We all dread the electric bill. Every month, it's the same appliances draining the life out of our wallet. There's no doubt about it, heating and cooling are the biggest offenders.
While hovering over your thermostat and keeping that fridge door closed does help, these efforts usually pay little dividends in the end. In order to effectively take energy costs into your own hands, self sustainability is the best option.
Below we've outlined the 7 best solar refrigerator and freezers of 2021. We've also included a detailed guide for choosing, installing and using a solar powered refrigerator/freezer to get optimal results.
Keep in mind, we are not solar experts! We built this hub to steer you in the direction of the experts and to recommend low-energy consuming refrigerators that have worked well for other solar enthusiasts.
Enjoy!
Top Rated Products |
|---|
1) ACOPOWER AC/DC Powered Portable Cooler (ACOPOWER) - Best Portable Solar Cooler |
2) SMAD 2.5 Cu Ft Solar DC Fridge (Amazon) - Best Solar Chest Freezer |
3) Sundanzer 1.8 Cu Ft Solar DC Chest Freezer (Amazon) - Best Solar Chest Freezer |
4) EdgeStar 3.1 Cu Ft Efficient AC Powered Fridge (Amazon) - Best A/C Powered Mini Fridge |
5) Insignia 10.5 Cu Ft Efficient AC Powered House Fridge (Best Buy) - Best A/C Powered House Fridge |
6) Unique 6 Cu Ft DC Powered House Fridge (Home Depot) - Best Small-Sized D/C Powered House Fridge |
7) Unique 10.3 Cu Ft DC Powered House Fridge (Home Depot) - Best Mid-Sized D/C Powered House Fridge |
Best Solar Refrigerators
1) ACOPOWER R40A Portable Solar Fridge Freezer
I'd ask you to consider the possibility of having a portable fridge. Something you can take to the beach, camping, sporting events, fishing, or anywhere for that matter.
Immediately, most of us have a few thoughts:
- It'll be too heavy.
- It'll require a huge battery.
- It'll be too expensive.
ACOpower (a specialty solar panel company) took it upon themselves to create a battery powered refrigerator/freezer that would defy the limits we set on coolers. Let's look at why this electric cooler has received such positive feedback in such a short amount of time.
1) The ACOpower portable fridge is powered by a rechargeable lithium battery. This battery can charge via 12V (DC) car port, regular 110V AC outlet, or solar panel.
2) Has a temperature range between 14-43F (-10-6C) approximately.
3) Can remain at 32F for 10-15 hours with a full charge.
4) Fully charges within 4-5 hours with 12V car port or AC outlet (Solar panel charge-time will vary with solar panel and sun exposure).
5) Has digital temperature display, controlled directly on panel or through bluetooth.
6) Comes in 3 different sizes to accommodate storage needs (30, 40 and 50L Options).
I think it's important to mention how stellar the customer reviews are regarding ACOpower's customer service. It's a breath of fresh air to find a specialized company who truly takes care of their customers.
Our rating:
4.5 / 5 Stars
Pros
Cons
2) Smad 2.5 Cu.ft Solar Energy DC Freezer
For a lot of us, chest freezers aren't just a luxury, they're an absolute necessity. As a regular "buy in bulk" advocate, the extra freezer space is critical for keeping my food nutritious and fresh for as long as possible.
But as most of us know, heating and cooling are two of the biggest offenders on the electric bill.
So, what do we do?
Go solar of course
The Smad Solar Powered Chest Freezer/Fridge combo was designed to make the switch to solar as smooth as possible. Although it includes no solar equipment, it is tailored to fit a solar system seamlessly.
Equipped with a DC voltage system, this chest freezer can run off your typical solar panel to DC battery configuration. It also comes with an AC converter if you've already made the upgrade to an AC voltage system.
If this language is absolute gibberish to you, don't worry. There are plenty of useful sites out there that can put this process into laymen's terms. Here a few sources we personally recommend to get you on the right track:
-Build Your First Solar Power System (Video)
-Creating a Solar Powered Refrigerator (Walkthrough Article)
Our rating:
3.7 / 5 Stars
Pros
Cons
3) Sundanzer Solar-Powered Refrigerator - 1.8 Cubic Ft
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Specs
Features
Pros
Cons
Conclusion:
This is the simpler, cheaper alternative to the Smad Fridge/Freezer outlined above. The Sundanzer Solar-Powered Fridge is the perfect base-line solar fridge. If I could describe this fridge in just 4 words, it would be this:
Gets. The. Job. Done.
