Select the Right-Sized Generator for Your House
Posted by Tobias Sommer on Dec 12th 2023
Do you want to buy a new generator but aren't sure which size would work for your house? Here's a guide to selecting the right size generator.
A good percentage of American homes experience power outages each year.
According to the American Public Power Association, in 2015 about 90 percent of public utility customers had an outage. Time spent without power supply was around 63 minutes for each user. Such outages cause food spoilage, deny Internet access and put residents at risk.
Power Outages, Big & Small
Outages can be both localized and memorably widespread.
Some of the most severe power outages in the U.S. history include
- The Northeast Blackout of 2003 affected millions of people in eight states
- The Southwest Blackout of 2011 affected almost all of California
- The Derecho Blackout of 2012 affected 4.2 million people in 11 states and the District of Columbia
In 2015, customers of the Arizona Public Service Corporation (APS) had as high as an 82 percent chance of experiencing a power outage that'd last longer than 5 minutes.
Every year, the American power grid faces increased pressure. This has resulted in more power outages. In summer, because demand is constant, the demand placed on the grid is higher.
Causes of U.S. Outages
According to the American Public Power Association, wildlife is the leading cause of power outages. In 2015, for every 1,000 customers, there were 2.37 outages.
Other leading causes were:
- Overhead-equipment failure: 2.02 per 1,000 customers
- Weather: 1.38 per 1000
- Vegetation: 1.04 per 1000
- "Unknown": 0.76 per 1000
- Underground-equipment failure: 0.52 per 1000
- Other: 0.06 per 1000
- Human: 0.03 per 1000
- Vehicles: 0.02 per 1000
A portable or backup generator helps you avoid such problems. Let's talk a bit about how to choose a generator that’s the best size.
How Are Generators Sized?
We measure electricity in watts (W) and kilowatts (Kw). Since generators supply electrical power, they’re also sized in watts. A generator's size, in this regard, refers to the amount of electrical power it supplies.
You need to get the right size to avoid disastrous consequences. For example, if yours doesn't provide enough electricity, it could cause a voltage drop and severely damage expensive appliances.
If you choose one that's too big, the unit’s initial cost and ongoing operational costs could be burdensome.
How to Choose the Right Sized Generator
Here’s how to choose the right sized generator for your needs:
- Create a list of each appliance you want to power during a power outage
- For each appliance, list its starting and running wattage. Starting wattage is the initial amount of electricity required to start up. Usually, the starting wattage is 2-3 times the standard wattage in use
- Access a wattage worksheet here
- Total the wattage and multiply the number by 1.5. This is the least wattage your generator needs
Let's address your specific questions. Read on.
What Determines Its Size?
The answer to this is simple; the type and number of appliances which you want to power in case of a power outage.
What Appliances Do You Need?
It isn't necessary to compile the electrical needs of every appliance you own. Instead, which will you would need in an emergency? Those are the appliances to focus on. Portable generators, in most cases, can provide these needs:
Most houses need generators that can:
- Power the refrigerator and freezer for food preservation
- Recharge their phones
- Operate a computer or television
- Power some lights
You have the option to choose from portable or standby generators. Let's explore these options.
Portable Generators
As a cost-effective solution to power outages, portable generators ensure essential items like refrigerators, lights, freezers, sump pumps and space heaters continue to run.
For short-term needs, portable generators are useful for both emergency and spare time activities. They come in a range of prices. Many cost less than $1,000.
One other advantage of portable generators is they’re mobile. So they’re a good choice for camping trips.
Install a Manual Transfer Switch
During emergencies, portable generators come in handy. They are ready in three easy steps:
- Assure it has fuel or add some
- Start the engine
- Plug in your essential items.
Portable generators are also useful in powering recreational activities like outdoor parties.
But portable generators provide power to appliances through extension cords. But cords strung all over the house can be annoying, even hazardous. With a manual transfer switch, extension cords aren’t necessary.
The manual transfer switch lets you supply the generator's full power to your home's electrical panel. This lets you to support appliances that are hard-wired, like your well pump.
Once you decide which circuits to power, an electrician installs the manual transfer switch subpanel. They also fit a single inlet to power the subpanel. This way, you can power entire circuits, not just individual appliances.
In case of a power outage, you connect the generator to the inlet with cord, flip the manual transfer switch on the subpanel, and power your essential appliances.
With Generac portable generators, you can use either LP (propane) fuel or gasoline. Gasoline-run portable generators also can use inverters, which reduce their noise.
Rules of Use for Portable Generators
Do the following to ensure the safety of you, your family and your home and appliances:
- As soon as the power goes out, place the generator on a flat surface outdoors about 10 feet from your house.
- Ensure there are no canopies or carports in the immediate vicinity.
- Start the generator before you plug in extension cords.
- Extension cords should be at least 14-gauge for them to carry enough power. Use the cord's greatest wattage rating, which is found on the cord's label.
- High-wattage appliances can cause overloads. This would lead to tripping the breaker or blowing a generator's fuse, and damaging your appliances.
- Never turn the generator on inside your house or garage.
- Carbon monoxide poisoning is the leading cause of death among people using generators, more than the disasters which led to the power outages
- Plug in a carbon monoxide detector when you use portable generators. That way, if the generator's exhaust gets to a dangerous level inside the house, you can act swiftly.
- How long can it run on a full tank of gas? Consider that so you know if you have to waken to re-fill the tank.
Don’t Electrocute Utility Workers
It’s tempting to attach a second male end to a power cord and running it from the generator to the wall outlet to power a full circuit. But doing this lets generator power surge through the circuit breaker panel and into the utility lines. This can electrocute service personnel working on those lines.
Standby Generators
Standby generators are larger, more expensive solutions power outages. Propane or natural gas powers them. They come on immediately in cases of power outages, which makes them excellent options for people with frequent power outages.
Residential standby generators, including many of Generac’s, are priced between $2,600 and $5,000.
Standby generators are usually powerful enough to operate high-demand appliances like lights, central air and kitchen appliances, all at once. They’re hard-wired into your house’s electrical system so power hardly interrupted before the generator kicks in.
Unlike with portable generators, extension cords and noise are not bothersome. But to purchase a standby generator, transfer switch and necessary professional installation can be expensive. If you choose this option, take the cost implications into consideration.
Never Sweat Power Outages Again
The U.S. has a standing history of power outages due to various factors. If you factor in your household size, available budget, power requirements and local conditions, you can easily find the generator to meet your needs.
You want to live prepared!
Get a warranty to reduce your risk of loss in if the generator isn't as good as advertised. Apart from a sturdy generator, you should want cost-effective, professional installation. So don't wait until that bad storm looms to try to get a generator.
Get in touch with us today for all your generator needs.