Testing the Waters "Solar"

[homelesshartshorns]

I read a lot about how simple solar is. I understand it can be as simple as solar panel on roof wire to charge controller and connect to batteries! I know about shunts, connecter blocks, fuses and all the other stuff to make it safe. But my questions is? Can it be as simple as the first line of my statement? If I hook up a panel and a charge controller to my batteries will the rest of my system still work as usual or will the solar need something like a Transfer Switch? *

[Kirk W]

Solar is a very broad term. It can be as simple as a small float charger for the chassis battery, costing only $20 from Amazon, or it can be as complicated as some of them from Chad Heiser that will enable you to use your air conditioners when parked without outside power. It just depends on what you want, the size of your budget, and your skill set. 

[Deezl Smoke]

What will the solar "transfer" to/from? Shore power hook up? Generator? Then yes, a switch would be needed.

 Otherwise no. So long as you understand, and I'm guess you do by your statements about shunts, fuses etc., that the panel input is with in the perimeters of the charge controller, or vice-versa, then the charge controller is that simple.

 Expensive and elaborate systems may include a charge controller that has several bells and whistles, and inverters that have their own set of bells and whistles. But since you mention simple, panels input to the charge controller, which steps down the voltages and conditions the output to the batteries, batteries. That's it. Hook your inverter to the batteries, can be on the same terminals as the charge controller, and plug stuff in.

 IMO.

Example: I do not have room in my small rental house to have exercise eq, so I bought a semi trailer and put it in the farm barn that has no other use as it was once a dairy barn built for cows with no other usage intended at the time of build. There is no longer any power at the barn as the cows have long gone. So I put up a cheap hft 100 watt panel system with an hft pwm charge controller, 2 used group 31 truck batteries and a hft inverter. I run my led lights and stepper which has a computer. Been this way for years with not one issue.  Inverter is attached to the same battery posts as the charge controller. The simplest system you can put together. Now if I need to use a generator to charge the batteries because I spent too much time with the lights on, (painting or rearranging eq) then I turn off the controller and inverter to charge the batteries. Works great for me.

[Randyretired]

Solar is used to charge the batteries period.   While many of us  add more that we call solar such as inverters solar is simply a battery charger.   Like other battery chargers it can function in the background providing energy to the batteries and or the load.  Solar charge controllers limit the amount of power to allow the batteries to charge but not overcharge.  This is accomplished by voltage control.  Yes solar can be added without changing anything else.  It will work in conjunction with converters and inverter/chargers.  Meaning if you have solar the RV can be connected to shore power without any special considerations as long as all of the chargers do not provide more amperage than the batteries are rated for. For instance supplying 200 amps of charging to a single 100ah battery will likely cause significant battery damage.

There are various solar charge controllers available but I recommend a MPPT charge controller.  Within the parameters of this type of controller it will change the voltage from higher voltage solar panels to match the batteries voltage.  These also maximize the power from the panels and use smart charging to charge but not overcharge the batteries. 

With the additional power supplied to the batteries many add inverters to provide 120VAC or even 240VAC to power power appliances.  More batteries can be added to provide power after the sun sets.  Solar of course does not mean unlimited power.  A larger solar system can provide more power than a smaller system.  More batteries can provide more power after the sun sets.  With the additional power provided by solar safety concerns are essential.  Proper wiring and fusing are critical.

[Vladimir]

41 minutes ago, Randyretired said:

Solar is used to charge the batteries period..........................

The rest of Randy's statement is also worth reading.  But always remember the first sentence.

You really need both a generator and a solar panel.  Get one of those suitcase panels for a couple hundred dollars and connect it to your battery in the trailer.

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

I own one of these. 

https://www.amazon.com/Go-Power-Valterra-GP-PSK-80-Portable/dp/B009MIPH36/ref=asc_df_B009MIPH36/?tag=hyprod-20&linkCode=df0&hvadid=309845554540&hvpos=&hvnetw=g&hvrand=5240511358936936451&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9033619&hvtargid=pla-568972841751&psc=1&tag=&ref=&adgrpid=60522766686&hvpone=&hvptwo=&hvadid=309845554540&hvpos=&hvnetw=g&hvrand=5240511358936936451&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9033619&hvtargid=pla-568972841751

I actually own several different "versions" of these as they have become rather common.  This is expensive and glass, but still my favorite.  The others I use for my trolling motor on my fly fishing pontoon.

I bought TWO of these and a 100 watt panel Jackery panel to charge both of them.

https://www.amazon.com/Jackery-Solar-Generator-300/dp/B082TMBYR6?th=1

This version is the one I use for my fishing motor.  I bought another one to charge my phone, IPAD, computer, LED desk lamp, stereo speakers, etc.

