Solar Updates

Preview commercial:  We have done several Solar installs on RV – using ContinuousResources.com.  (Affiliate link) I can’t say enough good things about them, so if you are looking at doing an install – I suggest contacting them both as a resource and supplier.

Review: Just over a year now since we installed solar in our class A motorhome.  We had 400 A/hours of Lithium batteries.  We installed 800 watts of panels, a Victron MPPT solar controller, a Victron 3k inverter charger and a Victron battery monitor.  We also added a Victron Color Control Console, as a “not necessary”, but as it turns out, quite a useful device.

It looks something like this:

Sample Solar diagramSo, how does it all work?  In a word: Great!

On my RV – most of the electrical system had few if any ability to monitor operations.  If I slid the drivers seat back and opened the overhead cabinet, I could see and have some control over the Inverter status.  The Spyder system showed me the house battery voltage.  That is it.  Most Victron devices can communicate with Bluetooth (though some require a dongle).  So, while in or near our RV, we can monitor the various parts of the system. And most often, that is the method I use to just check on the battery status or how much solar do I see.  But with all the metal framework, Bluetooth has its limitations.  For example, sitting all the way in the front of the RV – my phone doesn’t see the solar controller that is way in the back-left compartment.

Victron Color Control Console

 

 

 

 

 

 

Enter the Color Control Console (CCC).  All the Victron devices are connected via their V.E. bus.  They can share data (such as the Inverter and solar controller can read the battery voltage from the battery monitor).  All the devices share their data with the CCC.  The Console is mounted inside a back closet and I can flip through menus and see what is happening in my entire system.  But I don’t do that very often, as I can also access the CCC via Bluetooth AND the internet.  The CCC connects back to vrm.victron.com through our hotspot, where it both uploads operational data and provides a back connection from Victron to my CCC.  Thus, I can access my CCC either via an app on my phone or via a web address.  The server also stores the operational data which can be retrieved via the web site.  I can review how the system has been doing yesterday, last week, this month or the entire year.  In the example iPhone VRM app sample to the right, you can see the week we were boondocking with only partly or fully cloudy days.  The rest of the days shown we were at electric hookup sites.  The peak input from solar was only about 500watts, but then we are up in the foggy, cloudy, far-north Oregon and Washington state.  That is why having more panels that you think is an expense, but also an advantage.  The bright summer sun isn’t always overhead.  The Victron system shows the solar system has supplied 400Kilowatt hours since it was installed just over a year ago.  That translates to approximately 310 hours of generator time saved.  Since solar supplies some power to the coach whenever there is sun and DC power draw, that is probably an overstatement, but solar is working, not just loafing on the roof.

 

The left image is from the Battery Monitor, as is the middle – showing historical numbers.  The right shows real-time voltage and current data for the batteries accessed via the VRM iPhone app.  There is so much more.

We run an Apple TV, along with several hours per day of television, a large residential refrigerator, the furnace some at night, several computers for a few hours and a CPAP all night.  We use around 200 to 400 Amp-hours of battery most days and when it is sunny, solar keeps up with that easily.  When we cook a substantial meal in the RV, we use even more as most of our cooking is with electric appliances. (microwave, induction burner, air fryer).  If the batteries are headed for 50% and we want to cook something that will take a long time (30 minutes), we sometimes will fire up the generator to take up the cooking load as well as put some power back into the batteries.  We have a 7000-watt generator (2 * 3500 watts), and running that just to charge batteries is a waste of gas and generator time, so we try to get more use when it is running.

We don’t currently have the ability to run an Air Conditioner from our inverter, though it should be possible.  The Air Conditioner power doesn’t feed through the inverter.  I do have a smart start box (yet to be installed) for one air conditioner and with a simple wire change and a switch, I could cut one of air conditioners to the inverter feed and could briefly run the air conditioner off the inverter and lithium batteries.  Ideally, I would need to add a few more batteries and another round of solar for that hookup to make sense.

The 3000 watt Victron inverter/charger was an optional part of our solar installation process.  The RV came with a 2000W Magnum.  Between it and the resistive power connection, it was no end of trouble.  There were many combinations of appliances that would overload the 2k watt unit.  I really like several of the features of the Victron.  First – it picks up power flawlessly when outside power goes off, the generator is shut off, etc.  Second – I can program it to limit power usage when I’m on a smaller power pedestal.  If I’m on a 30A or even 20A – I program that in from my phone and any time power draw, through the Inverter gets too high, it uses battery power to supplement.  Now, this isn’t quite as simple as setting it to 20 or 30, because the Victron only sees power going through it – so the air conditioners and electric fire place for example use power it doesn’t see.  So I will usually set the power draw lower and let it use the batteries when needed.  Third, the extra 1000 watts above the Magnum mean we can use many more combinations of appliances without worrying about the inverter kicking out.  Lastly – with most of my power management all from the same vendor, all accessible through the same interfaces, it is much easier to monitor how things are working.

When our RV is in storage – I leave the Solar connected.  It keeps the batteries charged and runs the Ring doorbell, internet hotspot and cell repeater so everything stays charged and we can remotely keep tabs on the systems and the RV.

The solar install we did on our daughter’s class A is also doing well.  They do not yet have an updated Inverter (theirs is only 1200 W), so they often end up running the generator when cooking with electricity.  A Victron 3k is on their “someday soon” list.

I’m very happy with all my solar equipment, that I got through ContinuousResources.com.  (Affiliate link)  I highly recommend you consider them if you are going to build a system.

mgg

Covid Solar Install

Solar in a Covid world….

