use of "plug and play" solar for temporary use

[Herschel]

I have started thinking about a lazy, lengthy boat trip next spring around Florida. Down the St, Johns from Sanford; Atlantic ICW to Okeechobee Waterway; to Gulf ICW; to St. Pete. To help with food storage, I started thinking about 12v/110v coolers that I can use both in the boat and in my travel trailer. Here is one just as an example.

Then I ran across these power stations with accompanying solar like this:

I realize the whole world of boating is quickly moving toward permanently installed solar, but my wife and I are just not all that interested in anchoring out (e.g., CPAP, age, "fuddy duddy" factors). We prefer marinas and even motels when available, but food storage requires either regular ice refills or power of some sort. Not terribly interested in a gas generator, either. I am wondering if anyone has experience with these portable power stations with "plug in" solar so you don't have do do permanent systems aboard?

[Tomfoolery]

I haven't given solar enough thought to form a real opinion yet, other than the compressor fridge/freezer is definitely the way to go. About 50W when the compressor is running, or about 4 A at 12.5 V. That's about 48 Ah/day if running half the time. A couple of deep-cycle batteries should handle that ok without dropping the charge too much, and that can be mitigated with a solar panel or two. Fully recharged overnight when in a marina, of course.

My 200 W of solar can keep up with the daily use of my RV's much larger fridge/freezer even in cloudy weather, and that was before I figured out (and corrected) that one of the three panels was never connected by the upfitter (Coachmen ) - it's supposed to be 300W (3 x 100W). It puts out about 16 A now, with all three panels working, at solar noon on a clear day, way up here. Should be able to do a bit better down where you are, with the sun more directly overhead.

Might be better off just using the house batts and a single panel, which may or may not even need a solar controller. Those fridges all seem to run on 12 VDC (and 120 VAC), so no worries there about having an inverter.

[BOAT]

Funny this came up - i just bought an umbilical that goes from the Van solar system to the boat and that Vans system keeps the batteries maintained on both the van and the boat while they are parked in the driveway.

I also have a portable solar panel inside the windshield that keeps the van truck battery topped off and I just go an umbilical for that unit YESTERDAY! I hooked it up last night and was just getting ready to go out to the driveway to check the charge on the boat battery when I read this post!!

The idea is that I could use the portable unit in the van windshield to charge the batteries on the boat when I am on the water!

Good timing!

[Herschel]

Tom and Boat,
Great info. Perhaps the first step is to get a cooler and see how the house batteries handle it. My battery bank of Optimum "deep cycles" is about four years old, so I want to pursue the power station as well, partly to break into the solar world. I don't want to hook up solar panels to my battery bank and cook them because I don't wire in a controller. I watch a ton of YouTube sailors installing battery banks and solar panels with controllers and associated circuits, and it all seems a little intimidating for an old salt like me in my "dotage". The details of amp usage for your coolers is good because the power stations come in a wide variety of sizes from about 100 to 1000 watts. If I go ahead with a power station, what size would you techies recommend for the average 12/110 volt portable frig? But, then there are the laptops/tablets/phones that will spy the power station and demand "facetime"! Its kind of like shopping for a new car; "nice to haves" become necessities pretty fast.

[Russ]

I have an Edgestar 48q compressor cooler. It will run off my single house deep cycle all day. I supplement with an 80w solar panel that gets me a few days if careful.
Solar is NEVER 80w as that is ideal circumstances.

[BOAT]

The portable has the controller built in so it will never fry the battery. I have this 60 watt unit and it really puts out a lot even in the shade. I am surprised by how well it does.

https://www.amazon.com/gp/product/B07ZZ ... UTF8&psc=1

You can get one that is larger, (I see them up to 220 watts!) but like Russ said it's not enough to run the fridge because the panel does not work at night. You could have 1000 watts of solar but your battery will still go dead during the night because the panels are not charging anything in the dark no matter how big they are.

So, the issue is not your panel - it's your BATTERY.

If you can get a battery big enough to last all night on a charge AND a panel big enough to give that battery a full charge every day you can have a reefer 24/7.

Your Amazon cooler did not list the amp draw (right off the bat I would not trust a unit that does not display the amp draw) but if the draw was 4 amps you would need about 125watts of battery power (Tom can tighten those calcs) or that means about a battery and a half.

Can you add more battery power? If you can then about 130 watts of solar should do it. They do make portable solar panels that size and remember - the portable ones have the controller built in so no fried batteries.

[Tomfoolery]

So, the issue is not your panel - it's your BATTERY.

If you can get a battery big enough to last all night on a charge AND a panel big enough to give that battery a full charge every day you can have a reefer 24/7.

