Backup Power

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Backup Power for Your Home, Office, or Remote Location’s Critical Loads:

A backup power system is ready 24 hours a day to instantly provide clean, quiet, automatic backup power.  Our mobile solutions are designed to make the addition of a backup generator, or battery backup relatively simple. This winning combination is great insurance against extended power outages, ideal for powering remote sites and a must for folks who want to live a more sustainable “off grid” lifestyle.

When planning your back-up power system, be aware that the back-up power must be sent to a sub-panel that is not directly connected to your main AC service panel.The two panels may be connected through the inverter in the battery back-up system.You will have an AC line coming from your main service panel which is connected to the “AC in” on the back-up system.The “AC out” is then sent to the sub-panel only, not back to the main panel.During a power outage, power will be supplied only to the backed up sub-panel, not to the main panel. This requires that you relocate specific circuits that you wish to have powered when the grid is down, to the new sub-panel. This is best accomplished by a licensed electrician.

The reason for this is twofold. First, if you were to send the “AC out” from the back-up system to your main electrical panel, you would be back-feeding (down) into your local neighborhood electrical grid. This is illegal and dangerous. Secondly, when the electrical grid is (up), power will be flowing, unregulated, back through the “AC out” connection on the back-up system and could damage your electrical system.When the emergency system is running, power will flow from the main panel through the battery back-up system to power the loads / circuits in the sub-panel you chose. This power is limited by the power transfer capability of the inverter. If you need more current transfer capability for your backup up loads, you can parallel multiple inverters to increase the current flow.

Two questions to ask yourself are:

1) How many watts does it take to power basic items I will need in an emergency?  Essential items will average 3,000 to 5,000 watts of power to run.

2) Do I know the difference between running watts and starting watts?  Running or rated watts are the continuous watts needed to keep items running such as lights, TV’s, radios, electronic device chargers, and fans.  Starting watts are the burst of energy needed to turn on something quickly or for a short time, like a blender, microwave, or hair dryer.

Power Requirements:

Emergency back-up batteries provide 24/7 blackout protection to supply power during a utility outage. Decide whether you want to back up a few essential circuits/outlets or your whole house or business. The number of circuits you back up and the power requirements of the items on those circuits will determine the quantity of batteries you need.

It’s very important to calculate the power output you need and to give yourself some wattage cushioning for running a few smaller items if need be. If you have the owner’s manuals for the appliances and equipment that you want to run, find and add up the start-up wattages for each item. Otherwise, use the chart and formula below to estimate your power requirements.

Broiler1,400Personal Computer500-2,000
Central Air Conditioning2,000-4,000Planer300-900
Chain Saw1,000-1,800Refrigerator/Freezer600-800
Circular Saw1,200-1,600Router100-1,300
Coffeemaker400-800Sanders (belt, disc, orbital)250-1,500
Drills (depends on size)250-1,200Shop Vacuum700-1,400
Electric Furnace5,000-25,000Space Heater1,250
Electric Range (oven only)5,000String Trimmer600-1,100
Electric Range (one element)2,500Sump Pump1,500
Hair Dryer1,200-1,500Table Lamp (tri-lite)150
Heater (radiant)1,300Television100-350
Hedge Clippers300-1,0003/4 HP Paint Sprayer1,800
Hot Plate1,250Toaster1,100-1,700
Leaf Blower1,000-1,400Water Heater3,000-4,500
Microwave1,200Water Pump1,000-2,000
Miter Saw500-1,000Window Air Conditioner600-1,500
Outdoor Lighting500-1,000
* This is approximate wattage only. Please refer to your appliance’s owner’s manual for exact wattage.

Running Watts:  Total your equipment’s wattage requirements from the chart above.  Overtaxing a battery or inverter reduces efficiency and in some cases can damage connected equipment. It’s very important to calculate the power output you need and to give yourself some wattage cushioning for running a few smaller items if need be. If you have the owner’s manuals for the appliances and equipment that you want to run, find and add up the start-up wattages for each item. Otherwise, use the chart and formula above to estimate your power requirements.

Starting Watts:  Multiply the total wattage requirements by two, to determine the wattage necessary to start equipment with motors.  Start-up requirements may be as high as three or four times the running requirements, so it’s best to check owner’s manuals for exact wattages; portable generators offer a higher surge wattage to help accommodate start-up requirements.

For more information about:

Portable Battery Backup Power Click Here

Solar Charged Batteries Click Here

Backup Generators Click Here

Watts Used By Average Appliance Click Here

A note on the future of intense storms

Intense winter storms can leave you with several feet of snow and no power, water or heat. A passive solar house with a grid-tied solar electric system works great when there’s sun.  It doesn’t work at all when the utility power is down.The first couple of days with no power you might be okay. You can move stuff from the ‘frig to a cooler out in the snow. Your house might even hold its heat pretty well, and you could cook on the propane fed kitchen stove. But by the third day of no power, the bedroom temps can get to around 40 degrees at night. Brrrrrrrrrr! Unlike many of the homes in your area, you may not have a wood-burning stove.  Most hydronic baseboard heaters rely on electricity to power a pump. So it is time for action!


A good place to start would be a heavy-duty 200 amp hour 6-volt DC batteries.  Pick up six UPG batteries and a Magnum sine wave inverter/charger.The UPG’s are sealed batteries so no need most likely to have to worry about off gassing. The inverter’s job is to convert the DC electricity coming from the batteries into AC electricity, which can power our house. Magnum inverters/chargers are really smart; they can charge batteries from grid electricity or from solar panels or from a gas or propane generator and then feed the electricity right where you need it.

You could also wire your house to add a battery back up system later. You could separate out the essential appliances you want to be able to power in emergency (this is called the critical load) … and includes things like: the water pump, the heater pump for your hydronic baseboard heaters, and the electrical outlets in your office so you can run computers and phone. But you can just as easily run a cord with multiple plugs from the backup power unit.  Refrigerators and electrical appliances with heat elements are huge energy draws and so it is probably best to not plan to power them in an emergency.


It will probably take you about an hour to wire the batteries into a 12-volt configuration, connect them to the inverter/charger and run a wire to our breaker box.  Flip the switch and, bingo, the water pump started refilling the pressure tank, the heat pump started up, and the house heated up. You could run the essential appliances for the next two days simply on the energy from the batteries, without recharging them. If the power had been out for much longer you could have charged them with solar panels or with a gas generator.Solar panels may be the way to go since many people really don’t like the idea of using a gas generator because they are messy, unreliable and hard to start (unless you spend really big bucks), and they depend on a non-renewable fuel that is in limited supply here during extreme weather conditions.A permanent solution for our battery backup systems that can include a Magnum Sinewave inverter and UPG sealed batteries in a slick attractive cabinet.  Most of us can find room in a closet near the breaker box to put it in.


Lastly, you could mount a battery monitor on the wall in a hallway so you can keep an eye on the battery charge.  Batteries are kept charged by grid power.  If power is out for too long you would then use solar panels to charge the batteries via an AC Coupled Battery Backup System that can use a grid-tied solar modules and micro-inverters to charge your batteries and run your loads when the grid is down.

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