Gave solar a try and happy with results

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Dragginourbedaround

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Joined
Jul 15, 2013
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Location
Southwest FL
We spent 13 days dry camping at the Albuquerque Balloon Fiesta. So we thought this would be a good time to try solar. We bought a Renogy 100 watt suitcase kit and an extra 20' of 10 AWG wire. We had plenty of sun for most of the time we were in Albuquerque. With the extra 20' of cable we could move the panels twice a day to the front and back of the coach to maximize sun exposure. Really happy with the results. On average most days we were at 12.4-12.8 volts most during the day. If we were running a radio, computers or charging phone and tablets it would drop to 12.3 or 12.4. At night with lights on and the TV and satellite receiver running it would get down to 12.1 or 12.2.  We only ran the generator on average 3 hours a day. Compared to spending two weeks at Q in March of 2016 where we ran the generator at least 6 hours a day with no solar. We plan to to spend more time boon docking in 2018 and will add another 100 Watt panel. The kit came with a 20 amp controller so we can add up to 300 more watts. We have 210 ah of battery and think another 100 watts should cut our generator time a little more. In Albuquerque we were so busy we didn't have time to experiment with our new solar. We are in southern FL for the winter and will put out our panel(s) and experiment with what we can and can't run. This solar newbie is open to any and all solar advice.  :)   
 
My advice is read the following:

https://handybobsolar.wordpress.com/

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

http://www.marxrv.com/12volt/12volt.htm

More than you ever want to know about solar.
 
kdbgoat said:
My advice is read the following:

https://handybobsolar.wordpress.com/

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

http://www.marxrv.com/12volt/12volt.htm

More than you ever want to know about solar.

All good links and  must first stops to learn about solar and how best to apply for RV's.
 
During the day with the solar panels charging you should have seen 13 plus volts at the batteries. or did I miss something?
 
During the day with the solar panels charging you should have seen 13 plus volts at the batteries. or did I miss something?
i did see voltages in the 13s, but unless I didn't have anything running it didn't last long. As I said earlier the avg was mid 12s.

With 100 watt panel , 210 ah battery and various things running; I think the readings are in the ball park.
I'm hoping with the addition of another 100 watt panel I can get the batteries to stay in the mid 12s overnight.
 
More is better
No one ever says they bought too much solar
I like the rule of thumb of about 150 watts per 100 ah of battery. You may also want to think about the future before investing more. Just say you end up wanting a 600 watt system then it's probably cheaper and more efficient to buy it all at one time and it also avoids miss matched panels etc.  Some miss match isn't always critical but if you have a choice, avoid it.

You do get a good boost in performance when you can ground position the panel and  roof mounts also benefit from tilting or add more panel if leaving flat. If you do go to 300 watts as portable you will be very happy with it. There is no bad solar.
 
Dragginourbedaround said:
We spent 13 days dry camping at the Albuquerque Balloon Fiesta. So we thought this would be a good time to try solar. We bought a Renogy 100 watt suitcase kit and an extra 20' of 10 AWG wire. We had plenty of sun for most of the time we were in Albuquerque. With the extra 20' of cable we could move the panels twice a day to the front and back of the coach to maximize sun exposure. Really happy with the results. On average most days we were at 12.4-12.8 volts most during the day. If we were running a radio, computers or charging phone and tablets it would drop to 12.3 or 12.4. At night with lights on and the TV and satellite receiver running it would get down to 12.1 or 12.2.  We only ran the generator on average 3 hours a day. Compared to spending two weeks at Q in March of 2016 where we ran the generator at least 6 hours a day with no solar. We plan to to spend more time boon docking in 2018 and will add another 100 Watt panel. The kit came with a 20 amp controller so we can add up to 300 more watts. We have 210 ah of battery and think another 100 watts should cut our generator time a little more. In Albuquerque we were so busy we didn't have time to experiment with our new solar. We are in southern FL for the winter and will put out our panel(s) and experiment with what we can and can't run. This solar newbie is open to any and all solar advice.  :) 
Did you have the fridge switched to the gas only setting?  I am reading that a number of Winnebago MH's have the fridge wired through the inverter.  If the fridge is going through the inverter, and the fridge setting is on auto it will use LOTS of power from your batteries.

If the fridge is indeed running on gas, then your 5 year old batteries have lost a lot of their capacity.  Running your generator for 3 hours a day & topping off with 100 watts solar in you should not be dropping down to 12.1V.  If you replace your batteries go with 6V golf cart batteries.  Read the links given earlier for more info.

Be sure to run your generator first thing in the morning, and then let the solar take over. 

BTW the satellite receiver is a power hog.  Be sure to unplug it when not in use.  It pulls pretty much the same power whether or not it is used, as long as it plugged in. 

Also turn off the inverter when you are not using devices that need 120V AC.  The inverter just being on and not powering anything takes 30-50 amp hours (AH) in 24 hours (1.5 to 2amps just being on).  That is more than what your 100watts of solar can replace in a day.