Herschel's stated operating conditions (see below) are marinas at night, presumably with shore power, and sailing/motoring all day. So given those parameters, the batteries only need to power the fridge during the day, with that load offset by whatever a solar panel or two can output to the system, minus whatever other loads are applied (nav system, autohelm, radio, etc). That can result in rather small demands on the batteries during the day, depending on sun and solar panel capability, and negative demand at night (shore power charging).

BUT, if overnighting without shore power for any reason, then it's back to battery capacity during the overnight. Which is why I agree that extra battery capacity would be wise. They can always run the OB to help recharge the batteries, assuming it has something approaching real alternator output (unlike my Honda BF50 ), but it certainly would be best to allow for at least a full 24 hrs without shore power, and some 'extra' solar just in case. But at least solar can be added bit by bit with time, with the right setup from the start.

And it would be important to know just how much energy that fridge/freezer actually draws, once down to operating temperature with a full load of stuff inside, over a 24 hour period on the boat (hot down there during the day in FL), since I would expect it to cycle and not run continuously, especially at night.

. . . my wife and I are just not all that interested in anchoring out (e.g., CPAP, age, "fuddy duddy" factors). We prefer marinas and even motels when available, but food storage requires either regular ice refills or power of some sort.

Edit: Re-reading what I just posted, it looks like I'm in agreement with your conclusions, BOAT, if for slightly different reasons.

[BOAT]

Yeah Tom, you got all that stuff right.

His thing is that he does not want to install a big system and he does not want to go to school for two years or get a degree in electrical engineering. I get where he is coming from.

That's why the portable solar panel is the key: the portable ones come with the controller installed.

He just wants some one to tell him [this size portable panel] and [this size battery] will keep [this size reefer] going 24/7

That's why I'm concerned about his choice of reefer.

He needs to spend his money on the most efficient reefer he can find or he will be draining the battery every day and ruin it and then all his solar power is a waste. Solar panels will not charge fried batteries much.

We need that missing part of the equation: [this size reefer]

If he can give us the missing reefer draw I thought you could calculate the other two parameters. I was just offering my best guess:

[130WATT PANEL] and [125WH BATTERY] will keep [4AMP/12V REEFER] going 24/7

That might not be enough power for a 4 amp load that occurs only 10 minutes per hour but it should be pretty close.

What do your calculations say? Your better at the numbers than I am.

[Tomfoolery]

He just wants some one to tell him [this size portable panel] and [this size battery] will keep [this size reefer] going 24/7

That's why I'm concerned about his choice of reefer.

He needs to spend his money on the most efficient reefer he can find or he will be draining the battery every day and ruin it and then all his solar power is a waste. Solar panels will not charge fried batteries much.

We need that missing part of the equation: [this size reefer]

If he can give us the missing reefer draw I thought you could calculate the other two parameters. I was just offering my best guess:

[130WATT PANEL] and [125WH BATTERY] will keep [4AMP/12V REEFER] going 24/7

That might not be enough power for a 4 amp load that occurs only 10 minutes per hour but it should be pretty close.

What do your calculations say? Your better at the numbers than I am.

Nice use of color.

I just checked my van (solar noon), and I'm getting 3.3A out of three 100W solar panels with heavily overcast skies. I get 16A at this time of day with clear skies, but I am way up north where the sun don't shine so good even on a good day. Could be worse - could be northern Canada or Alaska, I suppose.

Anyway, you're absolutely right in that you need to know what the load is before you can estimate what you need to drive that load reliably. That's why I think they need to source and actually test run the unit while recording power draw over a 24 hour (or some multiple of that) period.

That power station he linked to only has 24Ah capacity, while the typical deep-cycle marine battery at 90Ah is probably good to 45Ah without discharging too far. That's about how much that small fridge/freezer will use in 24 hours (estimated) based on 50% run time. But the power station should be able to run it during the day with no augmentation, since you can pull lithium batts down to something less than 10%. My van's LiFePO4 system shuts it down at 4%, which I just did the other day before charging it back up, per the manufacturer's recommendation for long-term storage (brought back to 50% after that for actual storage).

And the solar panel can be plugged directly in, so no external charge controller needed. But I think it's an expensive way to do it, being that there are already batteries on the boat.

Oh, and excuse us for talking around you, Herschel. Just tossing some thoughts around. Wish Sumner were here - he's done a lot of this solar work on his boats. Highlander, too. And some others who's names escape me at the moment.

[BOAT]

Yeah, sorry Herschel - I know your there, I just do not usually give advice on electrical things here without Tom or Sumner or some one who's more knowledgeable in the back ground so that's why I was addressing him so much.

