KC8QVO well thought out posts.

As a fulltime boondocker living within in your power wants is easy enough. Been doing it with 1,280w of solar 500ah of LFP (5,120Wh usable) as posted in my National Forest thread for the past 4+ years. If the need for the air conditioner is required the eu2200i generator will handle the 15k unit but prefer to move to a cooler location if possible. I like the quiet while boondocking personally, "having your cake and eating too".
I'll agree that for some it's probably easier to just go to the rv park plug in the cord and start turning all the luxury items on just like in your stick and brick home.

 

Can you detail your use-case?

I have a couple portable AC's that run on my 2200w Honda (not at the same time, but the EU2200i has the capacity to run them). Good, impressive generators.

If you keep the AC on then you need to keep the generator on. What does that do to fuel consumption? Do you run an external tank (with a fuel cap adapter of some kind - not sure if you have a Honda, but I know they exist for Hondas as I bought one - a knock-off from Ebay, but it works)?

Then the question that comes to mind is how much fuel do you carry?

It is one thing to be in a somewhat mild climate where when it gets to the afternoon sun you kick on the AC for a couple hours, then turn it off. When you want that controlled climate around the clock the consumption goes up dramatically. And that is reflected in the 13 gallons of gas/24hrs and 38kwh/24hrs figures in my earlier example.

I agree with the solar set up you have. When you don't draw much power it is rather simple to provide all of that which you need from solar panels - and sizeable sets that you can work with them easy enough transporting and setting up (yeah, it still takes some work - but compare that to trying to set up an array of 68 full size 200w panels in my earlier example!). The difference is the deep energy usage of the AC's, namely.

Heating (or the opposite - cooling) is what naturally will use more energy because you are combating energy on two fronts -
1. Environmental change. The environment will set your temperature at one value. Think heat in the summer in the sun. Left alone it would be 175 degrees in your RV. The temperature change takes energy to shift that temperature to a more comfortable temp.

EDIT: Illustration - I need to check the conversion values - I am second-guessing the 15kBTU/hr = 4kw factor below. So don't take the numbers literally, just the idea of:
2. Energy conversion. 15,000BTU's per hour equates to roughly 4,000w. If you have 15k BTU of AC ability your AC's are going to pull more than 4,000 watts because you have to convert electricity to cooling through the AC compressor and motor - the Energy Conversion. That takes energy.

Edit: I do see you listed your AC as "15k" also. I assume that is 15,000btu. If the 4kw value was correct you wouldn't be running that on a 2200w generator - even with a 2800w starting rating on the generator.

In the AC example - just the temperature conversion alone takes power - 4,000w for 15k BTU. If there is that much energy to shift the environmental temp the percentage possible to trim input energy is comparatively very small. Even if motors and compressors were 100% efficient (no energy loss) you still have 4000w of power to provide to get 15k BTU.

That's something to think about also...

And go back to my 2nd edit under the usage chart - we're under 20kwh with 5 buildings for 24 hours (there are peaks higher than that, but that is a base-line sustainable energy level). Granted, no AC in those figures - but that includes a well pump and water heater (5kwh is the water heater alone). What we're not doing is shifting the environmental temp = huge amounts of energy as all the numbers show.

 

Yes, Just recently I added the Micro-Air Easy Start 364 (ASY-364-X20-IP) to the Carrier Air V 15k air conditioning unit (low profile).
From my other thread on the installation of the easy start. https://www.ford-trucks.com/forums/1...l#post19310389
I can run it off of the EU2200i and not only that I have run it off of just the solar/ batteries, granted if it's run like this long enough the generator will need to charge the batteries but for short term use of a lunch stop or just an hour or two to cool things down some no big deal. As I said if it's going to be "HOT" it's time to move anyways.

I only carry 2 gallons of gas.

I have a Magnum Hybrid 3,000w inverter/ charger unit so I can adjust the incoming current and load share it with the solar.

