Should I buy a Generator or Battery Bank?

The answer could be “Yes” or “It Depend”.


Minimal System – If you are looking for a minimal system that only supplies basic needs as outlined above, a simple single battery system would work fine.

The least expensive way to provide power during an emergency is attaching an inverter to your car battery. I suggest a Cobra 800 watt inverter from for $48. I did an article on the blog about it. You can go to if you want to read the info.

The next step up would be to buy a 125 amp hour battery from Sam’s Club for $90 and a Schumacher XC12 12 Amp Battery Charger from Amazon for $44 (I would buy a Schumacher XC103 30 Amp Battery Charger for $78 if you plan on adding a second or third battery to your battery bank) and use it in combination with your inverter and car battery. This is how I would use this system in an emergency.

If you use the inverter attached to your car battery, you’ll need to run an extension cord from the inverter to inside the house. Sometimes that may not be convenient.

Better would be to have a marine battery inside the house on a table or countertop to run all of the small items you need to run during the day and to run your lights at night. Many small items use USB outlets to recharge. I would buy a cigarette lighter adapter that hooks to battery and a USB adapter that plugs into the cigarette lighter to charge all my USB items. Hooking these items directly to the battery for recharging will use less energy than going through an inverter to charge them. If you have multiple items to charge at the sometime, you can buy cigarette lighter adapters that have multiple outlets and USB adapters that have multiple plugs.

You can also attach your inverter to this inside battery to run items that don’t use much power but need   115 volt power. I would use this inside battery to run any item that uses less than 100 watts or is used for a short time.

Once a day I would hook the inverter up to the car battery and run an extension cord into the house to run the high wattage items. Start your car and let it idle in a well ventilated area. Your car must be started before plugging anything into the inverter. Use this time to use the bread maker, rice maker, wheat grinder and lap top. In addition I would plug in my Schumacher battery charger and recharge the inside marine battery at the same time. You should be able to bake your fresh bread, do essential work on the computer, make a batch of rice and recharge your battery in 1 hour a day. Idling your car for 1 hour will use about a half gallon of gasoline.  Doing this for 2 weeks would only use a half a tank of gasoline. Always keep your car’s gas tank at least half full.


Moderate System – The least expensive way to build a system that will supply more emergency power is to add an additional 125 ah battery to your battery bank and run more high wattage items, like a furnace fan, off of your car battery and inverter. Two batteries hooked together will provide 1500 watts of usable power.

If you use natural gas to heat your home then being able to run your furnace during a winter power outage will make a real difference in your comfort. I’ve written an article on the blog about it. You can go to if you want to read the info.

You’ll need to hook the two marine batteries together. You do this by connecting the positive terminal of one battery to the positive terminal of the other battery and by connecting the negative terminal of one battery to the negative terminal of the other battery. You’ll need to use at least 6 gauge cables. I’d suggest larger gauge cables if you plan to add more batteries and have a 3, 4 or 5 battery power bank. You can buy the battery connection cables at Wal-Mart for around $8 each.

When your house gets cold and you need to run your furnace, hook the inverter up to the car battery and start your car and let it idle in a well ventilated area. Your car must be started before plugging anything into the inverter. Run an extension cord into the house to run your furnace.

At the same time, run another extension cord to your battery bank charger to keep the battery bank fully charged. This is probably the most your 800 watt inverter can handle. If you wanted to run your bread maker at the sometime you would need to get a 1500 watt inverter to handle everything at once.

How cold it is will determine how often you need to turn your car on to warm your house. I’d run your furnace until your house is up to a reasonable temperature, about 66-68 degrees. Then turn off the furnace, unplug the extension cord and turn off the car. When the house temperature dips to 58-60 degrees, then start the furnace again. In cold areas I’d figure needing to run your car up to 5 hours a day. This would use 2.5 gallons of gasoline each day. A full 16 gallon tank of gasoline would last 6 days. A half a tank of gasoline would last 3 days. Always keep your car’s gas tank at least half |full. If you want to prepare to have emergency power for longer than 3 to 6 days, you’ll have to store some additional gasoline for your car or have an additional car.

Use your battery bank to power everything that uses less than 100 watts. Just make sure to do some battery bank recharging every time you turn on your car. Remember I said to buy a battery charger that could recharge your battery bank in 5 hours. The reason I said 5 hours is that is the reasonable time you could run your car and inverter each day to run high wattage items.

You probably have noticed that we are using your car as a generator. At some point you may want to consider buying a generator to run your furnace motor and other high wattage items.

You will definitely need a generator if you want to get closer to normal during an emergency.


Close to Normal – The close to normal scenario uses 4900 watts of power each day. Your car with an inverter and a 2 battery power bank cannot sustain that much power draw for more than one day. It’s time to buy a generator if you want a near normal life.

There are a lot of Made In China generators that would have a hard time making it through a single one week power outage. Do your research and don’t buy the cheapest one you can fine. I am going to suggest two specific generators. One good generator that is well priced and then the best generator made that is expensive but worth it.

The good well priced generator is the WEN 56352 3500-watt 208cc 7 HP OHV Gas Powered Portable Generator, With Wheel Kit. 3500 peak, 3000 running watts, 4 Gallon fuel tank with fuel gauge, 11 hrs. Run time at half load. I own this generator, it runs great on gasoline. I put a tri-fuel conversion kit on it and use it with natural gas and propane. Currently $340 shipped from Amazon.

The best generator is the Honda EU2000i Inverter Generator. This is by far the best generator available today. I understand that because of the price this generator is not for everyone. It costs $ 1000 and you have to look around a bit to get that price, but you will buy and wear out 2 or 3 $350 generators before this one wears out.

It is super efficient on fuel. It only has a 1.1 gallon tank but it will run 10 hours on that 1.1

gallons. It is quiet, less than 60 db. Output is 1600 watts continuous and 2000 watts peak. With   10 gallons of gasoline and running it 8 hours a day, you could go 2 weeks with this generator. If I could only have one generator, this would be it.

Use your generator to run your high wattage items. You may want to run some really high wattage items like a coffee maker and a microwave one at the same time. This shouldn’t be a big deal.

The biggest key is to use your generator as little as possible to conserve fuel. When you do use it, use it as much as possible. Run all the high wattage items you need to run while the generator in on and be sure to charge your battery bank every time you run your generator. Continue to run items that need 100 watts or less off of the battery bank. Run high wattage items off the generator.


Backup to the Backup – If you want to add some redundancy to recharging your battery bank, you could consider some solar panels. Solar Panels are only a good idea if you live in a area that gets a good number of sunny days.

Consider buying 100 – 150 watts of panels for $150 to $200 and a charge controller to handle them for about $35. Since the solar panels will only work in the day which is when we also will be using power, I’d separate your two batteries. I’d have one outside being charged by the solar panels and the other one inside running our low wattage items. Each day I’d switch them so the charged battery is inside being used and the other battery is outside being charged.

In a long-term emergency if you ran out of gas to run your car or generator, you could still have power to run your essential items.


Ed Rogers
Copyright “Keep It Simple” 2013. All Rights Reserved.

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