They are really handy for all that plus it give you a readout on how much power your using.  Well made product.  The new version does NOT appear to be as good.  

There are also other manufacturers now and their products might be just as handy.

 

I have owned a off-grid house for 25 years.  It has a lot of gizmo's and 30 solar panels that all they do is charge my batteries!!!

Solar is a hobby to some, a religious experience to others, and to a minority it is a way to make electricity. 

Focus on the electricity part and you will be fine.  Oh, almost forgot...the electricity is used to charge your batteries.

Edited November 6, 2023 by Vladimir

[bruce t]

Expectations. As long as you can manage your expectations from solar charging all will be fine. Too many folks install solar then expect their RV to act just like the electricity from their outlet in their sticks and bricks. 99% of the time it won't.

 

[Deezl Smoke]

4 hours ago, bruce t said:

Expectations. As long as you can manage your expectations from solar charging all will be fine. Too many folks install solar then expect their RV to act just like the electricity from their outlet in their sticks and bricks. 99% of the time it won't.

 

 And unfortunately they are usually the most vocal anti-solar people after their fail.

[homelesshartshorns]

Solar is a hobby to some, a religious experience to others, and to a minority it is a way to make electricity. 

Now that is funny!

[GlennWest]

actually my solar does more than charge just batteries. My solar also powers my rv. As of now I have power going to my batteries and powering my rv. Batteries just receiving power and supply 12v. I just need some more battery. my acs pull my battery pack down about 3:00 am. 

[Kirk W]

2 hours ago, homelesshartshorns said:

Now that is funny!

So the question is, what do you want to power? 

[homelesshartshorns]

I would simply like a solar system that can charge the house butterises all the time. Plug and play. If I turn on the generator, start the engine or I get on shore power, it does whatever it needs to do to with no attention on my part.

[bruce t]

10 minutes ago, homelesshartshorns said:

would simply like a solar system that can charge the house butterises all the time. Plug and play. If I turn on the generator, start the engine or I get on shore power, it does whatever it needs to do to with no attention on my part.

Yes but that's the problem. Before you can start you need to calculate what you want to take out. It's easy to charge a 100amp house battery. But will 100amp do the job for you? If you want to just run some led lights then great. But what if you want to run more than just the lights?

You cant keep your house batteries 'charged all the time' without knowing what you are taking out and what is required to replace what you are taking out.

 

[Deezl Smoke]

1 hour ago, homelesshartshorns said:

I would simply like a solar system that can charge the house butterises all the time. Plug and play. If I turn on the generator, start the engine or I get on shore power, it does whatever it needs to do to with no attention on my part.

 Scroll through this site.

https://www.victronenergy.com/

 See if you can find a component that fits your need. What you want to do is completely doable and has been done, so somewhere there is a component that can self direct and cancel circuits when you start the gen or prime mover engine.

[Vladimir]

On 11/6/2023 at 1:54 PM, homelesshartshorns said:

I would simply like a solar system that can charge the house butterises all the time. Plug and play. If I turn on the generator, start the engine or I get on shore power, it does whatever it needs to do to with no attention on my part.

Those suitcase units work that way.  You don't need to unplug them.

Buy a hundred watt unit and use that for a month or so.  Then you will have a much better idea on what to buy, how much you need, etc. etc.

 

[homelesshartshorns]

Thanks for the suggestions.

[Chad Heiser]

In the RV world, solar panels and a charge controller are used to charge the batteries.  Once the batteries are charged, those same panels and charge controller can provide “free” DC power for direct use by DC appliances like lights, etc.  The solar panel(s) and solar controller(s) are independent of any of the other charging sources in the rig.  That can work in conjunction with the other chargers without issue.  The caveat to that is that all your charging sources don’t exceed what the batteries can handle.

My solar charge controllers (three of them) are always on.  They are on to provide power when I am boondocking.  They are on when I am sitting in an RV park connected to a 50 amp pedestal.  They are on when I (rarely) run my generator.  They do not interfere with shore power or generator power.  They are simply there to keep the batteries charged.  If the batteries are full, then they simply ramp down and just float the batteries.

[homelesshartshorns]

On 11/7/2023 at 10:11 PM, Chad Heiser said:

In the RV world, solar panels and a charge controller are used to charge the batteries.  Once the batteries are charged, those same panels and charge controller can provide “free” DC power for direct use by DC appliances like lights, etc.  The solar panel(s) and solar controller(s) are independent of any of the other charging sources in the rig.  That can work in conjunction with the other chargers without issue.  The caveat to that is that all your charging sources don’t exceed what the batteries can handle.