From that thread...I'm in a campground hooked up to 50a service, completed the 5 learning cycles. It was interesting to watch the Magnum Me-arc display in the ac input screen, the air conditioner fan would run for a couple minutes then I could see 3-4a load coming in for 60 +/- seconds then quickly climb to roughly 18-20a then settle at 14a.

Looking at the service manual the locked rotor amps for the low profile high capacity is 59.0a now best I can tell since the easy start install it appears to be 18-20a.
While still plugged into the pedestal I turned the load share down 15a, 10a, 5a and turning the air conditioner off for a couple minutes between each lowering and at no time did the ac unit stumble or did a red fault light show on the me-arc.
Then I disconnected the the power from the pedestal and connected it to the eu2200i generator setting the ac input load support to 15a and 10a, same results no red fault light on the me-arc and no "overload" or stumble on the generator. Also I'm in tree cover/ overcast so little to no solar was helping.

Tried the 15k A/C unit from just batteries with hardly any solar contributing to see if the fault light would show on the Me-Arc display from the hybrid inverter, no fault light and no stumble in the A/C at anytime.

99% SOC (13.3v before turning the A/C on)

From the me-arc display:
Inverter AC output 118v/ 60hz

Overcast/ pine forest (no visible sun)
Solar 180.7 watts
PV volts 35.7vdc
Batteries 13.1vdc (while A/C running)
8a charging from solar after turning A/C off

Initially turning it on the fan started and after 30 seconds the compressor started to spool up slowly, I could see the amps slowly climbing and max somewhere in the 190a + range before settling down to 94a. So if I just use my minimum loads and the sun is shinning the solar panels will cover roughly 60-75a of the A/C load, balance from batteries would be 30ah +/- (6% SoC be depleted per hour).

Just my hands on experience.

 

Reversing the above thought.. another deep thought, I know:
That also reads that the environment in and of itself can provide a lot of energy. The question, then, becomes how to harness it. Not specifically speaking to a change in temp being able to be harnessed - just the idea of what is already around us being able to provide energy if we can shift the form (or convert between). IE - solar, wind... Crazy, I know, right? Then the pipe dream is to get 50 amp electric service from a tow vehicle. The irony is how much energy is already all around us all the time. It's just in a form we can't use because we can't plug in our RV's, boats, homes, what have you's in to it.

 

Thanks for the input. I am just getting around to digesting your numbers

From the specs on the Magnum Hybrid 3kw inverter/charger (if I am looking at the right unit, link here) it can supply a max of 3500 watts. That equates to a hair over 29 amps at 120v. That would make sense with your Easy Start current being 18-20 amps - you still have head room in that 29 amps, so your info makes sense that you aren't overloading it.

The 2800w starting ability of the EU2200i puts the current at 23.3 amps. Though you are closer to that, you're still a bit under.

My well pump runs on the EU2200i - I am not sure how much current it pulls (at start up), but oddly enough between the EU2200i and the supposed "2600 watt" open frame generator I have the little EU2200i starts the pump motor the easiest. Go figure that one.

I will dig in to the rest of the numbers (solar) in a bit. Something seems odd to me about it, but I haven't put my finger on it. What I can say is current at one point in time (full sun on the panels) is different than energy - watt-hours or kilowatt-hours over time.

 

That is the correct Magnum unit.

"What I can say is current at one point in time (full sun on the panels) is different than energy - watt-hours or kilowatt-hours over time."
Yes it is, but without one you can't have the other.

As far as solar production or kWh harvested most I've seen on my system 7.4 kWh in a day but then there are only so many things to turn on in the 5th wheel, plus it's a small system.
3.5 - 4.5 kWh is the norm for the usual everyday items, if I turn the fridge over to electric then 6 - 7 kWh is the norm. These are just averages from the past 4+ years living off of the solar/ lfp system.

 

Here is what I see when I look at your numbers.

A couple of things:
1. For those that aren't quite up on terminology - SOC is "State of Charge". That is the battery bank capacity. What I don't know is the depth of what that rating is as used in the use case. My reason for that unknown is that different battery chemistries have different useful depths of discharge. For example - lithium batteries can be taken down to 30% or so without too much damage, whereas lead-variants (sealed lead acid, flooded, AGM, etc) you are at 80% (that might sound ridiculous but that is the best way to try to keep your batteries "healthy" if you have leads).

