# Emergency solar generator for freezer



## pugsan (Oct 29, 2016)

Any advice on the possibility of creating a solar generator to run a 5 cubic ft freezer in emergencies? Say, the power goes out for a few days. Does anyone know if it's possible to reasonably build or buy a system that would run such freezer?


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## hiwall (Jun 15, 2012)

pugsan said:


> Any advice on the possibility of creating a solar generator to run a 5 cubic ft freezer in emergencies? Say, the power goes out for a few days. Does anyone know if it's possible to reasonably build or buy a system that would run such freezer?


Yes you certainly can and if you are a very smart shopper maybe for as little as $500


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## forluvofsmoke (Jan 27, 2012)

The low-down: since you're talking about emergency use only and not long-term, you can run a smaller battery than a normal system would require. The reason you can do this is by shutting the freezer down in the afternoon when solar harvest is low you won't deep-discharge (actually, it would kill it) the small battery, then, start it back up in the morning when solar starts putting out juice again. Chest freezers hold their cold well, so running for 6-7 hours during daylight only is enough to keep food frozen overnight, and then some...set the freezer to it's coldest setting so it runs the whole time you have solar for added cold thermal storage (mass of food).

The battery could be a small as a ~50Ahr, as long as it can provide the output for the surge amps to start the freezer compressor (inductive motor) while the solar panels provide a bit more than running watts for the compressor and charge the battery at the same time. Being your system will basically be a stand-by unit, I'd recommend a 80-100Ahr Marine battery...they're not expensive and can provide a good punch of output amps when called upon, and won't feel abused if you're not discharging them regularly. Marine batteries are basically a trade-off, and are a hybrid mix of cranking and deep cycle battery. They don't have a high cycle-life as a result, unlike a true deep cycle battery which can last from several hundred to several thousand cycles, depending on the battery design and manufactured purpose, and of course, depth of discharge, care and maintenance.

Your inverter will need to kick out about 8-10 times the running watts of the freezer for start-up. If your freezer runs @ 125 watts you'll need an inverter capable of around 1000-1250 watts surge. A 200 watt solar panel and 20 amp PWM controller should handle it fine with proper installation (good azimuth, elevation, no shade)...manually pointing the panel directly at the sun, and adjusting several times throughout the day will maximize solar harvest. BTW, not knowing the model, age and efficiency of your 5cf freezer it may run at anywhere from ~100-160 watts...don't forget the surge for start-up.


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## Caribou (Aug 18, 2012)

A larger chest type freezer might actually draw less to very little more, check the power consumption on a few units.

When the freezer is not running it can be kept cold longer by covering it with some blankets. Make sure you uncover when you start it up as many units dissipate heat through the outside casings of the unit.

If the freezer is not full you can extend the cold period by filling it with bottles mostly full of ice. Along the same idea a full large freezer should last longer than a full small freezer due to the increased mass. Place a snowman on the parking lot and place a snowball next to it, the snowball will thaw much faster due to a smaller mass.


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## hiwall (Jun 15, 2012)

> If the freezer is not full you can extend the cold period by filling it with bottles mostly full of ice.


Or most anything of high mass. Large chunks of steel or lead would be optimal for cold retention though the suggested water jugs are the most common and also provide added drinking water when they thaw.


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## Caribou (Aug 18, 2012)

hiwall said:


> Or most anything of high mass. Large chunks of steel or lead would be optimal for cold retention though the suggested water jugs are the most common and also provide added drinking water when they thaw.


LMAO, just trying to figure out how to explain to the Mrs. why there is a bunch of birdshot and bullets in the freezer.:eyebulge:


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## hiwall (Jun 15, 2012)

In forluvofsmoke's post above while accurate the OP would be depending on the sun shining bright everyday to work. We don't know where he lives and the emergency could be weather related and not have sun for the duration of the emergency.
Safest and least expensive would be a generator that he would run only as needed.


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## pugsan (Oct 29, 2016)

I should've mentioned this earlier. The freezer is a top loading Black and Decker 5 cu/ft freezer requiring (at one point or another) 12.8 amps and 115 volts to operate. I get 8-10 hours of direct sunlight and 12+ hours of daylight daily here near Austin, Texas. I've found some information over the last year on the specifications of components required for the emergency system I'm pondering, but more is always welcome. Funds are not a problem, so if you have any advice on high quality components and/or links to any diagrams on constructing such a system then that would be extremely helpful. This is simply a hobby project I'm working on. Thanks again everyone.

