunny the generator comes on to be able to run the AC. 

I did the exerciser again when we installed a residential refrigerator and still couldn't see adding solar to offset the additional usage versus just running the generator for ~1-2 hours a day.  I do have 325 watt of solar and on a trip this summer it did pretty well keeping up with my demand, I would still have to run the generator some even on cool days and if it was hot the genny would run anyway.  

So for me I just can't justify the cost. 

 

[Bob Jones]

There's something wrong with those guys or their setup. I did a solar install on my parent's new unit, two large residential panels, I believe 900 watts total, it makes 50 amps DC in direct sunlight......up here in Canada.....

It only has two trojan T105 batteries and we left the fridge on 24x7 in the summer for.....more than a month with nothing in it set to full cold. Any modern flat screen Samsung uses about 40 watts max. Point is, the fridge never ran out of power, even through the night (batteries by night, solar by day). 

With the Victron app you can readily see whether you have a net surplus of solar while operating your equipment. We were never able to get it to draw more power than the sun was making. BUT we do not yet have an inverter so no TV and no Microwave. But here's the thing, The TV's are new. They draw nothing. I would expect them to draw 20 watts each (x3 = 60 watts) if you were watching all 3. That leaves the microwave and loads such as a kettle or coffee maker. 

Kettle or coffee maker are short time loads. I would not expect any issue with them based on duration of use. The Microwave though is a bit tougher. It's a larger load that, ideally, should be able to run for 30 minutes or in a perfect world, 60. In my motorhome (2000 Diplomat) it's no issue with 4 Trojan T105's with no incoming power at all to replenish the batteries as I have no solar. I would expect, in their case, that we would need to add two more batteries for making a meal with the microwave. 

There's something wrong with their install, their design, or their consumables in their unit. They also talk too much and say nothing. It's very easy, with the Victron app on your phone, to just shut everything off in direct sunlight and then walk around turning everything on, one by one, and seeing whether you are in a net gain or net loss situation. This also makes it very easy to see what the power pigs are. 

I'm not a global warming fool, I don't have an electric car, and this was my first solar install, and I was sceptical. But the fact is, the second we turned it on, it started cranking out power. I couldn't believe it since I had never seen a solar install work before. Didn't know anyone that has one....

But I know how well it works up here, and it's much more sunny down there....so...what's the difference? We don't yet have an inverter so we are minus the TV's and the microwave. But I already know how they will work based on my 20 year old 1500 watt Trace inverter and 4 Trojans in my unit. 

The only issue I can see in my parents setup, once we invert it, is not running AC. That is asking too much of it. Those folks need to spend less time making videos and more time walking around with a kill-o-watt to see where they are leaking power. 

Btw, there is enough room left on my parents roof (29 foot unit) to add in probably two more half-panels. Bottom line, we could not use enough power to overcome the sun during daylight hours no matter what we did. That will change a bit with the inverter,  but not much. Not much at all. Last thing. It's beyond me that people cannot understand that a properly chosen residential fridge uses MUCH less power than, let's say, my Norcold 1200 LRIM. A quick check with my Kill-O-Watt, or even reading the label on the fridge, shows it uses 500 watts. When you extrapolate that out to a month it adds about $30 (!!) to my Hydro Bill, if not more. The go look at the energy label on a new modern fridge of roughly the same size. It will show you that it uses less power in one full year, than the Norcold uses in one month. Should it not be obvious to everyone at that point that if you are on solar it's going to be a cakewalk with a modern residential fridge?

 

 

 

Edited March 11, 2022 by Bob Jones

[trailmug]

Battery technology can't come anywhere near the power density of a diesel tank, plus recharge can be had immediately for $$.

Best we do with two panels on our rig is break even with the daytime standby loads. It'd work as a battery tender (salesman switch open), but it would take a lot of determination and some good luck (weather) to live off of what you can fit on the roof.

Edited March 9, 2022 by trailmug

[Rick A]

I just bought the whole diesel thing. My solar is just another irritating over expenditure and I just shut up about it. 

[Ivylog]

I knew going in my 1000W of solar ($1200) would never pay for it self as we only dry camp for 40-50 days during the summer. Parking in the shade doesn’t help the solar but makes AC unnecessary…more important. I did solar because I got a really good deal ($0.50/watt) on panels that were the right size for where I was mounting them.
IF you spend the winter where you need some heat, not AC (currently running the AC) parked in the sun getting lots of solar might have a payback if you DIY it.