2, There are two different usable values for battery capacity. Those are:

A - Amp Hours. You can roughly equate this to watt-hours, or kwh, by using a nominal voltage. However, as the SOC changes so, too, does the voltage (lithium batteries hold a higher voltage, even under load, than any lead battery, for example). This means that your watt-hour conversion is not going to be simple math. Then you have to take in to account my point about the 20% vs 70% usable capacity of the battery to add to the complexity in the calculation. On-label capacity is only truly useful for giving a comparison to battery sizes, not what you can actually get from them (without doing math and putting your own numbers in - what DoD do you want to take them to? If you go high on the DoD you set yourself up for disappointment).

B - C, or Discharge Rate, or ability to deliver current (current is power). A battery that is, we'll call it, a 100 Amp-Hour battery that has a discharge rate of 1C means you can pull 100 amps (1 times the capacity rating, in Ah). A battery that has a 10C rating, with a label capacity of 100 Amp-Hours, in comparison, has a 1,000 amp discharge rate. Note that the same 100Ah theoretical label capacity is here - yet you get the ability to draw 10x more current. It just won't last long doing so.

Here is a neat video that shows discharge current in action - melting a wrench.

My point - batteries can supply tremendous amounts of power, but energy - the ability to provide power over time - is a totally different matter.

So that said:
So your solar power production at the point in time you measured it was 180.7 watts. The voltage was 35.7.

There are some quotes here from your other thread as the information is relevant here:


So the Magnum is also a solar charge controller (as opposed to one that runs on AC as in an AC-coupled system). If you look at the specs of the inverter/charger it is stated as being 86% efficient (the charger efficiency, the inverter efficiency is 88% - two different numbers).

There is another factor that I assume is wrapped up in that 86% - that is MPPT - maximum power point tracking. The theory is that a "charge controller" will sample the solar production and find the point on a power curve where the production is the highest.

If you divide out watts to volts and amps you get a straight line. However, solar arrays don't work that way - there is a point where, in any given amount of sunlight, the panels are most efficient. If you load them with too much current the wattage actually drops and you leave rather significant amounts of energy on the table when every tidbit you can harness might mean something. The weaker your production (cloudy days, for example) the larger this problem becomes. That is why MPPT is so important.

So lets look at that 86% charge efficiency of the Magnum again - I assume, I can't find anything in the manual that spells it out, but I assume that 86% efficiency is MPPT. The reason I am assuming that is if they are not using MPPT they can't spec 86% with any reasonable accuracy - it will be all over the board. So I am still skeptical of their 86%, even still, but assuming they use MPPT I am at least less skeptical.

So we'll take that value as a starting point and say that the charge current from your solar panels making to the battery is:
(180.7 watts out of the panel / 13.1 volts of the battery) X .86 = 11.9 amps

That 11.9 amps, over the course of 1 hour, translates in to roughly (negating the voltage changes by using 13.1v as the nominal voltage) 155.9 watt-hours. If you get that amount of production for 4 hours a day (it will vary, so this is just an illustration) - that will be (4 x 155.9) = 623.56 watt-hours, or divide that by 1000 and you get .62356kwh.

Here is another quote from your other thread detailing the batteries:
I am going to come back to the bold details below because this changes up the production numbers significantly from your earlier 180.7 watts.

I am assuming that is 500Ah TOTAL (I didn't see a quantity of 500Ah batteries, just the 500Ah total), lithiums to boot - cool beaners. So, at a 70% DoD you should have about [(500a x 13.1v)*.7]/1000 = 4.585kwh usable if drawing from solely the batteries, and you are not drawing a very large C value (discharge rate). Of course, when you throw in solar in the mix your production is going to compensate for some, most, all, or more than the draw - and that is where tracking energy production vs energy consumption will paint the real picture here. The rules of the situation are that if your production is less than consumption you will drain the battery; If your production is greater than your consumption you will charge the battery.