Additionally if you are going to be doing quite a bit of dry camping you need to have a battery monitor like a Trimetric:  http://www.bogartengineering.com/products/trimetrics/  Otherwise you are flying blind as to the charged/discharged condition of your batteries.  Trying to use the voltages to guesstimate your state of charge is just guessing at your charge level. 
 
AZtraveler
x2 on the satellite draw. Which inverters draw that much power? I guess I'm doing great with my Prowatt 2000 only using .5 A
 
I like the rule of thumb of about 150 watts per 100 ah of battery. You may also want to think about the future before investing more. Just say you end up wanting a 600 watt system then it's probably cheaper and more efficient to buy it all at one time and it also avoids miss matched panels etc.  Some miss match isn't always critical but if you have a choice, avoid it.
I always thought the rule of thumb was one for one, but I haven't read those links above yet. I don't see us needing 600w of solar. If I can get the generator run time down to a couple of hours a day we'll be happy. If we do decide to go with lots of solar, then we'll sell the portable and go with what the installer recommends. At that point it will be more than just more solar panels that we will need.

AStravelers

The fridge was on LP and eventually we learned to unplug the TV, the sat receiver and turn off the inverter before going to bed.
Generator hours were from 5 am to 10:30 pm, so we ran the generator for 1.5 hrs when we got up and 9-10:30 pm most of the time. 
 
Howdy,

Dragginourbedaround said:
I always thought the rule of thumb was one for one, but I haven't read those links above yet.

I have read them (quite some time ago) and remember reading the rule as 1:1, so either they got updated, or my memory is tripping me, or  QZ is operating by the "what deserves to be done. deserves to be overdone" rule ;-)

Seriously, great info here, specially the tip on starting the generator early, then letting the solar take over. I haven't thought about it until reading this, but ẅith Lead-Acids the generator will then maximum efficiency for the "bulk" charging stage, and the final (and slow) "topping" stage gets done by the panels and doesn't waste fuel.

Cheers,
--
  Vall.
 
QZ said:
More is better

This is an internet myth that dictates more solar is better, which is not always the case.  It is of course true solar has to be sized correctly for the battery bank being used and for the anticipated usage but far too many pay more attention to throwing more solar panels on the roof and/or portable, than efficiently wiring the system.  Wiring using correct gauge and the shortest run, particularly between the controller and the battery bank maximizes efficiency and often means not having to buy that extra panel(s).  As an example I just completed the solar install on our new truck camper which came with 1-100w panel.  Knowing most manufacturers solar wiring is usually poor and inefficient, the first thing I did was run a little test.  I pulled the charge controller from the living area where it was installed and temporarily set it in the basement next to the batteries and replaced the 10 awg pre wire with 6 awg to the controller and from the controller to the batteries.  The result was a 10% increase in power from the 100w panel over the original installation.  After replacing the controller that came with my rig with a much better unit and shortening the run from the panels via a combiner box to the controller and again using 6awg wire instead of the 10 awg provided to the controller, I realized another 5% gain for a total of 15% when all was said and done.  To complete the install, I then added the 2-160w panels from my previous rig which served us quite well, and all that we really needed, but since my rig came with a solar panel, I kept it.  Had my rig not come with the panel, based on experience with my previous rig, I would not have needed to invest in any additional panels.
 
Another problem that folks have with their solar is not correctly charging their battery bank to achieve the full potential of their batteries. Read Handy Bob's battery charging puzzle. It explains this very well.

https://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/

Using the analogy of a gas tank on your car, the object is to get as far down the road as you can on a tank of gas. If you start out with less than a full tank, you obviously won't get as far down the road.
Even when charging with a generator, if you don't have enough volts going to the battery bank, or don't charge long enough to fully charge the bank to get it to the true float range, you won't get the "mileage" out of your battery bank. Just throwing extra solar panels at a solar charging system won't change this.
 
Gizmo said:
This is an internet myth that dictates more solar is better, which is not always the case.  It is of course true solar has to be sized correctly for the battery bank being used and for the anticipated usage but far too many pay more attention to throwing more solar panels on the roof and/or portable, than efficiently wiring the system.  Wiring using correct gauge and the shortest run, particularly between the controller and the battery bank maximizes efficiency and often means not having to buy that extra panel(s).  As an example I just completed the solar install on our new truck camper which came with 1-100w panel.  Knowing most manufacturers solar wiring is usually poor and inefficient, the first thing I did was run a little test.  I pulled the charge controller from the living area where it was installed and temporarily set it in the basement next to the batteries and replaced the 10 awg pre wire with 6 awg to the controller and from the controller to the batteries.  The result was a 10% increase in power from the 100w panel over the original installation.  After replacing the controller that came with my rig with a much better unit and shortening the run from the panels via a combiner box to the controller and again using 6awg wire instead of the 10 awg provided to the controller, I realized another 5% gain for a total of 15% when all was said and done.  To complete the install, I then added the 2-160w panels from my previous rig which served us quite well, and all that we really needed, but since my rig came with a solar panel, I kept it.  Had my rig not come with the panel, based on experience with my previous rig, I would not have needed to invest in any additional panels.

