Solar Power: Myth?

[ROUX DOG]

Are solar panels a real source of hardcore, measurable, dependable energy or is it just another expense that allowing one to have "warm woollies" regarding the environment?

[1Mdriver]

I am new to the Airstream world but have over a decade of solar industry experience.

Utility scale solar plants now produce the cheapest source of power across most of the globe (high wind areas being the exception). The problem with solar is it only produces power when it is sunny.

With energy storage (batteries) and good sun exposure, it is now reasonably practical for some folks to go completely off grid for smaller houses. However, hooking up to a utility with solar (parallel generation) is the most cost effective way to go solar.

For an Airstream (and small solar systems in general), you pay a premium per kWh generated as the equipment is fairly specialized (and not produced or sold in high volume) and typically not oriented for optimal sun exposure (tilt and direction of solar panels is important). Additionally, in order to “comfortably” power an airstream from solar only, I would imagine you would need 3-5x the battery capacity and solar typically provided by Airstream. This would allow you to “weather” rainy days and not compromise you usage (AC etc). Problem is that batteries are heavy and solar panels need space so you would eat into your payload.

[Rocinante]

Well, we had 650 watts of solar on the roof of our Airstream, and 400Ah of Lithium batteries. The system generated plenty of power for any kind of dry camping we'd ever want to do. The only thing that ever forced us to leave our campsite was a need for more fresh water or to dump our waste water tanks. We were happy about that. Also, because of that solar / lithium upgrade, we were able to sell our Airstream at a very good price less than two weeks after listing it on Airstream Classifieds. We were happy about that, too.

We also have 11.5KW of solar panels on our house. We regularly generate well over 100% of our daily power needs, and currently push the excess energy to the grid. Soon, we'll have a large bank of lithium batteries, which we will charge via our solar panels and use as a power source overnight and whenever there's a power outage. We're happy about that, too.

So, I don't need to wonder about solar power, but you go right ahead, if you like.

[DaveP]

I have 400 watts of portable solar panels with an MPPT 100/30 controller. It works. I have not used a generator in five 4-day trips this season.

[Rocinante]

Originally Posted by DaveP

I have 400 watts of portable solar panels with an MPPT 100/30 controller. It works. I have not used a generator in five 4-day trips this season.

Ah, excellent point. We still have a 2000 watt Honda generator that we used before upgrading our RV's electrical system as noted above. After that upgrade, we just left the generator at home. Once we get our lithium battery bank installed here at home, we'll either sell it locally or donate it to a charitable organization that needs one, because we'll no longer have any use for it.

[HappyHapgood]

We like not having to carry a generator. We like not having to hook up and start a generator.

Yes, sometimes we have to be economical with our electric usage, but same goes for water.

If I wanted to deal with a generator and not bother being careful with water and electricity I’d probably buy a big motor home.

We have 800 watts solar and 600 kWh of lithium batteries. It’s a system that we monitor but otherwise don’t have to mess with at all. It just works.

[1Mdriver]

Originally Posted by Rocinante

Well, we had 650 watts of solar on the roof of our Airstream, and 400Ah of Lithium batteries. The system generated plenty of power for any kind of dry camping we'd ever want to do. The only thing that ever forced us to leave our campsite was a need for more fresh water or to dump our waste water tanks. We were happy about that. Also, because of that solar / lithium upgrade, we were able to sell our Airstream at a very good price less than two weeks after listing it on Airstream Classifieds. We were happy about that, too.

We also have 11.5KW of solar panels on our house. We regularly generate well over 100% of our daily power needs, and currently push the excess energy to the grid. Soon, we'll have a large bank of lithium batteries, which we will charge via our solar panels and use as a power source overnight and whenever there's a power outage. We're happy about that, too.

So, I don't need to wonder about solar power, but you go right ahead, if you like.

.

Awesome to hear about your two systems! I have personally developed nearly 700 MW of in solar projects (>$1 Billion worth) across the United States. With your Airstream system how long can you run full out (AC, fridge, tv, microwave) without recharging? 10 hours or so? I know that’s not a real use case scenario but just curious. I would love the ability to have an Airstream with approximately 1440Ah of batteries plus 1200W of solar (3x 400W 72 cell modules bolted to the top) as it would be nearly unstoppable during a power outage/emergency situation or for boon docking (minus the water issue). Also, the funny thing is that the solar would only cost $500 if you can find a way to attach regular modules to the roof.