Lets look at that C value:

You saw current draws (on the 12v system side) of 190 amps or more.

Your label capacity of the battery bank is 500Ah so doing the math that comes out to (190 / 500) = .38C - a hair higher than 1/3C. That is pretty small.

Think about that for a second - your current draw on the DC side is 190 amps on the high side, and going back to the whole slew of posts above I've spelled out how energy-hungry AC units are, yet when you lay out the numbers your discharge rate is a measly 1/3C.

Your ability to deliver power (wattage, amps x volts) is far, far, far greater than your ability to sustain energy over time. I hope that sinks in for anyone else reading this thread.

Revisiting the point on the 1280 watts vs the 180.7 - there is some mud there as to what you are really dealing with. However, for sake of running numbers we'll use the high side - the 1280 watts. I assume that is label wattage, and no factor for less-than-peak-conditions. Either way, we'll use it as a point of illustration:

Using the same 86% efficiency in the Magnum charging circuit as earlier, along with the 13.1 volts, that gives us:
[(1280 watts / 13.1 volts) x .86] = 84 amps.

1280 watts x .86 (charge efficiency) = 1100.8 watts. For a 1 hour period that is 1100.8wh, or a 4 hour period that is 4.4032kwh. That is some respectable power.

And yes -
if you have 4+kwh available from solar, the ability to store 4.585kwh, and the ability to provide your 190a peak current draw from the AC at only 1/3C of the battery bank then you can run your AC - for a period of time - off nothing but the batteries.

And if you can pump 4kwh+ from solar in to your electrical system at the time your AC is running you will slow down the C on the battery. Depending on what the duty cycle is on the AC running you might be able to float the electrical system (IE - leave the battery nearly charged at the end of the day when the sun goes down, not less charged than when you started for the day).


What was odd was that your 180.7 watts from your "panels" didn't make sense. The 1280 watts buried in your other thread is a lot closer to what you are really dealing with.

Good stuff.

 

Ah yes. The "edit" button. I looked back and you had more info.

Interesting - my 4kwh production from my numbers hit right smack in the middle of your 3.5-4.5 normal range of consumption (minus fridge).

 

With my earlier math that comes out to about 4kwh during the +/- 2 hour range (4 hours total) around peak solar production time in a day.

So if you throw the fridge in the mix and we look at the higher number - 7kwh - that means to keep up with that energy over time you would need to add 6 more panels.

I assume those averages do not include much, if any, AC use. So that 14 panel set up (original 8 plus additional 6) doesn't net you the ability to run the refrigerator and the AC sustainably.

I realize your earlier comment:
I'm just laying out the numbers for clarity's sake for anyone else reading through.

And the last point for now -
Those 8 panels that you already have (and the intricacy in the system you built - inverter/charger, batteries, the whole 9 yards) are your realization to being able to "plug in" your RV in to one form (solar) of energy that is around you.

 

This bothered me - what I got with the math came out to 11.9 amps, 2.9 amps more than what you showed. That 11.9 amps is calculated from the provided panel wattage at the time (as noted - on a cloudy day), not the charge current that was listed. See below. Also note my assumption on the MPPT function in the 86% efficiency of the charging:

What I failed to note in the other thread detail was this:

Bold added.

That is a separate device, not part of the inverter/charger. It also happens to be an MPPT controller - cool beaners.
https://www.magnum-dimensions.com/pt...rge-controller

That has a spec'd efficiency of 99% typical with an operational power consumption of 4 watts. Hmm. Lets do the math.

4 watts at 13.1 volts is 305mA (about 3 tenths of an amp). So that is where at least some of that 2.9 amp discrepancy is made up of. Now we're down to ~2.6 amps of difference.

If we reverse the 99% efficiency on your 8 amp charge rate we get: (8 amps /.99) = 8.08 amps. So now we have another 80mA accounted for. So we're down to 2.52 amps difference that the math doesn't explain. That, at the same 13.1 volts, is (2.52 amps x 13.1 volts) = 33 unexplained watts.