There's nothing fancy about this model other than its incredible ability to save energy. The only variable that separates this unit from any other average chest-fridge is that it runs on DC voltage, which makes it highly convenient for solar powered systems.
Other than that, it's pretty basic. The good news is, this unit runs for about half the price as its sophisticated counterpart above. So if simple, reliable, and fair priced is your prerogative, I would highly suggest the Sundanzer Solar powered chest fridge.
EdgeStar CRF321SS 3.1 Cu. Ft. Dorm Sized Fridge/Freezer (AC Powered)
Only Works with AC Outlets!
#ad
Specs
Features
Reoccurring Positive
Customer Responses
Reoccurring Negative
Customer Responses
Conclusion:
So here's the deal, the industry hasn't perfected high efficiency AC refrigerators yet.
This is Bad, because we want options.
This is Good, because it narrows the list down to a reasonable level.
We'll start with the best AC mini fridge (by FAR the best mini fridge out there). The Edgestar, high efficiency, AC powered mini fridge is the best of its kind.
It's small, efficient, and perfect for various home situations:
1) Those who need a low energy-consuming, RV refrigerator that doesn't take up too much space.
2) Those who want a secondary home refrigerator to accommodate extra food.
3) The rare, but relevant, college student who is surprisingly concerned with his electricity bill (I know, a small niche, but an important one nonetheless).
While this refrigerator may be small, there is one notable feature that makes it superior to the competition.
- Unprecedented efficiency!
Reading the yellow label above, you'll see this unit averages 270 kWh per year. That's less than 1 kWh per day! For a kWh explanation, click here.
Some minor downsides to this fridge:
- Shelves not adjustable
- Not outdoor approved
Insignia - 10.5 Cu. Ft. Top-Freezer Refrigerator - Stainless steel
Only Works with AC Outlets!
#ad
Specs
Features
Reoccurring Positive
Customer Responses
Reoccurring Negative
Customer Responses
Conclusion:
I love reading good reviews. Do you know how difficult it is to get 5 star reviews consistently? Do you know how difficult it is to get 5 star reviews consistently with a 120 pound refrigerator with a complex A/C system using multiple moving parts? Do you understand the tendency for people to have exceedingly high expectations?
I hope you do, and I hope you can appreciate a well-reviewed product like I can.
Let's establish who this fridge is designed for.
The most common customer response was how "perfect" this unit was for their apartment, basement, AirBNB, garage, attic, game-room, studio, man-cave. People love how this unit performed as their secondary refrigerator.
It's quiet, cheap, medium sized, energy efficient, and solar-compatible (as long as you have an AC solar setup). With close to 1 amp draw, this refrigerator is extremely efficient for its size. You can usually run it with 1 average sized solar panel, assuming you have some good sun throughout the year.
So who is this fridge for?
This Insignia model is for those who are looking for a fridge size somewhere between mini-fridge and contemporary kitchen fridge.
If this fridge accommodates the vacant spot you've chosen in the house, has the storage space you desire, and uses an energy level in your quota, I have no reason to believe this solar refrigerator would be anything short of perfect for you.
If you do decide to go with this fridge, I would greatly appreciate some feedback. Leave a comment at the bottom of the page. I'm sure it would be helpful to others looking.
Unique 6.0 cu. ft. 170 l Solar DC Top Freezer Refrigerator
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Specs
Features
Reoccurring Positive
Customer Responses
Reoccurring Negative
Customer Responses
Conclusion:
DC refrigerators are rare, but they're out there.
DC refrigerators are convenient in that they don't require any alterations to your normal solar-power setup. If you've got the solar panel, charge controller and DC battery, you're all set. The DC fridge will hook right up to your 12V DC battery and be cooling in no time.
All that being said, it's important to gauge how much space you'll need in your fridge. While the size of a bigger refrigerator is convenient, it can also suck the energy out of your new power-hub. So if you can settle for a smaller size, all the more power for the rest of your appliances.
There are NOT a lot of manufactures to choose from, and that's why it's imperative to do your research. The Unique 6 Sq Ft DC mid-sized refrigerator is simply the best place to start. 6 Sq. Ft runs somewhere between a mini fridge and your typical house fridge size, and so gives you a good amount of space without compromising your newly found energy.
