Solar Power, Battery Backup and Power Inverter for an Apartment

Greetings:

I live in an apartment; I am constantly thinking about a natural or man-made disaster that may knockout the electrical power for an undetermined amount of time. I am a novice and I was wondering if the Harbor Freight type 45 watt solar panels, a 1500-watt power inverter and battery/batteries (or other affordable solar items) would be worth investing in.

My main concerning is keeping power to my refrigerator on. The refrigerator’s rating off the data plate is 100 volts at 50 Hz, 100-127 volts at 60 Hz and 6.5 amps. Using 120 volts and 6.5 amps equals 780 watts. Currently with the setting at half way, the refrigerator runs about 20-25 minutes and is off about 40-50 minutes before running again.

With no electrical power, I would turn the setting higher (as in the temperature) to conserve battery power. I’m not too concerned about lights (drawing attention), maybe some TV (.92 amps) for news.
If I did my calculations right the refrigerator would run a total of over 7 to7.5 hours a day.

I receive the sun’s rays most of the day and less during the winter months.

My questions are:

-Will a deep cycle battery holdout? Or, will it be drained within a day?
-Are there any middle of the road alternatives?
-Is it worth investing in a makeshift solar system?
-Are the Harbor Freight items worth investing in? Or, Fry’s Electronic items (Wagan, Rhino or Sunforce)?
-If the above products aren’t reliable, what products are reliable?


Thanks,
KingPurplePimp

 

You can largely forget solar/battery/inverter for running a refrigerator. It can be done but it is expensive especially considering the short run time you'd get. There are off the shelf battery packs with a inverter and battery charger all in one package you could consider. They are expensive for the amount of power they supply and you still have the life span of the batteries to consider.

Back to the solar panel, batteries and inverter idea. The current you mentioned for your fridge is the running load. It may take twice that to start the compressor so you have to plan for that initial surge load. It's good that you converted to watts but you should go a step further to see that while the fridge only pulls 6.5 amps at 120 volts it would pull 65 amps at 12 volts and that not including the inefficiency of an inverter. It would take a large battery bank with big cables to supply 65+ amps for any period of time.

When the power goes off don't open the refrigerator door. Changing the thermostat setting will not help and the cold lost by opening the door will do more harm than good.

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Here is a solar/battery/inverter system that might work for your fridge. It's $2'000 and only has 220ah of battery capacity which would be diminished if using it high drain.

 

Solar would be great for charging your phone or running some LED lights or a small fan, but would cost a fortune to power a refrigerator, and the amount of batteries you would need would be impractical. If your apartment has a balcony or patio for an ultimately cheaper price, you could buy a small (~1kw) quiet generator which is also very portable so you can take it camping or with you when you move. Honda is the "best" and most expensive in this category, but there are other less expensive brands as well. Or just accept a hundred bucks in spoiled food every other year and be further ahead than either option.

 

IF you could get full output from the solar panels for a minimum of ten hours a day they would supply at best one-half of the power needed for your refrigerator. Trouble is, there is no way that you can get full output from those panels for that length of time.

Small solar is rarely practical and especially not without some sort of government subsidy. You will never get a subsidy for your proposed installation and you will never get much more than 50% of the panel's rated output in your situation.

I wanted to do a small solar to serve just my Internet connection; modem, router and VoIP telephone. Doing the math I came up with a minimum of $600 worth of equipment, not counting wire or mountings for the panels, and even then it would be iffy. At my cost of power, ten cents per kilowatt hour, it would take over ten years to just break even.

 

Well you could by a kerosene refrigerator to use during power outages but you'd be looking at low 4 digit prices.

 

Unless you live in some third-world country, you're stressing too much about losing power. I've lived all over the U.S. in my 60+ years, and have never, not even once, lost power for more than maybe 24 hours or so. If you keep the refrigerator door closed, the food will be fine for a lot longer than that. If you're hit by a tornado or something else serious, losing power would be the least of your concerns.

 

I've gone through four power outages of five days or longer in my adult life so I can understand. Worst is when it comes during summer. You can always put on a sweater in winter but when it's 90+, humid and the sun beats down on the house all day I can appreciate the importance of a cold beverage or better yet... air conditioning. I will say being in an apartment would be the worst.

