Natural gas powered generator.
Solar will only run a light bulb.
Propane.
I would never rely on solar energy. The sun hasn’t shined here in a week. If you only need to run a refrigerator and freezer you only need a 2.5 or 3.5 kw generator. If you have natural gas use that. If you don’t get a propane tank. Gasoline will go bad and it has all that alcohol crap in it.
Bfl.
I have one of these and it works very well.
http://www.gepower.com/prod_serv/products/nuclear_energy/en/index.htm
And, if you go with gas and don't want to be chained to public supply, be sure you know the compatibility of generator and fuel tanks.
(A friend is going through fits after reading fine print on what tanks her generator will deal with.)
Also, consider where you live and how quiet the gen has to be: quiet is costly.
There is a company that provides multi-fuel conversions for most generators but I don't know how well they work. Same company offers very expensive factory converted jobs.
Finally, wherever you live, if you go with gasoline be sure you know how long the stuff they sell in your market will store.
(I'm in SoCal & have to load up with Sta-Bil or something like it just to leave a car in the driveway for a week or so - that applies to carburettors far more than to fuel injection and your generator will have a carb.)
If it is really backup, then propane.
Gas goes bad pretty quickly. Diesel also goes bad over a longer period but still goes bad.
Natural gas is dependent on the utilities to provide it. Debatable in a true emergency like an earthquake. Natural gas also has less energy per unit volume so generators generally produce less when compared to propane.
You can bury a large propane tank making it very robust, particularly in an emergency.
If the purpose is more than backup then diesel. Diesel engines are more reliable and last longer with less maintenance. If it is regularly used the diesel fuel will be consumed before it goes bad.
Generac propane 18kw - big tank ! Power has gone out for more than a week before during ice storms in NH
Saved Christmas Eve family gathering one year....
Another thing, storage of large amounts of gas or diesel (hundreds of gallons) is very difficult these days due to all the permits and inspections required. Even more difficult to put underground, at least legally.
Propane is much, much simpler. If it leaks there isn’t an issue with soil contamination. So the requirements are far less for a large storage tank underground.
I have a 500 gal. underground propane tank for my standby generator...
You have to be careful with electronics. For things like a computer / HDTV and receivers you need a clean sine wave. Generally those are done with inverters. Most R/V folks buy a Honda or something of that caliber. They cost about 3 - 4 times what a normal generator costs but they don’t have a lot of capacity.
For normal household stuff (that used to be the case before everything went digital) a regular generator was fine.
Forget solar, it is good for a few lightbulbs for a couple of hours. It's basically a battery backup like used on computers with a solar panel to charge the batteries. If you check out their wattage, they range from a few hundred watts to maybe 1500 for a large beast. You have battery maintenance and very little power. Even a large one wouldn't run you freezer for a couple of hours.
Figure out what you want to run and add up the amps. The look for 5000 watts for every 30 amps of 110volts usage. If you want to run air conditioners, get ready for big bucks and something in the 12-15kw range. Very few solutions would run everything without giving up something. I have 5kw gasoline for hurricanes and it barely runs a few lights and my refer and freezer. It also takes about a 5 gal can of gas a day, so at $4 a gallon, well you get the point. I have been thinking about converting it to nat gas for about 5 years, so you see how much I worry about it.
Forget solar, it is good for a few lightbulbs for a couple of hours. It's basically a battery backup like used on computers with a solar panel to charge the batteries. If you check out their wattage, they range from a few hundred watts to maybe 1500 for a large beast. You have battery maintenance and very little power. Even a large one wouldn't run you freezer for a couple of hours.
Figure out what you want to run and add up the amps. The look for 5000 watts for every 30 amps of 110volts usage. If you want to run air conditioners, get ready for big bucks and something in the 12-15kw range. Very few solutions would run everything without giving up something. I have 5kw gasoline for hurricanes and it barely runs a few lights and my refer and freezer. It also takes about a 5 gal can of gas a day, so at $4 a gallon, well you get the point. I have been thinking about converting it to nat gas for about 5 years, so you see how much I worry about it.
We had a 17kw Generac standby generator installed last fall - our water heater, clothes dryer, cooktop and furnace are all propane so the generator is piped into that same system from our 500 gallon tank. If our grid power goes out for more than ten seconds, the gen fires up and runs everything. It starts itself once a week automatically for fifteen minutes as a self-test, change the oil once a year on the two cylinder four stroke 900cc engine.
Price was a little over 10K plus tax.
Seems like you would not have to run it for more than a couple hours each day to keep things frozen.
During the outage after Ike, I ran our fridge off of a 1000W generator averaging about 12 hours/day for 17 days. It powered some lights, a couple of TV's, a battery charger, my laptop and modem.
It will take a modern fridge about 4-6 hours to go from warm to cold on the first day, then it will take a couple hours to regain what it lost overnight, and cycle on and off as needed.
What I did was run the frige during the day with the thermistat wide open, then leave it closed over night. I had some small 10AH 12V batteries for cooling fans at night.
A small efficient generator can do that on about 2 gallons/day. A larger one will pull more appliances, but it will use more fuel.
As for alternate fuels, you can buy larger wattage generators setup to run on NG or Butane, or you can buy an aftermarket kit to convert most any generator to them.
Solar is iffy, as is wind. A generator is much more reliable when you are talking about food storage.