[Rocinante]

Originally Posted by 1Mdriver

.

Awesome to hear about your two systems! I have personally developed nearly 700 MW of in solar projects (>$1 Billion worth) across the United States. With your Airstream system how long can you run full out (AC, fridge, tv, microwave) without recharging? 10 hours or so? I know that’s not a real use case scenario but just curious. I would love the ability to have an Airstream with approximately 1440Ah of batteries plus 1200W of solar (3x 400W 72 cell modules bolted to the top) as it would be nearly unstoppable during a power outage/emergency situation or for boon docking (minus the water issue). Also, the funny thing is that the solar would only cost $500 if you can find a way to attach regular modules to the roof.

Very impressive, that's a lot of solar to have brought online! With a full charge, we can run the Dometic air conditioner on batteries alone for several hours, though I have to admit we've never done that on purpose. Given the trailer has a 3K watt hybrid inverter / charger, we could run both the AC and the microwave at the same time off the batteries, if we wanted to. One of the more entertaining scenarios we've enjoyed is plugging into 15-amp power in a friend's driveway and running the air conditioner indefinitely on a combination of power from the 15-amp source, the batteries, and our solar panels...without popping a single breaker.

Funny story, we had our trailer in for service at Colonial Airstream (a great place for Airstream service, btw) and they forgot to plug in our trailer while working inside. They were running the AC and working away, when at one point the "Low battery" alarm we had set to go off at 20% of charge started complaining. They stuck their heads out and asked us what the alarm was about. After a quick look, I said, "Well, it looks like you never plugged in the trailer. How about you check that?" Sure enough, they had forgotten. So they plugged it in, the batteries began charging, the AC kept right on running, and they got back to work.

Oh, and one more story: After installing this solar / battery system, we always ran the fridge on A/C power instead of on propane while moving down the road. We had so much solar influx, that when combined with power from the truck's alternator, we had no trouble arriving at most destinations with fully charged coach batteries. The wife loved this, because she had always hated running the fridge on propane while traveling. She just felt safer this way, and I was very pleased that as one of the many benefits of this upgrade, we were able to set her mind at greater ease as we traveled down the road, even though it wasn't a potential benefit we considered when we did the upgrade.

[SuperTrouper]

Hey Roux Dog, we only have 400 watts of solar and 220 AH of AGM battery but that allows us to camp most anywhere with sun and not use a generator. We still have a Genny but rarely use it (only in dark forest locations or if we need the A/C) and the batteries stay charged even while in storage so they last 7-10 years. I wholly endorse solar if you get it installed right with correct size of wire and quality components. The AS factory solar Wiring is not optimal. - Brad

[gator.bigfoot]

I've got 300 watts of solar and never plug in my trailer to charge. There is 420 AH of storage (AGM). I don't own a generator. Everything 12v runs off of solar and has for years. Don't need a microwave or any of the other appliances. Fridge and hot water run on propane. Usage is negligible. The Bbq uses more. Very inexpensive system. Sure you can go bigger, but why? This is camping. I don't live in it full time. I can use the TV the stereo if I want, but rarely do. The cooling fans run most of the day. Pretty much every day the charge was back at 100%. Some really cloudy or rainy days it got back to 98%.

After a recent camping experience where there were non stop generators around me, I don't ever want to hear one again. There was only a couple of guys using solar but the rest in the park all had generators. What a miserable experience.

[ghaynes755]

1MDriver, you would be hard pressed to put 400W panels on the roof of an Airstream, just not that much open space that doesn't have vents, fans, air conditioners, antennas and other such stuff sticking up.


Would like to know where you could get solar system components for 3x400 panels, solar controller, wiring for $500.