Some of that can be explained in power loss in wiring.
Some of that can be explained in heat loss of components, though the 4 watt power loss of the controller is really very small.

If you measured voltage and current at all points in the circuit I am sure you could figure it out. For a theoretical example - if you have 13.4 volts at the output of your PT-100 and 13.1 volts on the input of your inverter/charger you have a 300mV drop between the two - with the same current at both ends. That means you are loosing .3 volts times what ever the current is in power (volts times current is power). In the theory of the missing 33 watts - that would be 110 amps.

The above isn't possible with your set up, because your array isn't likely to be able to produce 110 amps post-charge controller, its just an example of where measuring voltage and current can speak to missing numbers. Paper (or computer screen) can only show numbers to the accuracy of the figures those numbers are derived from - manufacturers specs and practical theory combined here.

 

Wow, you really can respond. I take a ride into Yellowstone NP for the day to view the scenery and possible wildlife.
I really would like to keep going but fear that our conversation has total from the OP intial question even though it shows that there are ways to "glamp" and get power than adding extra cost into an already overpriced tow vehicle/ everyday ride.

If you like to continue I'll copy and paste your reply (besides link back to this thread) in to the thread that you're getting the #s from. Replying properly and giving even more recorded data and potential energy production from the system would take this even further from the OP question I believe. Just let me know.

 

I certainly hope I didn't run the OP off. I can understand the original desire of getting lots of electric service in the boonies to an RV. The subject just hit a nerve - simply the "What does it take to provide x amount of energy" question. That is a question where there are some people that don't understand it. Even after they have paid electric bills for decades. They might understand the dollar equivalent of a kwh in their community, but the energy question - actually providing that compared to how much they use, where it goes, and why - can be total unknowns and gibberish (maybe much like the detail in this thread).

This is a great forum (FTE in general) - I've been around since 2008 or so.

As to the copy/paste - have at it. If you need help or something doesnt come across formatted or quoted correctly (missing quotes 2 deep for example - mine of yours) PM me and I'll open the edits of the posts here to get the correct HTML.

One detail I did not hit on was you said you laid your panels flat on the roof. To me, that is a huge mistake but if you have some theories on it I'd like to hear your perspective and more results.

 

One more thought specifically related to the original question/idea posed in the thread - bringing Ford's offering of AC power in the F150 to the Super Duty class trucks - the challenge, or problem, if you will, ultimately, is the source of the energy.

Most of the sources of energy we have today are:
- Fossil fuels. These are: Gasoline, Diesel, Natural Gas, Propane, Coal, any other product derived from Oil (Black Gold).
- Alternative Energy. These are: Solar, Wind, Hydro (and I'll throw in there wave generators - although this is the motion of fluid, not the displacement of fluid pressure through a turbine), and Geothermal
- Biofuels. These are: Biodiesel, Ethanol, variants of decomposition (from algae, trash, biowaste, etc)
- Nuclear - harnessing the energy of splitting atoms.

The physical solution to the energy problem, if you will, is not to create a "new" form of energy. It is to harness what is already available.

The mainstream societal solution to the energy problem is the acceptance, political support and drive, and commercial implementation to harness and package the forms of energy that already exist. Of course, economics is in that. The underlying theme is that society's energy consumption has historically been built on fossil fuels. Electric cars existed in the late 1800's but fossil fuels won out - economics. So now you have over 100 years of a society that has been built dependent on fossil fuels and we're trying to move away from them.

The most economical energy solution is to "plug in" to the "grid". IE - the power post at a campsite in a campground. The infrastructure that was provided by society to put the post in the campsite with the plug on it, and everything up stream to the turbine that generated the electricity, is what is convenient to you because society built it.

To break away from that you have to understand the challenge, accept it, work with it, and - diverge.

Those that are realizing the benefits of sustainable energy sources today have landed there largely by doing so without the societal acceptance, political support/drive, and commercial implementation. They are leading the way, much like the Wright Brothers making their own airplanes when people thought they were crazy.