The best $200 you can spend is on an additional 100A battery charger if you dry camp a fair amount. Even then I still have to run my generator 1+ hours/day… whenever I’m going to use a high amp appliance.

[Rocketman3]

I just watched most of the three linked videos above - let me give you my opinions (as a full time boondocker in a Class A with much the same equipment). I happened to be in Quartsite this winter too. But I didn’t need to run the generator. 
 

I have 1200 watts of solar (same as they have) and that might be enough for them, however here are the differences: they installed two Multiplus 3000’s. I only have one - but that’s another 30watts 24/7 - which will mean they should have one more 200watt panel to cover that load. 
 

The one video shot I noticed from overhead showed flat panels. When I tilted two of my panels I got 100 more watts. It’s winter here with the sun low - panels need to be tilted or you need a couple more. 
 

Batteries - they said they installed four Lion batteries - I believe those are 100ah batteries. My batteries are 540ah (or so) of lithium. One or two more batteries would help them a lot.  
 

To me it looks like they did not do all the math at the beginning of the project for winter solar. Now as they get into summer and the sun is up more they will probably be fine. If they park their rig in the proper direction and tilt their panels- they may have enough to get by in the winter. (But one or two more panels and batteries would really make it go from watching everything constantly to only watching on low solar days).

Just my opinion-  but I like to run my rig so I don’t have to constantly think about power. It is also really nice not to hear the generator running. 

[Tom Wallis]

I have considered solar several times over the years but every time I do I decide the cost out ways the benefit. Mind you we're not big time boondockers.  It's usually just for a few days now and then.

No one in this thread has really addressed the cost. There's the panels of course, the solar charger and most have lithium batteries which might mean 1 or 2 new chargers. That's a lot of money. As much as I would like to have lithium batteries, and I fully understand all the advantages, I can't really justify that cost. My 4 year old 6v batteries are still in perfect condition.

However, in recent years my electrical demand has increased considerably.  My wife has COPD and we run the inverter and an oxygen concentrator all night. If we go to bed with full batteries we're at 50% in the morning. It take a lots of generator hours to top off FLA batteries.

For me the most cost effective solution is a 2000 watt, 38 pound, 53 db generator for less than $500 that runs all night on 1 gallon of gas. And if I can't run it all night I can run it most of the day. No it might not be quite as convenient or work in all situation but it's really quiet and cost effective and works out great for us. And we still have the big generator for AC.

 

[Bob Jones]

Ours, pictured above, was $700 CAD for the two panels and about $500 CAD for the solar charger. Add in $200 CAD for miscellaneous and there you go. $1,400 CAD = $1,100 USD for 50 amps DC. 

We opted for two new Trojan 105's and an optional battery meter and some switches so that was extra but did not have to be done. Our original goal was only to keep the coach batteries charged when stored. When we looked at the cost of buying a setup like that from an RV place it was a no-brainer to upgrade to residential. Up here they were selling RV solar kits for $800. I  think they made 200 watts. We went to 900 watts for roughly twice the price with top-end Victron gear and panels. The $800 from the RV store got you cheap Chinese junk. We've got best of breed, quadrupled the output and have an app on our cell phones to monitor the solar charger and the battery meter. 

50 Amps DC when the sun is shining...up in Canada, no less. We couldn't be more happy and cannot use more than it generates during the day. We tried. Mind you, no inverter yet and so no Microwave but I don't see any issue with it if we go that route. We just have to live without AC. 

Best of all, it's 100% seamless. My parents don't have to do anything. It's all automatic and there is one disconnect switch to turn it off in case of servicing etc. We can easily add two half-panels to the roof with minimal effort just by tapping into the existing wires and upgrading the controller to handle the increased output. So there may well be another 500 watts within easy reach bringing us up to 1,400...

But the thing is this. When we did it, we made it so it could be done in stages, because, to be honest, I didn't think it work anywhere near as well as it does. I was a skeptic. So we looked at it this way, the RV crap was $800, ours, in the end, with new batteries etc was roughly $2,000 - so we 'risked' $1,200 for a way, way, way better system. Top of the line. And we did it more/less on a lark. I did the math on it, so I knew what it should do in theory, but we didn't really believe it. When we turned it on after it was installed, in the late afternoon, it put out 42 amps. We were shocked. 