Would I like to create a system that could run the freezer full time if it's even feasible? Sure, but I prefer smaller goals when starting a new project with technology I'm unfamiliar with.


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## readytogo (Apr 6, 2013)

Get a Kill-A-Watt meter at home depot;http://www.homedepot.com/p/P3-International-Kill-A-Watt-EZ-Meter-P4460/202196388.will help you on all your calculations also the solar power map here will tell you about solar hours in your area;http://www.nrel.gov/gis/solar.html ,and forluvofsmoke gave you some great info, the better the equipment you buy the better system you will have period ,but never run your system below 50% and take inconsideration that all the equipment in the system consumes power; inverter, wires (voltage drop factor;http://www.southwire.com/support/voltage-drop-calculator.htm), timers, charge controller`s, etc ,so good luck.


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## hiwall (Jun 15, 2012)

12.8 amps and 115 volts to operate = 1472 watts, which is a lot. Plus the starting load which would be substantially more watts. I'm guessing that you possibly read the tag wrong? 
The small frig/freezer in my RV runs at 88 watts and draws about 1200 watts at start up. To run that in sunny Arizona I have 275 watts of solar power, a 750/1500 watt inverter, a 30 amp MPPT solar controller, and just two 12 volt deep cycle batteries. But I am only out when it is sunny. You would have to expect some cloudy/rainy days. 
Working on the 1400 running watts you would need way more solar panels than I have and way more batteries along with a much larger inverter.


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## forluvofsmoke (Jan 27, 2012)

hiwall said:


> In forluvofsmoke's post above while accurate the OP would be depending on the sun shining bright everyday to work. We don't know where he lives and the emergency could be weather related and not have sun for the duration of the emergency.
> Safest and least expensive would be a generator that he would run only as needed.


That's a very good point, and well received by me. I didn't think fossil fueled electrical generation was in the scope of this post, so didn't mention it.



pugsan said:


> I should've mentioned this earlier. The freezer is a top loading Black and Decker 5 cu/ft freezer requiring (at one point or another) 12.8 amps and 115 volts to operate. I get 8-10 hours of direct sunlight and 12+ hours of daylight daily here near Austin, Texas. I've found some information over the last year on the specifications of components required for the emergency system I'm pondering, but more is always welcome. Funds are not a problem, so if you have any advice on high quality components and/or links to any diagrams on constructing such a system then that would be extremely helpful. This is simply a hobby project I'm working on. Thanks again everyone.
> 
> Would I like to create a system that could run the freezer full time if it's even feasible? Sure, but I prefer smaller goals when starting a new project with technology I'm unfamiliar with.


EDIT: yeah, that 12.8 amps must be start-up surge...no way they could even sell a small freezer with that high of energy consumption....it would trip 20amp breakers on start-up, and most household 120VAC duplex receptacle wiring is for 15amp, except clothes washer or dishwasher circuits.

I think you're taking a good path, considering options and educating yourself on PV, battery storage, and energy consumption of your prospective RE-powered subject(s).

Renewable energy has been a fascination of mine for over a decade...hmm, thinking back now, it must be close to twenty years. It has resulted in my scouring of the web for info. Technology has changed for the better, become less costly and more competitive. Even now, though, I sometimes feel like that robot in the movie...oh drat, forgot the name of it...when I need "more input". It seems that once you understand the basics of power generation with PV, transferring it to storage from the source, and transmitting it to the end use, then everything else starts to fall into place regarding type/capacity of the components you'll want to start with to build a system. Starting small is good...you'll learn much from it, and gain confidence and skills to go bigger when/if you decide to do so.

Yeah, you can call it a hobby if you wish. That's what it is for me. I have some micro-sized PV/storage that I have around for SHTF, but also use for daily needs. Having it and using it so you can learn about it helps you go further with your goals.


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## Viking (Mar 16, 2009)

pugsan said:


> I should've mentioned this earlier. The freezer is a top loading Black and Decker 5 cu/ft freezer requiring (at one point or another) 12.8 amps and 115 volts to operate. I get 8-10 hours of direct sunlight and 12+ hours of daylight daily here near Austin, Texas. I've found some information over the last year on the specifications of components required for the emergency system I'm pondering, but more is always welcome. Funds are not a problem, so if you have any advice on high quality components and/or links to any diagrams on constructing such a system then that would be extremely helpful. This is simply a hobby project I'm working on. Thanks again everyone.
> 
> Would I like to create a system that could run the freezer full time if it's even feasible? Sure, but I prefer smaller goals when starting a new project with technology I'm unfamiliar with.