Here are some instances where this fridge comes in handy:
1) Replacement fridge for your RV
2) Secondary fridge for extra storage
3) Primary fridge for a small family
4) Man-cave fridge for beverages
To give you an idea how other people are hooking up this refrigerator, here's a few responses I've read from verified solar users who purchased this unit:
"I hook it up to 1 solar panel 250 w and 2 batteries 100w each."
"Running two 100 watt panels and two 12 volt batteries in a houseboat."
Happy Hunting 🙂
Unique 10.3 cu. ft. 290 L Solar DC Top Freezer Refrigerator
#ad
Specs
Features
Reoccurring Positive
Customer Responses
Reoccurring Negative
Customer Responses
Conclusion:
Bottom line, if you're looking for a household size DC refrigerator, Unique has again outdone itself.
While the customer review count is low, the responses are noteworthy. All customer reviews are either 5 star happy customers, or 4 star customers stating the notorious, "...too early to tell." While I'm hesitant in forming assumptions about the "solar-buying type," I'm confident the majority of this bunch are picky individuals.
And the fact that all current reviews are 4-5 stars on Homedepot.com (as of 01/20/2020) speaks volumes.
I may not have the confidence to tell you this refrigerator is for you, but I would suggest it as a first point of interest.
This Unique 10.3 Cu Ft Dc Refrigerator is for those who need:
1) A primary house fridge (as long as a 12V DC battery is within range).
2) A secondary refrigerator for those with larger storage needs.
2 Methods to Going Solar
This section is imperative for any solar beginners.
Not all solar setups are created equal, therefore it is imperative that you buy the right fridge for the right solar equipment.
If you do not already own a solar setup, continue reading to gain insight on getting the right configuration for your particular needs.
If you already have a solid understanding of solar power and how it works, this section can be skipped.
Type 1) Battery Powered (DC) Solar Refrigerators
DC stands for direct current. This is the type of voltage that your solar panel is naturally producing (some solar panels have built-in inverters that turn DC into AC. If that is the case, proceed to type 2).
This IS NOT the type of voltage your house wall outlet uses. If you require a solar fridge that plugs into your home outlet, continue onto type 2.
Pros and Cons to a DC Refrigerator Set-up:
Pros
Cons
-3 Critical Components for a DC Solar Refrigerator
- 1A Solar Panel - (recommended 135 Watt Photovoltaic Panel) The amount of panels you will need depends on a lot of variables. The best place to start is by estimating your energy needs by using an energy calculator. We have a larger section devoted to this here.
- 2Battery (or Batteries) - The battery will act as your power storage for the fridge. This ensures that your fridge will still run after the sun goes down. It is recommended you get a 100 amp hr 12V deep cycle battery for proper power and longevity.
- 3Charge Controller - Charge controllers do exactly what their name implies, they make sure the battery quits charging after it's fully charged. This is important for battery health and safety. While overcharging a battery may seem trivial, overcharging batteries is very dangerous and can cause excessive gas exposure or explosions. A charge controller is A MUST!
This is what the basic circuit looks like:
When in doubt, always seek out a professional. But if you'd rather do it yourself, there are countless youtube videos that can guide you along.
This video shows you step by step how to hook up your solar panel to the charge controller, and your charge controller to the battery.
From there, all you have to do is connect your solar fridge to your battery. Positive clamp to positive terminal on battery, negative clamp to negative terminal on battery.
Again, if you lack the proper tools or don't feel up to the task, there is no shame in calling an expert. Saving a buck is nice, but the comfort of knowing your solar is hooked up safely is priceless.
-DC Solar Product Recommendations
You should have no problem finding quality equipment on your own, but here's a few products other solar fridge owners recommended:
#1 Battery
WindyNation 100 amp-Hour 12V Battery
(Affiliate Link)
Charge Controller (Option #1)
EPEVER 60amp Charge Controller
(Affiliate Link)
Charge Controller (Option #2)
Renogy Wanderer Li 30A 12V
(Affiliate Link)
Recommended Solar Panel
BougeRV 170 Watts Solar Panel
(Affiliate Link)
Type 2) High Efficiency (AC) Solar Refrigerators
AC stands for alternating current. This is the current that runs through your house and provides electricity to your 110V outlets (220 V in EuropeP).
Converting DC to AC requires just one more piece of equipment...
an inverter.
Here are some things to consider if you're transitioning your house outlets to solar power.