If truly worried about a power outage I would buy a 2'000 watt inverter style generator. It will be about $600-$1'000 but would provide the power needed to run a fridge and you could even plug in a window AC unit and run some lights and the TV. Make sure it runs then properly prepare it for long term storage with no fuel in the generator so it's ready when you do need it. The big problem is fuel. Often when the power goes out over a large area there is no power to operate the fuel pumps at gas stations and gasoline does not store well. But... you car's fuel tank is probably the best resource if you are prepared with a hose to siphon the gas.

 

I think we can dismiss the idea of using a generator in an apartment complex. First, where would a person store a generator and fuel? Second, you would have to have a trained lion leashed to the gennie to keep it from being stolen when in use. Third, running an extension cord from the gennie would only make sense if you had a ground floor apartment.

Most apartment complexes are in or very near to cities and the power companies ALWAYS work outages in a manner that gets the most customers back on line the soonest. This is why those that live in the sticks are out the longest. My parent's lived in Seattle, about half-way between the city center and the northern boundary, and in some forty years they lost power exactly three times and two of those times were from a car hitting a utility pole and the power was restored in an hour or less. The third time was a huge storm that caused massive failures throughout the region and even then their power was back on in less than four hours.

Bottom line, for apartment dwellers it is unlikely that you will be out of power for more than a day and for that period of time it is not a severe hardship for most people. If you ARE out longer then more likely as not you will have even bigger problems than simply being without power and will likely need to move to a temporary shelter run by the government.

 

Thanks to all for your input and ideas.

I would love to have a generator; it would stay outside on the porch. However, some of my fears are jealous neighbors complaining of the exhaust, the noise and not being able to use my power. Plus, where would I ground it? I live on the second floor and only two spots come to mind in a pinch: (1) the rain gutter or (2) connecting it to the the outdoor receptacle on the porch.

Plus, they don't want residents to have grills on their patios due to the fire codes. So, I'm sure a generator would be a no go with the apartment complex.

I may still consider some sort of solar emergency backup for a TV and computer usage.



KingPurplePimp

 

Do you mean connect the generator to the earth? Why would you want to do that?

 

Yes. Aren't all generators suppose to be grounded?

 

Honestly, I've never hooked up any of my generators to a ground. If installing a permanent backup generator like you see on a concrete pad outside a building yea, I would ground it but the nice thing about portable generators is they are... portable (no dedicated wiring or infrastructure required).

As for the noise that's why I recommended a inverter style generator. They are generally the quietest generators available. I'm a big fan of Honda's and think the EU2000i would be perfect for an apartment balcony. Honda's are very good & reliable but expensive. The 2'000 when running a light to medium load could be described more as a loud purr. Not offensive at all even when standing right next to it and they are very fuel efficient and don't produce noticeable fumes. It's a gas engine so there is exhaust but it's a really clean running machine. There are other brands and many of them are also very good but in general inverter style generators tend to be premium so you tend to not find cheap, smelly, noisy models.

 

Well, kind of, sort of, maybe, yes. But you have to understand the WHY of grounding/earthing.

There are essentially two reasons to "ground" a generator, the first is for lightening protection and the second (far more important in my opinion) is to provide the required low impedance (low resistance) path to allow for tripping of circuit breakers under fault conditions. It is this second reason that is behind the use of the green wire and round prong in all grounded tools and appliances in a home.

Using a portable generator you would be using three-wire extension cords plugged into the generator's receptacles and run to the refrigerator, electric coffee maker, fry pan, microwave oven, etc. All these appliances would be "grounded" (provided they have a three-wire cord) back to the generator and THAT is the grounding that counts. Any fault would then trip the circuit breaker on the generator. An actual connection to the earth would do nothing.

Since it is an apartment you would not be able to have any fixed wiring powered from the generator but would have to use extension cords from the generator to power anything. This is as safe as it can get.

 

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Concerning the grounding comment I made; I was originally visualizing the generators that require hard wiring directly to the load studs. I didn't think about the plug into the receptacles only type generators. The EU2000i is a nice unit to have in an emergency though. However, where I am at it is very quiet at night. And, for what little noise the EU2000i or similar units make it'll will attract attention.

 

Leaves you back at the beginning. Minimize opening the refrigerator during power outages. Move to a place that has a standby generator (probably few and far between). Move to a house where you can have a generator (probably not an option), or suffer like all your neighbors for the few times when there is a power outage. Some homeowner insurance policies will pay out for frozen food lost during a power outage, less a deductible, I'm not sure about renter's policies.