That seems too high of amperage for a 5 cu. ft. unit, our 16 cu.ft. chest freezer is rated at 5 amps. As mentioned, the condensing coils are attached to the freezer side sheet metal, if you use a blanket or other extra insulation, put it on the lid only.


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## Viking (Mar 16, 2009)

I designed our solar backup system to mainly take care of two fridges and one chest freezer, but also to have some lighting on a small scale. It may seem like overkill to the OP but sometimes our power can be out for over a week, we are down the list for importance for power restoration. Anyway, we have 20 (Costco, affordable) 6 volt 205 amp. hour golf cart batteries, series for 24 VDC, parallel for 1025 amp. hours and not yet installed, eight 195 watt monocrystalline solar panels for a total of 1560 watts. I have a single, stackable, Magnum Energy pure sinewave 4000 watt inverter/charger, which, at this point I have found to be more than adequate for taking care of said refrigerators and freezer. When we have had power outages the transfer is so quick and smooth the first time we lost power, that I wasn't sure the backup system was running except for one light we usually keep on, that runs only on grid power, was off. The charge system of the inverter keeps the batteries in top codition, but I will be a lot happier when the batteries are taken care of by the solar array and the MPPT controller.


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## WSSps (Sep 30, 2016)

https://www.amazon.com/gp/product/B...2&tag=newlifonahom-20&linkId=FL3QQKAIKOQXZUO5

This can be used to convert a chest freezer to a chest refrigerator. Apparently it uses anywhere from 1/4 to 1/3 the power of a upright. People off grid use this controller on solar often. Would be good to have two chest freezers and one of these on hand to just in case.

WSS


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## TheLazyL (Jun 5, 2012)

Solar Generator?

*Solar* energy is radiant light and heat from the Sun that is harnessed using a range of ever-evolving technologies such as solar heating, photovoltaics, solar thermal energy, solar architecture and artificial photosynthesis.

*Generator* is a device that converts mechanical energy to electrical energy for use in an external circuit. The source of mechanical energy may vary widely from a hand crank to an internal combustion engine.


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## WSSps (Sep 30, 2016)

Ya there is another one of those word compilations that makes no sense.

It derives from it's use, not a description or definition but a progressive/living phrase.

Diesel generator: generator powered by a refined fossil fuel known as diesel

Propane generator: generator powered by lp fuel commonly known as propane

Gas generator: generator powered by a fossil fuel sometimes referred to in America as "gas", also called Gasoline

Solar generator: generator powered by radiant light supplied by our star. the sun. 

Here in so. Cal, we have government agencies that now require "solar generators" on certain projects and jobs. I would say the reason it is only some and not all construction projects is because there are not enough gov. agents/inspectors to cover ALL projects.

It used to be that the AQMD left stationary (not self propelled) engines under 50hp alone and only regulated above that level, know they are requiring engines to 25hp be Updated to tier II or better, meaning generators are starting to show up on the radar. Having a "solar generator" on site makes the inspectors happy. A happy inspector usually goes and harasses someone else.

Greetings from the Repulik of Kalifornia!!


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## pugsan (Oct 29, 2016)

readytogo said:


> Get a Kill-A-Watt meter at home depot;http://www.homedepot.com/p/P3-International-Kill-A-Watt-EZ-Meter-P4460/202196388.will help you on all your calculations also the solar power map here will tell you about solar hours in your area;http://www.nrel.gov/gis/solar.html ,and forluvofsmoke gave you some great info, the better the equipment you buy the better system you will have period ,but never run your system below 50% and take inconsideration that all the equipment in the system consumes power; inverter, wires (voltage drop factor;http://www.southwire.com/support/voltage-drop-calculator.htm), timers, charge controller`s, etc ,so good luck.


Oh thank you so much. I appreciate the links.


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## mosquitomountainman (Jan 25, 2010)

hiwall said:


> In forluvofsmoke's post above while accurate the OP would be depending on the sun shining bright everyday to work. We don't know where he lives and the emergency could be weather related and not have sun for the duration of the emergency.
> Safest and least expensive would be a generator that he would run only as needed.


I agree. The only time we had power outages when we lived on grid was during storms. Those are the worst conditions for solar power. If you want something for emergencies save yourself a bundle of money and just get a generator and stock some gas/diesel/propane ... whatever.


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