Pros
Cons
- 4 Critical Components for an AC Solar Refrigerator
- 1Solar Panel - Recommendations above
- 2Battery (or Batteries) - Recommendations above
- 3Charge Controller - Recommendations above
- 4Inverter - An inverter takes DC (direct current) created by your solar panels and converts it into AC (alternating current), which powers your household outlets.
The order of the circuit should go like this:
This video shows you step by step how to set up your solar panels for an Alternating Current (AC) system. The video also provides some extra tips to ensure a safe installation.
-AC Solar Product Recommendations
Again, you should have no problem finding quality equipment online. But if you're looking for a good place to start, here are products other customers were very happy with (my recommendations for the solar panels, batteries and charge controllers are the same as above).
Inverter
1200W Power Inverter DC12 Volt to AC 120 Volt with 20A Solar Charge Controller and Remote Control (Affiliate Link)
How Many Solar Panels Do I Need?
Looking at the facts, going solar seems logical.
But what about the initial investment? How big will my panels need to be, and how many watts? How many batteries will I need?
Any solar expert will tell you a good system starts with a ballpark estimate. Too many variables are involved to get things spot-on every time. This deters a lot of people from making the leap. Don't be discouraged. It's all about coming up with a rough estimate, and then overcompensating.
Step #1: Figure out how much energy you need.
Here's an energy calculator to help you evaluate how much energy you'll need to power your electronics.
Step #2: Figure out the space you have available for solar panels (outside) and batteries (inside).
Take a look at your property/RV and see how much square footage you have available for solar equipment. This includes both outdoor space for solar panels, and indoor space for batteries (expect the batteries to be a similar size to a car battery).
Do you have the space provided? If not, could you create the space?
Step #3: Match the solar equipment with your space and energy criteria. Then overcompensate by accounting for cloudy days and dark nights.
Solar panels - Keep in mind that the wattage rating for a solar panel is the highest potential wattage during ideal temperatures and peak sun hours. Your solar panel will not be drawing this amount of energy all day.
Go Green Solar is a solar company with spectacular reviews. We always recommend getting in touch with an expert to get their recommendations.
Battery Power? - Wholesale solar has an awesome solar battery bank calculator that can help you decide which batteries will perform best with your layout.
Choosing the Best Solar Fridge For You
We're all guilty of making impulsive purchases in life, some of them more inconsequential than others. But let me be the voice of reason before you make this regrettable mistake with your solar system.
Take a moment (or two) and consider these variables to ensure you'll be content with your system years down the line.
Size
Size is no doubt an important factor when shopping for a solar powered fridge. Go too big, and you're using precious energy to cool unused space. Go too small, and you'll find yourself overstuffing your fridge, decreasing its cooling power.
The key is to find the healthy medium.
Evaluate your typical fridge loading space for the amount of food you use now. Then take that space and go a tad bigger. This will ensure you have enough fridge space for your everyday food supply as well as a little extra space for those special occasions.
Efficiency
Yes, one of most important variable for choosing the right fridge is efficiency. You'll find the DC powered refrigerator/freezers tend to be the most efficient (besides battery-free solar fridges), but they are also the most expensive.
The efficiency of your model can usually be found on a big yellow sticker that comes with the fridge. It should look something like this:
As you can see from the image above, this fridge uses 270 kWh (kilowatt hours) per year. A kilowatt hour is a measurement of energy consumption, not to be mistaken for a kilowatt per hour.
Don't worry too much about the terminology. Just know this is a unit of energy consumption.
Rule #1: Find a fridge with a kWh per year of under 360.
That's approximately 1 kWh per day and merits a very efficient refrigerator.
***Be careful about models that boast 250 kWh per year. Such a low energy consumption could mean low cooling capacity. Make sure and check the reviews to see what other customers have to say.
What is Energy Star Certification?
Energy Star Certification only refers to AC (alternating current) powered refrigerator/freezers. Energy star is a certification developed by the Department of Energy (DOE) to motivate manufacturers to make more energy efficient products. The energy star stamp indicates the fridge/freezer has met the strict guidelines set down by the DOE.
Proper Insulation
The concept behind refrigerator insulation is simple; keep the heat out, and keep the cold in. The thicker the insulation, the better your fridge maintains temperature.
This results in the compressor kicking on less frequently, and thus less energy usage.
There isn't a one-diameter-fits-all thickness to insulation. 10 cm (100mm) thickness seems to get a good response from customers. If the website/store doesn't supply this information, make sure to find the product manual to find insulation thickness. This is a critical component of energy efficiency.