 

Of course there is always the best option when the power's dark, which is to empty the freezer, put it all on the BBQ and have a big picnic with the neighbors while you wait for power to come back on. You might be out some food, but at least you'll have friends.

 

Do remember I live in Wales not US but I would consider a generator better than solar panels for emergency power.

First the freezer cheap older freezers have single phase motors with a massive start up load, and also have a device to re-start the motor should it try to start when there is still pressure in the system these will fail if used too often, in the main they only operate when you unplug and re-plug in while under load but long extension leads or generators/inverters which are not big enough.

However the more modern units are three phase motors run with built in inverters and have very little extra start load and would not really have a problem with slight under voltage. Also likely would not worry if true or simulated sin wave supply.

Now onto generators the less noise the more you pay. External combustion engines are very good but the price is something else. The Wispergen with the Sterling engine it seems is very good and in the UK a version is being marketed that is combined with the gas central heating and uses the heat from the exhaust to feed power back into the national grid but the cost is really not worth if for a freezer supply cheaper just to re-stock after each power cut.

Inverter generators make less noise than the standard type as the revs depends on load not the frequency of the supply. Not as expensive as the WisperGen but normally only petrol. WisperGen will run on anything that burns. So with petrol it does not keep as well as Paraffin (28 sec Gas Oil) or Diesel (35 sec Gas Oil).

There are fridges designed to run direct off DC power, but the Peltier system is inefficient in the UK the 230 volt version is banned only the 12 volt system is allowed by our efficiency laws if you want to run on 230 volt (remember I live in UK) then you have to buy a power pack.

Our caravans use inversion fridges because duel fuel they are not covered by the efficiency laws they are better than the Peltier system but not as good as motor driven units. Often will work on 12 volt, 230 volt or bottled gas one in my caravan could see off a bottle of gas in three weeks nothing else running I would say bottle was about 4 gallons in size. No noise is important for a caravan.

The problem is you would be putting heat into your home running the inversion type, even in the UK it got caravan too hot and I had a 12 volt fan to remove heat outside. But likely this is the best method of getting around frequent power cuts.

My freezer has a time it is claimed to survive a power cut, but when the motor failed it did not last anywhere near that time. I think likely the de-frost heater cut in which would reduce the time but this is also something to think about with inverter fridges and freezers, although they may start and run at less than 60W the de-frost (Or frost free) heater can take 150W so you need to allow for that. But with no power larger units should last 8 hours.

I did consider a generator but it is better in UK just to insure against fridge/freezer failure the premiums for insurance are at a level just simply not worth doing anything about power cuts.

 

For Kingpurplepimp....

Forget solar and batteries. It would cost you more than eating out for a month or two or even a year depending on how big of a system and the quality of the components.

If you do a search on YouTube there are plenty of preppers who have small to very large solar systems. But the cost is very expensive, and would be very difficult to do in an apartment. You can't do much with a 50 watt harbor frieght panel, except play bit and learn. Running a fridge takes serious power, at least 850 to 900 watts per day. Plus, the power inverter has to be able to handle the power surge at start up. I'm planning a system for a small home, and the only real power draw is a fridge, and I'm looking at 6 PV panels, eight 6V batteries wired for 24 V. Add in the 4000 watt Inverter and 80 amp Charge Controller, cabling, DC Breakers, Combiner box, Lightening arrestors, and then the AC side, and I'm looking at almost $8000 US. And I'm doing all the work.

What might be a good alternative. CTC Has the Motomaster Eliminator Power pack Inverters. They go on sale regularly. They will supply 12V to 120V, and
have outlets you can plug into. And you simply plug it in to charge the battery pack.

In the camping section: They do sell 12V coolers. Get one of those and see how long it will run off the battery pack. They were designed for a weekend of camping, so it should run for a day or so.

If anything, it will help to keep your food from spoiling for a few days, while waiting for the power to come back on. You would have to test and see how long it runs, and decide whether you want to go that route and possibly buy another power pack to extend your run time for whatever amount of time you choose.

There are systems like this being advertised online. I think they are made by "Point Zero". They make systems for off grid and out back camping,
but are very expensive and limited.