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Enjoyed your videos on Solar very much. Thanks for sharing your knowledge. Purchasing a 40+ foot 5er. Question …… is it practical to build a solar system able to effectively run res fridge, TV & entertainment equipment, flush camode, pop some corn, etc, etc, not to mention run one of 2 or 3 heat pumps. Thinking generator will be required ….. comments welcomed, folks. Thanks. Pat
I’m not sure what a heat pump is but it is absolutely practical for the others. Keep in mind going solar will not immediately be cost-effective but it will immediately be independence-effective. Never expect to rely on solar for AC units or electrical heaters or anything that runs for hours with a heating device, like a water distiller. Also, the more you can know about your solar set up, I believe will save you in money instead of relying on someone else to tell you everything.
Hey Pippi, it is kind of hard to explain, but a heat pump is a self contained heating and cooling system that using the flow of the refrigerant to heat or cool. Looking at it like a clock, if the refrigerant is flowing clockwise the system is cooling. Inside the unit there is a reversing valve that when activated changes the flow of refrigerant to counter clockwise which makes the system heat instead of cool. They are great for warmer climates, but really aren’t too practical for colder climates because without a helper heater they aren’t able to generate heat when the temp dips below the high 30’s.
I’ve noticed that in recent years that a lot of the upper end RV’s come with heat pump heat/cooling systems.
My understanding…
Heat pumps draw heat from the environment instead of using traditional methods to create heat. They use slightly less power (or so I am told) than traditional heating systems. The downside is that they are only useful/effective down to a certain temperature. For probably most users, they would be adequate for early or late season camping where the temps won’t fall below 40.
As to power consumption, a heat pump will probably be too power hungry to run off a solar system. Unless that is, you size the solar system properly. I’m kind of thinking that the system would have to be too large to make it practical for an RV. You’ll probably have to supplement your solar system with a genset.
As to how they work, I’m no expert but I guess a reasonably simple version would be to look at how your refrigerator works when you run it on gas. Then reverse the process from creating cold to creating heat.
The HVAC guys and gals out there will probably take issue with that explanation, but for a layman like me, it’s close enough.
Good luck and please let us know what you decide for your solution.
Pat, its impractical for long term dry camping to power a “relatively large” residential 120 VAC Compressor type of fridge (NOT an LP Gas Ammonia Absorption) using Solar. Sure, its “possible” if you have a huge battery bank, a ton of solar panels plus are exposed to good sunlight for long time periods. I have a very small dorm room size Haier 120 VAC compressor fridge I run 24/7 but also 450 battery Amp Hours (Four Trojan T-105’s) and 470 solar watts. Of course, it all depends on the size of the fridge, your solar wattage, total battery amp Hours and sunlight. I cant provide any details not knowing more about the fridge and all the other variables, but 400 to 500 battery Amp Hours and maybe 500 or so solar watts is at least a starting point but likely NOT enough if its a large residential size fridge.
John T Retired Electrical Engineer in Indiana
Pat, I always read these solar discussions out of curiosity.
I’m not against solar, it’s just that our camping style doesn’t require solar power as a high priority. For us, a rooftop solar installation of solid panels (not flexible panels) has at least these two downsides:
1. I prefer and need pretty full access to our RV’s roof from the roof (ladders propped against the sides won’t do) without having to step around, and/or do a balancing act around, the solar panels to get to the A/C, the roof vents, and the TV antenna.
2. I will not tolerate holes drilled into our one piece fiberglass roof. Holes into it would just be more opportunities for leaks without periodic inspection and maintenance of each penetration spot … and how are you going to doing this while stepping around, and/or do a balancing act around, the solar panels?
However in all fairness, there ways to glue down the solar panel mounting brackets to a fiberglass or aluminum roof – if you want to trust the adhesive year after year of being exposed to the elements.So I wanted to know how are you dealing with such things? Do you have a video about your inspections?
Back to the topic, IMHO, adequate high power generator capability should always be the primary electrical energy source – and solar capability the secondary electrical energy source – in any RV considered as being fully self-contained for extended non-hookup camping.
We don’t have solar power at all in our small Class C motor home. But we do have the built-in Onan generator, carry along an extremely quiet (54dB noise level at full power) portable Honda generator, and can also idle the very quiet and vibration-free main engine in areas that are extremely noise sensitive.
The weather is just too unpredictable for most RV’s to not have along some kind of a generator along on all trips. Especially if you’re going to run so many devices at time.Just a small warning from our experience and two coins. No offense!
– derek (+ mary)
Pat, the advice here is pretty accurate. However, you can do anything with unlimited funds.
Practical is subjective, but our solar system is 1000w with a 900AH battery bank (450ah usable).
Our panels only line one side of our RV so no balancing act required to service anything on the roof.
That being said, we still don’t/can’t run our heat pumps/AC units off this system because of the battery type (SLA).
However, we do run everything else. That’s coffee maker, 2 x TVs, microwave, all lights, water pump, furnace, fantastic fans, ceiling fans, stereo, 2 x refrigerators, etc.
We use propane for the furnace, water heater and fridge. We have 2 refrigerators. 1 is a 120v compressor style for drinks, and the other is an 18cuft LP/AC style.
We only use the generator to run our ACs in the summer if needed, however, we typically move to Colorado for the summer where AC is not required.
So yes, it’s possible/feasible/practical with limitations like funds or willing to accept something’s can’t be used like heat pump/AC.
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