Transportation
There's nothing worse than following your exciting new purchase with a cumbersome installation. If you plan on transporting the fridge frequently, make sure to invest in a unit that has wheels or casters. This can be a savior for someone who is doing the installation themselves.
AC or DC Refrigerator/Freezer?
Deciding whether to go with an AC (alternating current) or DC (direct current) refrigerator comes down to your solar setup. The simplest of setups entails a solar panel hooked up to a series of DC batteries.
So for the sake of simplicity and efficiency, a DC powered refrigerator would be most effective.
A more advanced setup may have an inverter in place, which transforms the initial DC current into AC current. This will require an extra piece of equipment (the inverter) and is generally less efficient.
However, it is far more convenient for those who want to hook up the solar system to their house 110/220V outlets
Temperature Control
Temperature control gives you everything the name implies:
more control.
The ability to manipulate your fridge temperature doesn't just give you more control over your food temperature, it gives you a say in your energy consumption.
If you don't require freezing temperatures, set your gauge to a warmer setting. If This way you can assure you're using only the solar energy you absolutely need for the food you have.
What is a Solar Fridge?
The title "solar refrigerator" can be a little deceiving. At face value, it seems like this implies the fridge comes with a solar panel that runs the fridge on its own. While these units do exist, solar powered refrigerator/freezers are actually just efficient enough fridges that can handle the lower energy input of solar set-ups.
How Do Solar Refrigerators Work?
No system is the same, but the premise is essentially universal. Solar panel hooks up to battery. Battery hooks up to refrigerator. Refrigerator runs off solar DC power (usually). Battery or solar panel can also hook up to an inverter, which transmits the DC (digital current) into AC (alternating current). It all depends on how you want to do it. No system is "better." It just depends on if you plan on using your solar system for other appliances other than your fridge.
How to Use a Solar Refrigerator
While it may be obvious, using your solar refrigerator properly ensures the most efficient and effective system.
Proper Sun Alignment
Aligning your solar panel for optimal sunlight allows you to get the most energy for the longest duration of time. The University of Calgary states that the Northern Hemisphere inhabitants should point their solar panels true south, and southern hemisphere inhabitants true North (1).
Set Temperature Correctly
It always amazes me to see how many people don't know their refrigerators have temperature controls. A lot of people just plug it in and assume it works right.
But this couldn't be farther from the truth.
Solar Refrigerator Precautions
It is alway highly recommended to get an electrician to help figure out the energy requirements of your solar system plan. It would be a shame to buy all the equipment, just to find out you've gotten the wrong battery or charge controller for your particualr energy needs.
Even if you don't know an electrician, get in touch with someone who knows solar powered systems well and has adequate experience with this kind of equipment.
Frequently Asked Questions
Here are some of the most common questions I discovered reviewing the products:
How do I Build a Solar Fridge?
I am not an electrician, and therefore do not feel equipped to giving you a solar fridge building tutorial. But there are some videos and articles worth looking into. Here's a couple that I found useful:
How to Build a Solar-Powered, Off the Grid Refrigerator (How-to article)
Homemade Off-Grid Refrigerator (Video)
Can Solar Power Run a Refrigerator?
It wasn't until recently that refrigerators became efficient enough for solar to become practical. Most of our household (nonEnergy Star) refrigerators would need 3 or more regular sized solar panels to run effectively. To run three or more solar panels for a single appliance seems highly counterproductive since one of the prevailing ideas is to save money.
Nowadays, there are efficient AC and DC refrigerators that can easily run off of one solar panel.
What is the Best Fridge for Solar Power?
While it may be frustrating, there isn't one superior fridge. There is, however, a superior fridge for your particular needs. The model summaries above outline which fridge is best for which situation. While I may not be able to hit every angle, please leave a comment below if you have any questions. If I've failed to meet your fridge conditions, I may be able to steer you in the right direction.
How Much Solar Do I Need to Run a Fridge?
The amount of solar energy to sustain a refrigerator's demands is obviously variable. But with most DC powered 12/24V systems, one 135 Watt photoVoltaic Panel (PV Panel) should suffice. Again, the best option is to find someone with a system similar to the one you want. Compare your systems and see how many panels would work best for your needs.
Concluding
Continually making the transition to solar can be a fun (or challenging) adventure. Watching those monthly energy bills continue to drop has to be one of the most rewarding feelings ever.