That energy ball game is not on the playing field between Ford and it's Super Duty customers. Yeah, Ford is a big company that exists in society and is an innovative company (I'm driving my third Super Duty personally). Their ball game is vehicles. Not energy, although their vehicles are also powered by energy so they inherently deal with the same problem of pushing your F350 and 5th wheel down the road is what, ultimately, your air conditioner conundrum is over. You want to cut the cord and enjoy the boonies where society has not built infrastructure to allow an energy source to reach you while enjoying all the benefits that infrastructure provides. Ford is taxed with regulations to improve efficiency - not just break off entirely from their equivalent of the power grid - fossil fuels. They do so incrementally with hybrid and electric vehicle offerings, but neither solves their conundrum in one jump. Nor can you likely "cut the cord" in one jump, either.

To get to where the energy sources that are here are convenient and mainstream society will have to evolve to allow them. Until then - to realize the benefits of breaking away from the grid and providing the energy for what you use you have to understand it, accept it, and work with it.

That is the attainable near-term solution. Diverge from society and go your own way with one of the sources that exists today. You'll get there a lot faster than waiting for society (through an organization or company offering, etc, though they can help), to provide. You need to drive the bulldozer. Make it your own package, enjoy the ride, and enjoy the blazing of the trail to get you there. Don't let the trailblazing deter you from enjoying the fruits.

 

I was going to try and reply in my other thread but realized it would be way to confusing so if the OP comes back my apology but I guess in a way it follows the thread title just not the original question.

KC8QVO, I'll respond in general to all the previous post and show a general use day "living" of the system.

System consists of 500ah LFMP batteries (5x100ah or 4s5p configuration_ 5,120Wh usable), 1,280w solar_ 8 panels of 160w (2 series, 4 parallel) mounted flat on the roof, Magnum equipment_ PT100 solar controller, 3012 hybrid inverter/ charger, ME-ARC50 (advance remote controller). There is a sub panel added in the 5th wheel so everything is run through the inverter except for the hot water heater. System has been on 24/ 7/ 365 since April of 2016.

The inverter/ charger and the PT100 follow the same charge settings of 14.1v absorb (I'll raise this to 14.2v at times for a couple days if I've been using a PSOC for an extended period of time), float 13.6v, there is always a load on my system so I don't worry about floating the LFP batteries. The inverter has an idle draw of 2ah so just having it always on will be a 48ah in a day on top of what the other loads.

My daily use is 150-275ah daily depending on the season, location, solar length of day.

The solar system is actual wired so another string of panels could be added at anytime for a total of 1,600w but at this present time I don't feel the need for an extra 320w but if I did add that I believe it would eliminate the need for the generator at times except under the most adverse conditions. After 4+ years now the generator might get used 12x a year for a total of 24 hours of accumulated time.

When the panels were wired in the 2s4p configuration that voltage should have been enough for the PT100 "but" when I near 1,200w it will show a P04 code "Power Limited (internal frequency), the P04 power code will show if the output current is being dialed back to prevent the frequency from going to high or low.
Info: The P04 power code can be triggered by sizing the PV array's VOC too close to the battery voltage. If P04 is seen often, the array wiring may need to change to increase the pv voltage input.
The PT100 was a new product at the time and Magnum didn't catch this in the manual for wiring until it was put in the field and used by the consumer. It's corrected in the manual now but wasn't at the time of installation. I haven't seen any issue other than not getting full potential from the panel array over the years now. I'll max about 1,175w and current about 75a +/-. If I add 1 more panel and change my panel configuration to a 3s3p (1,440w) this will correct the occasional code.

Here is an average day during the spring, summer, fall from the system I recorded on 4/20 of this year to give an idea of production/ use.


Looking at the colored headings for the columns the green section is for the GBS battery monitor readings and the yellow from the Magnum remote monitor.
GBS monitor show live time reading at the battery bank voltage, SOC, discharging or charging amps, cell temps on the 20 individual cell with in the pack.
Magnum Display has many screens to scroll through and view all readings of the inverter or the SCC, it's main screen I use is the inverting voltage/ amps.