So the generator thing is sort of hard to say.. Really, that generator is just a Lithium Battery.

It says 500 Amp Hour at 120 Volt - so that means at 12 Volt it's only 50 Amp Hours.

So what's the cost of a 12 volt 50 Amp Hour Lithium Battery??? I dunno but my 100 Amp Hour Battle born Lithium batteries were 800 each.

So - it's $800 for 100 Amps or $500 for 50 Amps - like Tom said - it's hard to say which is best.

If you did it by the amp the Generator is $10 per amp and the battery is $8 per amp.

Maybe Tom can comment.

[Highlander]

mobile fridge / freezer has zero reviews so I would pass it by until I see a lot of positive comments

J

[Herschel]

OK, guys. Sorry to be AWOL today. Was actually out on my boat for a quick loop around Lake Monroe until the proverbial summer thunderstorm drove me back to the marina. I found a similar cooler and got some amp hour data for this unit (which was ranked #1 by some outfit) from a purchaser who listed his experience with power usage on his sailboat under the Q&A section.

Here is the data on power usage from an anonymous buyer: "I think on initial startup when it is cooling from 80 degrees down to 30 or 35 I see about 4 amps of draw. Maybe slightly higher. In an ambient temperature environment of 75 degrees, it will run about 30% of the time. On the Eco setting that is about 2.4 amps, so divided that in 3rds and you will get your hourly consumption. I would bet on 20 to 25 amp hours / 24 hour period. I just installed mine on my sailboat last week. I am using a 100 watt flexible solar panel and my batteries are topped off after just three hours of sunlight in the morning. My panel can produce about 5 and 1/2 amps"

So, say this is my new cooler/frig. If I got one of the Power stations, say the 500 watt one, I am essentially getting another "deep cycle" type battery, a lithium one, with a built-in controller for the solar and an inverter for possible 110 applications (read coffee pot). Right? But I will be paying more for the power I get through the Power Station because it is more expensive than a regular deep cycle battery (my Optimas are a bit pricy, but I really swear by them. Very long lasting and reliable). If I stay in marinas at night and do a fair amount of motoring during the day (50 h.p. Yamaha with alternator), my present battery bank can handle this cooler. But, if I wanted to "play around" with a portable solar system, the Power Station with solar could be a separate system from my boat battery banks, but I am drifting into the realm of buying a toy, not a practical or needed nautical system. Right? One more question. I am still curious about how to break into solar technology without the engineering degree. Do solar panels come with their own controller so you can just plug the wires into your house battery safely?

[Russ]

You need to realize the fridge isn't going to run 24/day. Mine cycles about 25% running time. Then you could insulate it a bit better.
We get it real cold and turn it off at night because we don't like the sound of the fan/motor.

It's really nice to have food cold and not wet from melted ice.

[Tomfoolery]

Here is the data on power usage from an anonymous buyer: "I think on initial startup when it is cooling from 80 degrees down to 30 or 35 I see about 4 amps of draw. Maybe slightly higher. In an ambient temperature environment of 75 degrees, it will run about 30% of the time. On the Eco setting that is about 2.4 amps, so divided that in 3rds and you will get your hourly consumption. I would bet on 20 to 25 amp hours / 24 hour period. I just installed mine on my sailboat last week. I am using a 100 watt flexible solar panel and my batteries are topped off after just three hours of sunlight in the morning. My panel can produce about 5 and 1/2 amps"

That solar output sounds about right, from what little I know of my own 300W system (3 x 100W). And that power usage rate sounds about right, too, also based on my own much larger Norcold AC/DC two-door top freezer unit at 5-6A DC running.

So, say this is my new cooler/frig. If I got one of the Power stations, say the 500 watt one, I am essentially getting another "deep cycle" type battery, a lithium one, with a built-in controller for the solar and an inverter for possible 110 applications (read coffee pot). Right?

Right. Sort of. Forget the coffee pot, though, as it'll suck all the energy out of a Power Station unit, and probably exceed the max power output anyway. Coffee makers are usually around 1000W or so. Anything designed primarily to make heat is, as a general rule, very energy intensive. Like blow dryers, and cooking appliances, and so on. Better to use a portable propane or butane or alcohol stove to heat water and pour through a cone for coffee. I have a really nice little single-burner butane stove in a plastic carry case that's used just to boil water to pour through my Melita single-cup coffee cone. I think I paid about $14 for it a couple of years ago. Looks like this, but came with a case. Just sayin'.

https://www.hotelrestaurantsupply.com/WNC-PGS-1K.html

But I will be paying more for the power I get through the Power Station because it is more expensive than a regular deep cycle battery (my Optimas are a bit pricy, but I really swear by them. Very long lasting and reliable).