My solar charge controllers (three of them) are always on.  They are on to provide power when I am boondocking.  They are on when I am sitting in an RV park connected to a 50 amp pedestal.  They are on when I (rarely) run my generator.  They do not interfere with shore power or generator power.  They are simply there to keep the batteries charged.  If the batteries are full, then they simply ramp down and just float the batteries.

I might ask this questions. With solar panels and a simple mppt controller can I simply hook to my batteries and then start my rig or generator and the controller will not allow feed back on my solar system? if the answer is no then can you show me the switch I need so I can ?

[Chad Heiser]

13 hours ago, homelesshartshorns said:

I might ask this questions. With solar panels and a simple mppt controller can I simply hook to my batteries and then start my rig or generator and the controller will not allow feed back on my solar system? if the answer is no then can you show me the switch I need so I can ?

Yes you can.  You can have multiple charge sources going to your batteries at once like an MPPT and a converter or inverter charger, etc.  There is no need for any additional equipment.  This assumes the proper size wiring and fusing is in place.  It also assumes the sum total of all your charge sources isn’t more than what the batteries can accept/are rated for.

Edited December 13, 2023 by Chad Heiser

[homelesshartshorns]

7 hours ago, Chad Heiser said:

Yes you can.  You can have multiple charge sources going to your batteries at once like an MPPT and a converter or inverter charger, etc.  There is no need for any additional equipment.  This assumes the proper size wiring and fusing is in place.  It also assumes the sum total of all your charge sources isn’t more than what the batteries can accept/are rated for.

Thank you. And yes, assuming I have installed all things with right wire and fuses, the MPPT will stop the solar from charging too much and the house Transfer switch and inverter/charger will stop the generator from charging the battery's too much and the alternator has a gizmo to stop it from over charging the batteries. So once all is in place it will all take care of itself!

 

[homelesshartshorns]

Ok bring you all up to date on my solar project. I got the kit installed and all went well for about a week. But on the second week my panels have stopped producing power and so I am stuck. I can find no loose connections, and all seems to be as it was before I hooked up the panels to the controller but now no power. 

I must say I was quite impressed at the ease of installation, and all just seemed too full into place. But now I don't know what to look for. The instructions are all very good as to the install and steps to take. But nothing is mentioned as to what to look for if it stops working. So, I will let you know what I find out. Safe travels

[Chad Heiser]

6 hours ago, homelesshartshorns said:

Ok bring you all up to date on my solar project. I got the kit installed and all went well for about a week. But on the second week my panels have stopped producing power and so I am stuck. I can find no loose connections, and all seems to be as it was before I hooked up the panels to the controller but now no power. 

I must say I was quite impressed at the ease of installation, and all just seemed too full into place. But now I don't know what to look for. The instructions are all very good as to the install and steps to take. But nothing is mentioned as to what to look for if it stops working. So, I will let you know what I find out. Safe travels

Disconnect the panels from the wire leading to the solar controller.  Use a multimeter and check voltage on each panel by inserting the meter probes into the pos and neg pigtails coming off the panels.  This will tell you if the individual panels are producing electricity.  If they are, reconnect the panels to the wiring and go to the next junction in the wiring and do the same thing.  Keep going until you find where there is no power.

[homelesshartshorns]

Will do thanks.

[homelesshartshorns]

On 2/3/2024 at 1:20 AM, Chad Heiser said:

Disconnect the panels from the wire leading to the solar controller.  Use a multimeter and check voltage on each panel by inserting the meter probes into the pos and neg pigtails coming off the panels.  This will tell you if the individual panels are producing electricity.  If they are, reconnect the panels to the wiring and go to the next junction in the wiring and do the same thing.  Keep going until you find where there is no power.

Ok there is no power getting past the 10-amp 1000-watt inline fuse on the roof. If I take it out of line, all comes on again. So, is the fuse too small or should I consider that the panels are wired wrong? I have it set up in two panels in series and then those two are in parallel. 

[homelesshartshorns]

Run this by you all! As I read it using partial series and parallel has more short circuit power then if i was to run the four panels in series. In series I can use a smaller 10 amp / 1000-watt inline fuse or even no fuse! Am I thinking this right?

[Lou Schneider]

You really don't need a fuse between the solar panels and the charge controller.  Unlike a battery or a conventional power supply that sends humongous amounts of current into a short, solar panels will NEVER produce more current than their rated Short Circuit Current (Isc).  This is only a few percent above the Maximum Power Point current so if your wiring can handle normal current it can also handle the slightly higher current the panels will send into a short.

Likewise, if a fuse is sized to handle the solar panel's normal output the current will stay low enough to keep it from blowing if the wires are shorted.

Where you DO need fuses are on the battery side of things to interrupt the huge rush of current if something shorts there.

Edited February 5 by Lou Schneider