Working between storms or under rainbowsWe were in a private campground, near home in Central Illinois, waiting to see if the whole virus thing winds down a bit as states reopen as well as making repairs, adjustments and upgrades on the RVs before, hopefully, heading out west to higher, cooler altitudes for the summer. Plans, right?  We could go home to swap tools and RV stuff from the garage and did make a foray or two into the house with PPE gear on.  Our son and his family share our house with us and two of them are front-line healthcare workers.  Since we are in the 65+ club, we simply can’t move back in right now.  We can’t get careless with exposure to Covid.

When we started RVing, we were just taking long vacations (we were retired).  Then snowbirding became a thing.  We had been seriously discussing going full time or near full time (with small home base somewhere south below the snow belt), but we have way too much junk at home to make the transition.  Our plan had always been to travel a few months, then come home and get rid of stuff before hitting the road again.  We left home last November for the Gulf Coast and it looks now like we won’t be home to live until next spring; well over a year in our RV.

We are isolating with our daughter and her family in a small private park in central Illinois before heading out west.  RV#1 (ours) already had 800 watts of solar from an install we did a year ago.  RV#2(theirs) had no solar, but it did have over 500 amp-hours’ worth of lithium batteries installed.  It also has a 1200 watt modified square wave inverter/charger (inadequate).  The battery bay was on the right, the inverter on the left.  They wanted solar so we could boondock together and get a bit closer to nature.

Unboxed panelsThey ordered the solar panels and equipment from ContinuousResources.com.  (Affiliate link)  We ordered four 200-watt panels, brackets, cable, a combiner box, and a mini-circuit-breaker box, all of which arrived quickly, and thankfully considering the virus was already in full swing around the country.  What we didn’t order was a solar controller.  Somehow, in the confusion and rush, I managed to convince myself the controller he salvaged from the solar install on their previously owned RV would work.  And, well, it would have worked, sort of… Technically it supported enough volts and incoming amps, but couldn’t output the wattage.   It just wouldn’t have let anywhere near 800 watts of power get to the battery.  We discovered this just before starting the install and so after a short panic, quickly figured out which controller and found one we could get quickly.   Fortunately, it arrived just in time as we were working our way down from the roof with cable,  toward the batteries.

Help installing bracketsThe design included the possibility of adding more panels in the future, so the wiring and combiner box allowed for up to four more panels (though on this RV, that would be tight).  We positioned these first four panels forward and away from the AC’s and vents as possible for the least amount of sun interference.  Based on previous installs we had done; we chose to use ½ inch by 1 inch well nuts with ¼-20 stainless bolts for mounting.  We set the panels in place, marked the holes, moved the panels away, and drilled out the holes.  We intentionally drilled the holes a bit small and hand adjusted with a Dremel until the well nuts just fit in snug.  We put butyl tape around the well nuts before placing the brackets (panels) and put self-leveling sealant all the way around the brackets and over the bolts.

For the roof-top wiring, we used 10-gauge solar wire (red/black) and connected them as two sets of serial panels, with inline fuses and combined in parallel in the box. Thus, at full sun exposure, we can expect around 45 volts and almost 20 amps headed toward the MPPT controller.

From the combiner box, we ran 4 AWG cable, down the inside of the back cap. Yes, that is probably a size larger cable than we needed, but because future expansion was a possibility as well as the fairly long run, we opted for that size.  Because we wanted to put the combiner box on the right side as was the same position of the ladder, the box went several feet forward of the ladder and we extended ¾ PVC electrical conduit back to the rear cap. We put the split wrap on the entire length of the down run and clamped and tie-wrapped as necessary all the way to the battery box.  Then the real fun begins…

I didn’t really get much of a chance to see this RV when it was new.  Some work had been done on it, for example,Solar Installation
to change out the lead-acid batteries to lithium.  But they were, as told, in theory, connected exactly the same way as the lead acids were done at the factory.  There was a block fuse on one wire leaving the battery (to feed most of the 12V DC for the house.  There was a separate breaker for the wire going to the hydraulic motor for the jacks.  There was a wire (4/0) going to the Inverter that had NO FUSE!  While the inverter has its own internal breaker – fuses at the battery are there to protect the cable going FROM the battery to a remote device.  Not having a fuse/breaker on the inverter cable means there is no way to remove power to the inverter except getting out a wrench, and it also means if someone were to run into the RV at the inverter side – the full current of the batteries would be available for sparks, flame, and ball lightning.  One must still get out a wrench, but it is just to loosen the fuse, but at least without leaving wires hanging.  An actual Inverter power switch is on the todo list as is, someday, a bigger better inverter.

So, we then installed a piece of plywood in the back of the battery bay to mount everything.  Secured a large fuse holder, a ground bar, the new solar controller, and the mini breaker box, and began wiring.  We scrounged up spare cables and built the ones we needed. (I have a hydraulic crimper and had ends left over from other solar jobs).  Once we had all the parts ready and a process lined up, we turned off the inverter and coach power and proceeded to replace cables as needed and reconnect everything.  The 4-gauge wire was a bit of a problem as the solar controller wasn’t built for that heavy a wire, so we trimmed those wires down a bit to fit.  The controller is just big enough for the 4 panels, so a new controller would be needed if they added panels and a bigger controller would have more connector space for the 4-gauge wire.  When we were all done, the sky was a fairly heavy overcast and the batteries were mostly charged (they had been plugged into camp pedestal), but they still were putting out 254 watts (18 amps) into the lithium batteries.

West across Wyoming
West across Wyoming

finished from the rearAll told, it was a successful install.  It took two of us about two and half workdays working between rainstorms.  We are now headed out west for some boondocking.