[Dennis C]

Is the Airstream optional 180W rooftop solar system with AGM batteries acceptable for an average weekend camping trip? I realize that power consumption varies based on your camping style and your electrical needs and this will obviously be a major factor in determining what is acceptable or not. My wife and I are about to purchase our first Airstream (International Serenity 23FB) and it's equipped with the 180W rooftop system. We prefer to cook/grill out, and we aren't big TV watchers.

I would really rather not buy a generator if I can avoid it. I'm fine without using the television or microwave when I'm not connected to shore power. I worry a little bit about not using the air conditioner in the warmer months, but most of our camping will be in the mountains and it doesn't worry me too much.

After reading this thread, I'm wondering if I should consider adding additional solar capabilities.

[AdvToaster]

I’ve got 600W of solar and 630Ah of lithium. I don’t own a generator. When we boondock we don’t worry about power usage at all, unless we run the A/C.

TVs, fans, and microwave all get used while we’re off grid. I also have a computer running 24/7 with multiple hard drives that handles our media and backups.

[Dennis C]

Originally Posted by AdvToaster

I’ve got 600W of solar and 630Ah of lithium. I don’t own a generator. When we boondock we don’t worry about power usage at all, unless we run the A/C.

TVs, fans, and microwave all get used while we’re off grid. I also have a computer running 24/7 with multiple hard drives that handles our media and backups.

That sounds great. Are your solar panels mounted to the roof of your Airstream, or do you plug them in when you arrive at your campground?

[AdvToaster]

Originally Posted by Dennis C

That sounds great. Are your solar panels mounted to the roof of your Airstream, or do you plug them in when you arrive at your campground?

Roof mounted. They help my 60A Renogy DC/DC charger keep the batteries up while we drive with the A/C running. The trailer never gets above 80 inside.

I do plan to add two more panels so I can change from a strictly parallel wiring setup to paralleled series pairs. This will increase the voltages, allowing the charger to start up earlier in the morning and run later into the evening, as well as of course supply an additional 200 theoretical watts.

[ASFC25_2019]

Originally Posted by AdvToaster

Roof mounted. They help my 60A Renogy DC/DC charger keep the batteries up while we drive with the A/C running. The trailer never gets above 80 inside.



I do plan to add two more panels so I can change from a strictly parallel wiring setup to paralleled series pairs. This will increase the voltages, allowing the charger to start up earlier in the morning and run later into the evening, as well as of course supply an additional 200 theoretical watts.

That is an amazing set up. What size of A/C unit do you run? And how long can it run for on battery power no solar. How many Ah do you normally get each day?

[1Mdriver]

Originally Posted by ghaynes755

1MDriver, you would be hard pressed to put 400W panels on the roof of an Airstream, just not that much open space that doesn't have vents, fans, air conditioners, antennas and other such stuff sticking up.


Would like to know where you could get solar system components for 3x400 panels, solar controller, wiring for $500.

Just Google “Canadian Solar 400 W module for sale.” Going rate from online retailers is in the $0.45-$0.55/W range so about $200 per panel. Real industry/direct from manufacturer cost is much closer to $140 per panel. Note my quote did not include a charge controller or inverter but PVwire is cheap. The “gold standard” in residential inverters is a SMA Sunny Boy is about $1200 per 5kW unit so I would expect a good DC charge controller with MPPT to be substantial cheaper.

As far as space goes, each 72 (or 144 1/2 cell) panel is about the same size as an interior residential door (~8x3 ft) so I could be possible to fit them if you could avoid other roof top equipment.

[stevejones]

We have 700 watts solar, 600AH of lithium batteries, and a 3000W inverter. We can run anything we want and don't need to worry about battery power. We could run the AC for three hours or so if we wanted to, but carry a propane converted generator if we want AC when we don't have shore power.

Obviously sunlight is a factor. If we're in cloudy weather or in the shade we just manage how much we use. The panels still charge, just not as much power comes in.

Solar is definitely a real source of hardcore, measurable, dependable energy.

Steve

[rowiebowie]

Originally Posted by Rocinante

Once we get our lithium battery bank installed here at home, we'll either sell it locally or donate it to a charitable organization that needs one, because we'll no longer have any use for it.

Hurricanes?

[GMFL]

Solar is definitely not a MYTH if installed correctly.