New Project, Solar for Class C

[HueyPilotVN]

Final Pictures:

I put the finishing touches on the project.

Here are some pictures.

I attached the Lexan Safety Panel in place.

It is attached with industrial grade Velcro on the back. I also added additional straps on the top sides to make sure that it stays attached. After pulling off the protective plastic it really shows off the shelves.

I think that I will call it the "Bubba Edison Electric Company". All it really does is that it provides lots of 110 AC to the main panel, mostly from Solar.

It is too cool today to do a good test of the run time using the air conditioner.

You can see half of the cooling fans and one of the vents.

The Master controller and system monitors are mounted next to the bed.

The Solar charge controllers panel mounting system looks kind of messy but there is a method to the madness. The entire panel is mounted on a "J channel" to the closet wall. I can remove it to do any work on it. The is why I have the extra cable length that folds out of the way.

The charge controllers have circuit breakers on the input from the panels and fuses on the output to the batteries.

 

[Larry N.]

Nice!

 

[HueyPilotVN]

Thank you,

I just organized and put all the stuff back into the rear storage area and it fits with room to spare.

 

[HueyPilotVN]

Initial conclusions or at least theory on running Air Conditioning when boon docking.

This is just my impressions on how the system will perform in real conditions.

I am going to attempt to be conservative on my projections although they are partially based on real initial data from the monitoring instruments.

While operating at 4:00 PM the other day the solar input to the battery bank was 99 amps from the three combined but separate charge controllers with NO charging from the Inverter/charger by outside 110 volt A/C from the shore power or generator.

The current draw from the output of the inverter provided by the battery bank was about 120 amps to the main panel while running the air conditioner.

This equates to a negative depletion of the battery bank of about 21 amps. To be very conservative I am going to use a negative draw of 50 amps to do the following projections. There are other considerations such as diminished solar output or increase auxillary loads on the main A/C panel.

I am projecting that a 50 amp/hour loss from the battery bank would give me 8 hours of air conditioning. (for example 9 to 5), using 400 amp hours of 900 amp hour capacity. The battery bank theoretically would still have a 55% State of charge, (SOC(.

At that point without air conditioning the remaining capacity would easily supply the 110 volt A/C needs for the night.

If needed the air conditioning could still be used for an additional period.

All of the DC power requirements would be handled by the extra 200 amp hour original AGM batteries that would be at full charge after being charged at float level all day by the original factory converter/charger.

The next morning the battery bank could be brought back to full charge by using the 150 amp charging current from the inverter supplied by the regular generator plus the input from the solar panels for an additional 80 or so amps for a charging current of about 230 amps. this would recharge the bank to 100 SOC within two hours to restart the cycle.

The multiple charging inputs is similar to filling a swimming pool with more than one water hose.

Other than the real initial data on A/C load with the air conditioner running and the data on real measured solar charging input, this is somewhat theoretical until tested with real world conditions.

The cooler weather has made a real test not necessarily accurate. The real test will be in hot weather.

I am sure there will be more things to consider on the performance of this system.

 

[Lou Schneider]

So when are you taking the rig out instead of just working on it in your driveway?

 

[HueyPilotVN]

Well, I am taking it over to South Side Welding here in town so that they can reinforce the receiver hitch to make it safer to tow my 7,000 pound Jeep. The receiver is rated for 5,000 pounds now.

I am planning on definetly doing QZ this year.

 

[Ex-Calif]

Looking forward to some real world data.

My initial concern is that if you end the daylight hours with 500 amp hours remaining and the AC draw is 120 amps, you have a theoretical night time run life of about 4 hours to 0 SOC.

There are a ton of places you may need AC all night.

On the pro side in those same areas you may not need AC from say 3am to about 11am.

If you end the night with 100ah or so and have a 100 amp collection rate for 7 hours it's possible to build up a large deficit.

Real world will let you know and of course you are definitely smart enough to monitor what is going on and adjust as needed.

 

[HueyPilotVN]

I think that the backup solution is to simply start the generator. The charge current thru the Inverter is 150 amps even without any solar at night.

I suspect that the 4K generator will run the A/C and charge the batteries. Future data will tell.

The auto start for the generator will kick in at the trigger voltage.

That is what I would do if I did not have the system.

I have no problem running the generator. For me this is mostly an exercise to see if it can be done on a Class C.

I know that it can be done with more roof space and batteries.

