Portable generators let you take power where you need it, when you need it. People use them while camping or RVing, and many contractors use portable generators on job sites where there is no power. These are all great applications, but don’t overlook their usefulness in an emergency. Portable generators for emergency use help keep essentials working and protect your home and your food supply during a power outage.
Emergency Generator Use
When the power goes out and stays out, don’t wait too long to start the generator. Your main objective is to keep sump pumps, refrigerators and freezers working, and possibly add a few lights. In the absence of standby home generators, portable generators will supply a limited amount of power as long as they have fuel. Purchasing fuel during a power outage might be a problem which makes having fuel on hand essential. Gasoline, propane and diesel fuel are the most common fuels used.
Load shifting is a practice used when there are too many appliances for the generator to power at one time. Plug in the freezer, let it run for a while, then switch to the refrigerator. Keep an eye on the sump pit and plug the sump pump in when it begins to fill. If your sump has a battery backup, you can use the generator to recharge the battery.
Generators cannot supply an unlimited amount of power. Power, expressed in watts is the voltage multiplied by the current. A device that draws 10 amperes of current at 120 volts uses 1200 watts of power. If the generator can only supply 1000 watts, any device that requires more than that will not operate, or will operate at less efficiency and may be damaged.
Motors use more power when they start, and large, heavy-duty motors can draw a lot of power in the first three second of operation. Be sure your generator will supply enough power to start a load, as well as keep it operating. Understanding how to determine generator sizing will help you choose a portable generator for emergency use.
The generator’s fuel capacity is another limitation and the ability to operate for extended periods during a power outage is important, especially if you’re trying to keep the refrigerator or freezer cold. You don’t want to run out in the middle of the night to fill the generator, or worse, go looking for a gas station to buy fuel from.
There are two ways to connect a portable generator. The first requires no changes to a home’s electrical system. Plug in a few long extension cords and you’re ready to go. The appliances plug directly into the cords, so everything that generators power must have a cord with a plug. This method won’t help with built-in lighting or anything that does not have a plug. It does work well for refrigerators and freezers, sump pumps and most other small appliances.
A second option is a manual transfer switch that connects to the portable generator with aheavy duty cord. A transfer switch selects the power source―either the utility supply wires, or the portable generator. The switch has a circuit breaker for each circuit it will supply. During a power outage, the generator is started and plugged into the transfer switch. The switch is moved to the generator position and the circuits within the switch have power.
You might read how some people will connect a generator to their homes by back-feeding their electric range or electric dryer outlets. This is not an acceptable practice and if done incorrectly, can endanger the lives of utility company employees working to restore power in the neighborhood. Don’t do this.
The safest solution to bring power from any generator into a home is a transfer switch. The loads are kept within safe levels by the circuit breakers in the transfer switch. The transfer switch also keeps all the loads properly grounded, yet another safety factor.
Ensure that any extension cords used have wires designed to carry the load they are connected to. A 100 foot extension cord with 14 gauge wire should not carry more than 12 to 15 amperes. Plan ahead and have the extension cords you need on hand.