While charging with solar if you add the charging column of the GBS display and the inverting amp of the Magnum display the total will be what the solar is producing. In the sheet above at 07:30 it's producing 12.9a, at 9:15_ 51.3a, at 12:03_ 74.1a, you get the idea.

Here is the production from the solar for April.

Pretty much self explanatory. I should note that these reading come from the Magnum system so the minimum is from the inverter and not the actual battery bank which will always be higher voltage before the wiring/ inverting inefficiency. I track my SOC% so I can see a lifetime cycle count on my LFP batteries more out of curiosity in a non controlled environment to give an idea how that will compare to what the manufactures claim of what LFP batteries can get. I believe the batteries will probably age out if the end user doesn't kill them in an self inflicted event use. There are roughly 525 full cycles accumulated on the batteries now.

About using the air conditioner if needed... When turning it on the 190a+ is from the locked rotor amps spooling up and will decrease fairly fast (before adding the easy start this hurtle was hard to get over because the generator or the inverter would through a fault and shut the generator down). When I did that test use of little to no solar assisting just the batteries (no generator hook up), the inverting load of the a/c was showing 94a, so if I just use my minimum loads and the sun is shinning the solar panels will cover roughly 60-75a of the a/c load, balance from batteries would be 30ah +/- (6% SoC be depleted per hour).

What would all this data be without the realization of cost, just to put some #s to this for a better perspective financially. When installed after tax credits it cost roughly $9,500. the "payback" would come in the form of boondocking and not having to be in rv parks like I was doing for a couple of years prior to install, my average cost was $25 days when using daily, weekly, months rates during that period of time.

Boondocking Day's since install broken down...
2016_ 200 of 261
2017_ 365 of 365
2018_ 365 of 365
2019_ 344 of 365
2020_ 158 as of today
Total_1,459 of 1,514 days (96% boondocking)

Using the $25 x 1,459 days = $36,475. The initial cost has been recovered plus some more. Beside the ability to "glamp" anywhere, quietly for long periods of time. This was built/ designed for fulltime living with little to no baby sitting of the system.

Today with a little homework a person could easily build a system for a fraction of the price. This isn't for everyone but just my personal experience.

You asked why the panels mounted flat. Once again it's a choice in the build stage. Solar panels are pretty cheap these days so add an extra or 2 to cover the lose of not tilting them.
Something to think about when tilting them...
Is always having to be facing in the perfect direction.
Climbing up and down on the trailer to do this.
Wind, I have been in areas where the wind gusts comes out of nowhere and you better make sure that they are connected to the roof and tilt support bracing is secure.

During the winter season I'll pay more attention to the sunrise and if possible point the nose of the 5th wheel in that direction to get the 480w of solar mounted up front producing as early as possible, then the balance of panels catches the solar arc without shading the balance of panels down the door side of trailer. Bonus of this is the sun stays off the opposite side trailer keeping it cooler for the fridge and majority of windows on that side.

 

Excellent!! Specifically the below chart.



That puts real numbers to what all the theory I tried to convey is all about - exactly why the theory is important.

I assume DoD is off the top - IE you are using that percentage, not the percentage left in the batteries (IE - on 4/1 your use was 38%, leaving 62% in the batteries)?

If you reverse the DoD - on 4/7 you used 44% before sunrise. If we use your usable energy in your batteries of 5120 watt-hours (or 5.120kwh) that comes out to:
(.44 x 5.12) = 2.25kwh energy used out of the battery - your peak discharge state.

Where that gets muddy is for that same time period there isn't a value in there for how much energy was actually used. This would be both production during that period AND the 2.25kwh coming out of the batteries. So, say, in the evening your panels are producing some (little, sun low on the horizon) power. That goes directly in to the load and not the batteries. So your discharge rate of the battery is slowed down, in other words. The 2.25kwh doesn't in and of itself explain that in detail, but that is really cool to see the numbers.

As to the panels being flat - good deal. I can certainly understand all the points you made.