You have to compare the Ah rating of each system, modified by how deeply you can discharge them. Lithiums can be depleted almost all the way without harm, and they can maintain output voltage almost all the way down to fully discharged. Other chemistries, not so much. Lead acid is the least able to deep-discharge without harm unless you get into true deep-cycle batts, like 6V golf cart and forklift batteries. But as a general rule, you can get the same useful energy out of a much smaller (in Ah rating) LiFePO4 battery than you can out of lead acid, with other chemistries somewhere in between.

Big Caveat: You have to use a charge controller specifically designed for the battery chemistry you're charging. Lithiums charge differently, and at different voltages, than lead acid which is different from AGM and so on. And there are different types of charge controllers, for that matter, with PWM types being cheapest (Pulse Width Modulated, which means it's simply switching on and off rapidly to control effective voltage), and MPPT (Maximum Power Point Tracking) types, which adjusts both voltage and current to best match the solar panel output to the battery charging requirements, and adjusts itself as clouds go by and things like that. They're the best controller type, but probably unnecessary for a single 100W panel, and far more expensive than simple PWM types.

If I stay in marinas at night and do a fair amount of motoring during the day (50 h.p. Yamaha with alternator), my present battery bank can handle this cooler. But, if I wanted to "play around" with a portable solar system, the Power Station with solar could be a separate system from my boat battery banks, but I am drifting into the realm of buying a toy, not a practical or needed nautical system. Right?

Probably. I think, from what little I know about solar, that you could be well served just adding a solar panel and charge controller to your existing battery bank. Unless you need the inverter, too. In which case, the cost starts adding up. Probably should run a spreadsheet with costs for doing it both ways to at least see the cost difference. That has to be balanced against the convenience of each system, and the intended use, like taking it off the boat to use elsewhere.

One more question. I am still curious about how to break into solar technology without the engineering degree. Do solar panels come with their own controller so you can just plug the wires into your house battery safely?

Normally, no. You need a controller (see above), but I've seen some on Amazon that come as a kit of sorts, with 100W panel and separate controller.

Little panels for just maintaining lead acid batteries during down times can be used without a controller, from what I understand, but you need real power here, so a controller is needed. Except for those lithium power units, which have the controller built in.

[BOAT]

Do solar panels come with their own controller so you can just plug the wires into your house battery safely?

For a regular battery, yes.
Like this DOKIO unit at 200 watts:

https://www.amazon.com/DOKIO-Foldable-M ... s9dHJ1ZQ==


PWM charge controller already included.

This unit would be enough to run the reefer in my van 24/7 with only one 100AH Lithium Battery.

My reefer fires up at 5 Amps, is 31 degrees in less than 10 minutes. After that it only runs once an hour for about 3-4 minutes. If I set it to the nite setting it uses 2.4 Amps instead of 5 (really, the nite setting is just to make it silent because it uses nearly no power at nite anyways). If it's not over 85 in the van the I can use nite setting 24/7. My unit is a little smaller than Toms.

That's why I asked about the reefer - a really RIGHT insulated RIGHT ventilated reefer will use very little power. The main thing to spend your money on is the cooler - not the solar system.

The Battle Born batteries have under/over charge protection and temperature all built in. But, as Tom said - for Lithium you need higher voltage - 14.6 volts. I know you like your gel battery so the 200 watt panel mentioned above would charge it with no frying.

I will never go back to gel after having the Battle Born batteries - they are HALF THE WEIGHT! and last 20 times longer.

I am still on a Polar Bear in 'boat' with melted ice like Russ hates. I will convert to a cooler but still can't find a reefer with the specs I want. I had to have my van reefer imported because I could not find one domestically with the specs it had. It uses very little power and gets as cold as you want.

If I can find a drop in with good specs I will install it on 'boat'.

The thing about solar is you need to treat it as a DC system. Doing anything in AC power on solar is really bad. I do not even have the inverter hooked up in my van - it's just a huge drag on the system and converting DC to 120v AC sucks the life out of everything and ruins ALL of your equipment. It's there if I want it - all I need to do is connect the huge red cable to the lug in the back of the inverter and I told myself the first time I need some AC power I will hook it up but you know what? I never have because I don't need no stinkin AC power. (HA! )

I got a coffee maker that goes on the stove that works just as well as an electric one. (And NO, it's not a PERCOLATOR - it's a REAL coffee maker! so THERE!)