This has not been a real practical solution but rather a learning experience.

Thanks for the input.

 

[HueyPilotVN]

I still have not done a full timed test on how long the Air conditioner will run because it has been so cool that I think it would not be accurate due to cycling.

I do have an interesting fact to share. I was running the A/c and turned on the microwave. The 400 amp fuse between the monster batteries and the inverter blew. I must have pulled more than 400 amps from the batteries.

When the temperature warms up I will do an all day test.

 

[HueyPilotVN]

I thought that I would do something else to finish off the project.

Earlier in the project I called it the "Bubba Edison's Solar Electric Company".

I figured that it was worth a sign.

 

[HueyPilotVN]

Update:

Some people just have to much time on their hands.

I thought that I was finished with the Solar Project. But I have come up with another addition to it.

I have figured out a way to add another 400 watts and 300 amp hours to the system.

I will still keep the configuration of using the 900 amp hour battery bank to supply power to the Invertor to feed the 110 volt AC system and I will also maintain the independence of the factory 12 volt system.

The original 12 volt circuits will still remain intact but will now be fed by an exact duplicate of one of the three systems that feed the back 900 amp hour battery bank.

I have freed up space by relocating the King Dome Dish satellite antenna and removing the over the air Winegard antenna from the forward area of the roof on the passenger side.

I have enough room to mount two of the exact same Rich 200 watt panels in this space. The King Dome will move to the empty area behind the air conditioner.

The cables will feed down into the cabinet over the sofa. The cabinet will hold the circuit breaker/fuses for the input and output for the Blue Sky charge controller. This is the same Blue Sky Master controller as the one in the back. It is also connected to an IPN battery monitor like in the back.
The front and back systems are completely independent.

Both the charge controller and the battery monitor will surface mount on the outside end of the cabinet by the entrance door.

The output 10 gauge cables and the twisted pair for the shunt will go down behind the sofa thru an enclosed chase.

A 300 amp hour Lithium battery will go under the sofa and replace the two AGMs that are currently under the steps,

In the current battery compartment, I will install two buss bars, one for positive and one for the negative cables.

The 2/0 cables will come up thru the floor to connect the buss bars to the battery. The negative cable will have the monitor shunt inserted in the circuit.

This battery will still be connected to the factory charger but will allow the panels to feed and top off the lithium battery. I may later disconnect and bypass the WFCO convertor charger with a higher output dedicated lithium charger.

This is a simple replacement of the factory 12 volt system power source with a system duplicating one of the three other systems feeding the “Bubba Edison’s Solar Electric Power Company”.

I will now have 1,600 watts of solar and 1,200 amp hours of battery capacity.

I may call the house system the “Baby Bubba System”.

I would post some picture of the components, but they are already in this thread.

 

[HueyPilotVN]

Another small project to finish off the Bubba Edison System.

I almost never experience cold weather.

However, I thought I would make sure that the Lithium batteries in the storage compartment would safely charge in the cold.

The front Lithium battery will be under the sofa inside.

I am running a Romex cable to an outlet in the back storage compartment with a switch in the bedroom. I ordered a small wattage space heater, (400 watts) to heat the compartment if needed.

I also used two pieces of the Lexan plastic from when I cut the extra off the Bubba cover.

I put industrial Velcro on the Lexan, and they are now winter covers for the ventilation grills on both side doors.

You can pull it off and store in on the other Velcro on the doors for Summer.

Without pictures it did not happen.

 

[jackiemac]

Good to see your enthusiasm for projects is back!

 

[HueyPilotVN]

Final Solar Update, (unless I find something to add to it).

I have just finished the installation of the new “Baby Bubba”, system.

This is a completely different and isolated system than the big system in the back. The back system has the sole purpose of suppling 110 volt A/C thru the Invertor to the main power distribution center which is normally powered by shore power or the generator.

The roof now has eight panels for 1,600 watts of solar feeding 1,200 amp hours of Lithium.

The front factory system has been replaced and still has the function of providing the DC power to the entire RV just like any normal RV.

The house batteries, (2 AGMs) were located under the steps. I installed as a replacement a 300 Amp hour Lithium, same as the back three.

To address the issue of charging in cold weather, I installed the Lithium battery inside and under the folding couch by rerouting the cables up thru the floor.