Just to compare my specific numbers - I'm looking at trying to get 6,000 watts (on label) of paneling with an average production of a bit over 17kwh/day, and a WAG (Wild **** Guess) low end production of 1.44kwh (cloudy days). That would potentially be combined with wind power with an average of a bit under 30kwh.

If you run down your harvested KWH column your daily production in that data set ranges from 5.9kwh on the upper end down to 3.3kwh on the low end. My point here is that production varies. To be sustainable that average production has to get you back to the upper end of SOC - which is what your "Battery SOC Evening" is showing - 99-100%. If you go through a period of, say, 2 days of clouds and on day 1 your battery SoC is 65% with the ability to only provide 50% of your consumption you are going to end up with a lot lower SoC on the morning of day 2 than 65%. When you hit the lower limit of our SoC you run out of power = time to fire up the generator.

In the environment I am working with we could go a week with only a kwh or two of solar production. During that time, and during night time even, with the wind blowing we have the option to harness that power as well. So by working with both sources - when we're down in the doldrums on solar production - the idea is to attempt to make up for what doesn't come from solar with wind.

However, one must forward think the problem because you can not sustain on the "averages" over a long period (say, a month or two) if you get stuck in weather that kills your production. Thats the big question mark in what I'm trying to do - and where the depth of these numbers in all the posts here come from. I want to find the balance between what low end production is reasonable to work with to provide our 20kwh or so requirement.

Granted, a sunny day when the wind is blowing we could be generating (in my numbers here) well over 100kwh in a day. If production is able to go to 100kwh in a day - what do we do with the excess 80kwh that we aren't using after the batteries hit 100% SoC? With respect to wind turbines - you have to throw that production to a giant resistor and waste it because you can't leave the turbines unloaded or they will self-destruct. If it is too windy, turbines that are made for low wind speed have to be stopped for the same reason - so they don't self-destruct.

Then take a look at the low end of production. If it is cloudy with no wind and all we get is 1.44kwh of solar through the clouds in a day - we better darn sure have some battery capacity to get us through. If that isn't there - we have to go to generator power and burn gasoline. If we can get by for 2 days on nothing but what is in the batteries (to drain them to our cut off SoC - say 70% used) and we have another 2 days of poor weather - how do we provide what we need for those 2 days on top of charging the battery bank? That would be twice the energy of our consumption that took the batteries to 30% SoC.

Theres a lot of variability in the numbers, for sure. Yeah, there are a lot of numbers, but if you take the time to look at it all and understand the theories of where the numbers are it is very easy math. As you say:
Anyone can do it.

As for price - another good tidbit for anyone reading through on solar panels - you can buy full size panels (usually in the 200 watt class) at auctions for about $50 a panel. Not only that - you can buy them by the pallets at those prices.

If the idea of off-grid living is of interest (more of a permanent set up like what I've crunched numbers to the tune of) - you could potentially get a 20kw (on label) panel array for $5,000. Now, that won't include the brackets/mounts, wiring, and controllers - just the panels. But if you look at buying new panels at $250/panel that is saving you $20,000.... I bet you could put some of that $20k you just saved to brackets, charge controllers, inverters, and wiring...

Just saying...

Somehow when you speak in dollar signs lots of people tend to perk up their ears. That is in contrast to terms like: SoC, KWH, watts, amps DoD, etc, etc. When you diverge you also find significant savings. Take my $20,000 savings above for example.

There are ways.

Think outside the box, jump on that bulldozer, and diverge on your own trail. That's all. It is not hard. It is just not the norm. Though, people like @scraprat are doing this every day.

If people are reading this and are thinking "Yeah, but I just want the power without the hassle" - you need to shift your mindset and realize what you're doing by doing this. How cool would it be to realize the energy independence? That is what the effort gets you - and, I for one, and I imagine scraprat does as well, really enjoy the details. I enjoy the details because those are where the realization of the result comes from. If you can find enjoyment in that - and I hope you do - there isn't anything that can get in your way.

Go do it.