No myth and none of this is one size fits all.  Wiring for the smallest % of loss is a given. I always need 700 to 800 watts but when it's totally overcast and my 1000 watts is still putting out 5 amps more is better. Panels are dirt cheap so it's just like engines, there is no replacement for displacement.  More is better just means that if a person leans to the side of having more they will then have more coverage when the conditions are less than ideal. In the same respect it's often recommended that if a person doesn't want to tilt just add a panel or two. It's very common for people to want to add more when they realize how well solar works. Maybe it's just me but I have never ran into anyone who said they bought too much.  Any time that has to be made up with a generator is the most expensive time of all. Nothing wrong with a  generator and it can be part of an energy management plan. A lot of choices and variables.

As mentioned, it's helpful if a person buys their last system first rather than adding mismatched components later. Even if it is a little more than they need it will never harm but may often help.
 
QZ said:
No myth and none of this is one size fits all.  Wiring for the smallest % of loss is a given. I always need 700 to 800 watts but when it's totally overcast and my 1000 watts is still putting out 5 amps more is better. Panels are dirt cheap so it's just like engines, there is no replacement for displacement.  More is better just means that if a person leans to the side of having more they will then have more coverage when the conditions are less than ideal. In the same respect it's often recommended that if a person doesn't want to tilt just add a panel or two. It's very common for people to want to add more when they realize how well solar works. Maybe it's just me but I have never ran into anyone who said they bought too much.

As mentioned, it's helpful if a person buys their last system first rather than adding mismatched components later. Even if it is a little more than they need it will never harm but may often help.

When as stated before "more is better", one really needs to define what more really means,  To use your example where you say you require 700-800 watts of solar panels to service your usage, but having the extra 200 watts when it is overcast or cloudy comes in handy to provide an extra 5 amps makes perfect sense and in your case more is indeed better, I certainly get that.  In fact I suspect I will find the same to be true by having the extra 100watt panel on those low solar days will be a real benefit.  Where I find "the more is better" ideology without merit, is where systems are inefficiently put together and then buying more solar panels to compensate, or those who fail to determine their energy needs and then buy panels because of what someone else may have or to fill available real estate on the roof.  Maybe you have deeper pockets than I, but while solar panels have come down considerably in price, I hardly think they are dirt cheap.  Having to buy extra panel(s) if I do not need to, is a savings I will happily take.
 
Gizmo said:
When as stated before "more is better", one really needs to define what more really means,  To use your example where you say you require 700-800 watts of solar panels to service your usage, but having the extra 200 watts when it is overcast or cloudy comes in handy to provide an extra 5 amps makes perfect sense and in your case more is indeed better, I certainly get that.  In fact I suspect I will find the same to be true by having the extra 100watt panel on those low solar days will be a real benefit.  Where I find "the more is better" ideology without merit, is where systems are inefficiently put together and then buying more solar panels to compensate, or those who fail to determine their energy needs and then buy panels because of what someone else may have or to fill available real estate on the roof.  Maybe you have deeper pockets than I, but while solar panels have come down considerably in price, I hardly think they are dirt cheap.  Having to buy extra panel(s) if I do not need to, is a savings I will happily take.


If you say is where systems are inefficiently put together and then buying more solar panels to compensat isnt a more is better issue, that's a poor install issue.  what someone else may have or to fill available real estate on the roof If they do fill the whole roof and they dont have to run the genny as much or they may get more power in lesser conditions or partial shading because of campsite location or angle. The initial cost of the system has gone in so the addition of a panel or so is the cheap part of expansion. That's why I often tell people evaluate carefully for what they might also want to power when they realize they can do a lot with solar and it's great stuff.

Another way to picture more is better is if you talk to a lot of people or hang around solar stores etc you will find that people are often adding to their systems and never want to get rid of panels.  I'm just one person but I have never heard anyone say that they bought too much. Many times when a person tries solar they have a tendency to wonder if it's a waste of money or can it really do what they want etc so they do more of a minimal install so it is best to lean to the more side. If you talk to people about what they think they need and what they really need they are just about always under sizing.

So more of my money is staying in my pocket when the suns kicks any generators azz. The most expensive way to get off grid power is with a generator. If you want a lot of power fast you are stuck with a genny but $/watts  solar wins all the way
 
I would also say that when I say that I could get by on 7 to 800 that is in ideal conditions in dead of winter in Socal tilted. For my battery bank size I could use 100 amps of charge but do pretty good on 50 to 55. Another problem with some solar installs is that they are borderline and often suffer from incomplete charges.
 
All this back and forth about myths, wire size, efficiency, yada, yada, yada.

Much earlier in this topic the below links were given.  Go to those links, READ and UNDERSTAND the info given.  Even if you are going to use an installer, read and understand the info in the links and you will know if the installer has your best interest at heart or just wants to sell what they make the most money on. 

kdbgoat said:
My advice is read the following:

https://handybobsolar.wordpress.com/

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

http://www.marxrv.com/12volt/12volt.htm

More than you ever want to know about solar.

Here is another link to add to the above:
http://www.rv-dreams.com/rv-electrical.html
 

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