This system is charged by two sources. The factory convertor charger, and a new additional 400 watt panel pair feeding a copy of the Blue Sky Controller and Pro Monitor that is the same as the back system.

The cables from the solar panels feed down into an overhead cabinet by the door and directly above the new battery.

A circuit breaker/fuse protects the charge controller and allows for disconnecting the panel if needed.

The two Blue Sky devices are flush mounted on the outer right side of the cabinet.

The cables from the controller go down behind the side valence and are hidden from view.

Under the couch the negative cable has a shunt for the Pro Monitor, (Blue Skys version of the Victron Monitor).

I actually ordered a new WFCO power center that can recognize Lithium batteries.

I cancelled it and returned it because with the 400 watts to finish off the charging, I think that I do not need it.

Besides it is a lot of work to rewire the A/C and DC circuits.

Here are some pictures.

 

[HueyPilotVN]

After seeing several posts that recommend using a Class T fuse for the Invertor, I finally decided to go ahead and spend $90 for a fuse, I hope I do not blow it.

I guess it is not quite so bad when you consider the entire system cost over $12,000.

It is a 400 amp fuse replacing the 450 amp ANL fuse.

Here is a chart of the recommended size by Invertor size.

Without pictures it did not happen.

The last picture is of the ANL fuse I replaced.

I did have to bend the cable just a bit.

 

[HueyPilotVN]

I also got the Lithium charger board for the WFCO convertor/charger when I found out that you can replace the charger board without changing the entire unit.

Supposed to be only 5 wires and you do not have to rewire the other circuits.

I have it but have not started on it yet.

 

[Frank B]

So, Bill, when are we going to get a report on how long you can run your A/C? Should be warm enough down your way by now to run it.

 

[HueyPilotVN]

I have not run the full series of tests on the Bubba Edison Solar Electric Power Company, ( in the future I will just call it the Bubba System), to much typing.

I did however do a short test run the other day with temperatures of over 102 degrees.

I ran the system for 60 minutes with no outside electricity, (shore or generator). The compressor was engaged the entire time due to high temps. The inside temp was very comfortable, just like shore power.

I did have full sun and the charge controllers were putting out about 100 Amps DC into the battery bank.

The hour run reduced the SOC by 11 % from 100 to 89%.

I had turned off all other 110 volt systems except for the lithium convertor charger in the main panel for the front DC system. The refer, hot water heater, and security system were off.

 

[HueyPilotVN]

Here are some of my reflections on this project.

It was an interesting use of my time and kept me thinking of new revisions and upgrades during the project.

This is not a practical application from a financial standpoint but it was fun and educational.

The final cost with the last upgrades was close to $14,000 and the decision to order lots of extras and put together 10 smaller 400 watt systems to give away drove the total between $20,000 and $22,000.

There was another upside to this project in that I now have 24/7 availability of 120 volt AC electricity without outside electricity.

This means that such things as the refer, water heater, security systems with 8 cameras, microwave, and all three TVs can operate easily within the load factor.

I am also adding Starlink which requires 110 power. So I can leave it on all the time.

 

[Frank B]

I have not run the full series of tests on the Bubba Edison Solar Electric Power Company, ( in the future I will just call it the Bubba System), to much typing.

I did however do a short test run the other day with temperatures of over 102 degrees.

I ran the system for 60 minutes with no outside electricity, (shore or generator). The compressor was engaged the entire time due to high temps. The inside temp was very comfortable, just like shore power.

I did have full sun and the charge controllers were putting out about 100 Amps DC into the battery bank.

The hour run reduced the SOC by 11 % from 100 to 89%.

I had turned off all other 110 volt systems except for the lithium convertor charger in the main panel for the front DC system. The refer, hot water heater, and security system were off.

I will attach this update to the thread on the Bubba system.

Sounds good, Bill!

It does indeed take a LOT of power to run an air conditioner, and especially in those temperatures. While your system may be well beyond what the average guy would build, in a lot of cases a person only needs some air conditioning during peak hours. If I put lithium batteries in our unit, and increased the airflow around our inverter, I could probably run our air conditioner for a few hours at midday now. I have hit 60 amps from the controller in full sun in Alberta.

Which means that with the lower cost of residential solar panels, and the cost of storage going down, it is feasible these days to run an air conditioner off solar -- part time, at least.

And even if not AC, more panels and more storage means that even in marginal Sun conditions a person boondocking would never be without electrical conveniences.