Taking your refrigerator off the grid is definitely one of the major solar milestones, and something to be proud of. My hope is that you find the solar refrigerator that meets your expectations and provides quality for years to come.
I hope this was helpful. If you have any comments, please leave them below, and I'll try to get back to you within 24 hours.
Cheers,
Michael
Founder of Robust Kitchen
References
Battery-Free solar fridges
You missed one out. EcoSolarCool has solar refrigerators. A range of sizes too including portables. Been in business since 2007
Hey Jenny,
This post is in DIRE need of an update. It’s been on my to-do list for far too long. Will be getting to it within the first week of May.
Will definitely be looking into your recommendation!
Cheers!
Michael
The average refrigerator takes about 3 or 4 average solar panels to run. Power consumption depends on how much food you keep in it, how old or new your fridge is and how long you leave it open.
Thanks Amertec, I added some information to emphasize the many variables involved with estimating solar panel investment.
Cheers!
Michael
Thanks for the information, I want to ask just one question. Can I take ACOPOWER R40A on a 3 day trip in a hot weather?
Hey Mike,
So the R40A has approximately 10-15 hours of freezing time on one battery charge. This will vary on how hot the cooler is and how much your storing in the cooler. For a 3 day trip in hot weather, the solar panel chargers might get you through as long as your consistent with putting them out (and you have the solar panels). If you plan on driving much of the time, you can also charge using the car port (even though this may be a relatively slower charging strategy). I highly recommend investing in a secondary battery to make up for the uncertainty.
I know, nothing concrete. It’s a hypothetical whose results depend on a lot of variables.
I emailed AcoPower to see what they think. I’ll get back to you with their response ASAP.
Cheers,
Michael
Thanks for your response. I'll purchase it and let's see how it works.
Awesome, I’ll get back to you when I receive an email from AcoPower. We’ll see if they have any recommendations for your particular needs.
Enjoy the day Mike
I'll be reading your upcoming articles to buy the perfect product. Thanks brother!
Low cost appliance repair is a leading refrigerator repair place in Buffalo Grove, Long Grove, Antioch, Arlington Heights, Barrington etc.
Enjoyed every bit of your article. Really looking forward to read more. Much obliged!.
I loved your blog and thanks for publishing this!! I am really happy to come across this exceptionally well written content regarding best solar fridges . Thanks for sharing and look for more in future!!
Thank you for the kind words 🙂
Hi there, I believe your site could be having web browser compatibility problems.
When I look at your web site in Safari, it looks fine however, if opening in Internet Explorer, it’s
got some overlapping issues. I merely wanted to give you a quick heads up!
Apart from that, excellent website!
Huge thanks! I’ve never looked through internet explorer. I will be contacting my theme to fix the issue. Thanks again!!
ACOPOWER R40A kept my veggies drinks and insulin cool throughout Burning Man! And I was in a tent!! Only negative is the display panel can pop out
ACOPOWER is an awesome company. We watched some of the videos documenting their first release at a convention, and their owner just seems like the coolest guy (at least, we think it’s the owner). We will be placing your display panel complaint on the “cons” list. Thanks for the response Andrew 🙂
Cheers!
Michael
Thank you for your reply. I have read many of your articles. They are very useful to me. I’ll keep reading your new post!
With your varying budgets in mind, we’ve selected Deep freezers with generally suitable and affordable prices for both high and lower budgets with the best quality available in the range.
Comparable to pure AC types, how powerful and efficient are solar freezers? I mean in terms of chilling and freezing.
Hey Malachi,
Thanks for the great question. I’m so used to getting spam on my comments, it’s a relief to finally get a question related to the content. Your question is a very good one, whose answer may not be true across the board. If you’re truly interested and looking for specific details, I recommend getting in touch with a solar electrician. A solar company may be able to give you specific ratios and stats (go green solar has an online chat)
https://www.gogreensolar.com/
Creating a “solar fridge” is as straightforward as creating a low wattage, high-efficiency refrigerator/freezer. Some of the companies who previously made high-efficiency fridges just stamped solar on their title because they knew their units could handle the typical, lower energy output of solar.
Solar fridges attempt to draw as little power as possible while providing enough energy to sufficiently cool the area. So yes, a usual outcome of this is slower cooling and smaller area refrigerators (not all the time). To answer each of your questions directly, most of the solar fridges will have lower than usual power, with higher than usual efficiency.
Hope this helps, let me know if there’s anything else I can do for you
Michael