We then left the fridge on, empty, set to full cold, for more than a month. Looking at the app, overnight, the batteries never got anywhere near depleted. As soon as the sun came up the next morning, they were full in no time. During the day we could never use more than was being generated. 

What I'm saying is, if a guy wanted to dip his toes into solar, in stages, incrementally, so that you can see for yourself, it's easily doable in that fashion. And it can be built-out and expanded quite easily with minimal $$ loss. Just mind the Air Conditioning, if you have to have it where you're at, it changes everything. 

The big hit for us, since our new unit did not come with one, would be the inverter. If we do it, I want to do it right. The Multiplus 30/50 inverter, the color touch screen, network wiring to all the devices, central control etc. Up here I budgeted $6,000 CAD for that (parts only, we do the install). That's the big hit. But, I'm reasonably certain that Dad could pull into a park and not bother to even hook up to the pedestal after that. Bearing in mind, they are not full-timers, they are weekend excursions during the summer. So in our case, ~ $2,000 for the initial solar install, add in $6,000 for super deluxe inverter install, total, $8,000 CAD ($6,200 USD). That's doing it yourself but that's also the absolute living end on the inverter side. Every option. Highest quality cabling, you name it, it's in it along with a decent fudge factor for bits and pieces. 

 

 

[seadoo200hp]

 have considered solar several times over the years but every time I do I decide the cost out ways the benefit. Mind you we're not big time boondockers.  It's usually just for a few days now and then.

No one in this thread has really addressed the cost.

 

No one has addressed the weight of the panels either, at least not in this thread.  

 

[Bob Jones]

On ours the weight of the panels pictured is about 45 pounds each (90 total). So the weight is completely irrelevant when you take into account the area it is spread over. 

[Rocketman3]

I will address the cost:  (about 1230 watt system).

If you have a lot of room you can get used 250watt panels for like $60 each from Suntan solar in Az. I wish I could have used 5 of those but they were too big for my roof. (Too many A/C’s, fans, vents, fridge, satellite, etc). They are nice panels- I put two of them on my Dad’s 5th wheel.

For my 36’ Dynasty, I chose 200watt panels from continuous resources.com (this is also my Victron dealer) when I put my first four on they were $200 each (shipped to me). Now you can get them for $185. When I added my fridge - I added two more 215watt panels for $200. This size fits well.  I have heard you can find 200watt panels on sales at Home Depot for like $150.

For the SCC (Solar charge controller) I chose Victron- which is a premium controller. You can find cheaper ones ones. I really like the addition info I get from the Victron’s.  My first four panels are connected to  Victron Smart mppt 100/50 in a 2s2p arraignment  My other two panels are on a Victron Smart mppt 100/30 in a 2s arraignment  Their prices are $323 and $226.

Self-made brackets -probably $250 for brackets and wire and breakers.

So yes my system was expensive 

panels $1200

SCC-Mppt. $550

other $250

Now there is also a Federal US tax credit for solar systems and their related equipment (batteries are included if installed with the solar). I forget the actual credit - I think it is 26% or 24% (it was 30%). 
So my $2000 cost dropped a lot - because I also installed batteries. (It would have been $600off just for the solar).  If you are installing batteries- look at doing a solar system then.

so yes an expensive system - but it worth it to me.

(The used panels do not qualify for the solar credit - but if you have the room, you can find 330w new panels for great prices!)

You can also do it in stages - like I did.

This Weight doesn’t matter on my Monaco roof. 

[Rocketman3]

On 3/9/2022 at 11:33 AM, JDCrow said:

This is kinda my point. 
 

I believe solar is being marketed as a replacement for gensets and plug in power. It just isn’t. 

It can be - at least for the big generators. 
 

If my 7500w Onan were to completely die (repair not an option) - would I replace it - nope!

I would pull it out - put a 48v 10000w inverter in (that would power both A/C’s) and a large lithium battery (my current guess 48v 560ah battery (26kw battery) - I would need to do the math - this is a guess). Add a few more solar panels.  That battery alone would give me 2-3 days of A/C at someplace hot. 
 

It would be slightly cheaper than a new generator. If I needed I could always get a LP “Honda” 2000w generator (hook it up to my propane tank on my rig) but I don’t think I would need it.  

Now is this a system that I could spend a time somewhere hot (Texas summer) boondocking? - a few days - sure. Then hit a RV park for a day or two - then repeat. The only difference is my friend in a regular MotorHome- would be running his generator the whole time we were out.