If you are feeling frustrated by unexpected power failures, then you might be thinking of getting a backup generator for your home.
Introduction
How many watts does it take to run a whole house during a power outage? Do you need a 18kW, 25kW or a 35kW backup generator to provide power for everything in your house?
Before taking out your credit card, first take stock of what appliances are in your home and then calculate how many watts are needed when the power is down.
What features are important for a backup generator?
When searching for a generator that can power your house, you need to be mindful of features and functionality. You also need to find a unit that is large enough, yet still affordable. A generator is generally rated in terms of how much peak starting watts and continuous running watts it delivers.
Certain certifications are important. Look for a generator that is CSA, EPA and CARB certified. It should meet or exceed the standards for air quality in North America.
A low-oil shutdown system is essential for preventing possible engine damage due to insufficient oil. It seems like most generators have a built-in low oil shut-off feature. It should be easy to find a home backup generator with this safety feature.
Fuel economy is going to be an important thing if you need to power your house for a few days with a generator. A feature that might help with this is the fuel economy switch, or eco-throttle. This allows the generator to lower or increase its engine speed according to the amount of load that is currently being used. The economy mode decreases both fuel consumption and overall noise level.
Another important feature is an overload protection system that will protect the generator and appliances in case of an overload.
A portable generator that is large enough to power a house is going to be heavy to move around. In that case, a wheel kit will make it easier to move the generator around, especially if you are on your own.
Inverter technology provides clean power for sensitive electronic appliances such as a flat screen television, gaming console, desktop personal computer or mobile notebook computer. If you want to power such electronic devices during a power failure, then an inverter generator is a good choice.
How much wattage do you need to power a house?
Certain appliances in your house are power-hungry while others are not. You need to carefully consider which equipment is essential and which are not. Moreover, think about which appliances are going to be running at the same time. In addition, some household appliances use more power when they start compared to when they are in operation. Check each appliance and make notes of the wattage printed on the label or in the product manual.
If a device shows only the amount of amps required, then you can still calculate the wattage. Do this by multiplying the amps with the voltage, e.g. 10 amps multiplied by 120 volts equals 1200 watts.
You should calculate how much wattage is needed so that you can choose a generator model that delivers enough watts. This way you might avoid the frustration and disappointment that is the result of buying a generator that is just too small to power your house in an emergency.
Here is a list of household appliances that you might use during a power outage:
- Air Conditioner
- Ceiling Fan
- Clothes Dryer
- Coffee Maker
- Computer
- DVD Player
- Electric Space Heater
- Electric Toaster
- Freezer
- Furnace Fan
- Gaming Console
- Incandescent Light
- LCD Computer Monitor
- LCD Flat Screen TV
- Microwave Oven
- Refrigerator
- Sump Pump
- Washing Machine
There might be other items that are specific to your household that you can add to this list. Remember that you need to take into account both the running wattage and the additional starting wattage of certain appliances.
Can I use a portable generator to power my house?
The key benefit of using a portable generator for powering your house during a power failure is the cost. It is cheaper to use a portable generator compared to installing a home standby generator.
The simplest way to use a portable generator for home backup power is to run it outside at a safe distance and then connect a few essential appliances by way of extension cords. If you want a safer setup, then you can connect the portable generator to the electrical panel of your house with a transfer switch.
The downside of using a portable generator for home backup power is that a lot of them use gasoline as a fuel source. However, there are a few dual fuel portable generators on the market that can also run on liquid propane fuel.
Another disadvantage is that these generators are heavy to move around: because of that a wheel kit is an essential accessory. Furthermore, even the largest portable generator might not produce enough surge watts to power a whole house. You will have to carefully manage appliance and power usage to avoid overloading a portable generator.
Is it possible to use an inverter generator for home backup power?
An inverter generator is generally used for outdoor activities such as camping, tailgating, hunting or powering a recreational vehicle. However, it is also useful for powering sensitive electronic equipment such as televisions and computers. However, the majority of these inverter generators fall into the 1000-watt to 3000-watt category, although there are a few models that produce more wattage.
For example, the Honda EU7000iS is a portable inverter generator that produces 5500 continuous running watts and up to 7000 peak surge watts. In light of that, a recreational inverter generator is probably too small to provide backup power for a whole house. Nevertheless, it might work for running a few sensitive appliances if you do not use a well pump or a central air conditioner.
Tips For Managing Household Power Requirements
The most important tip is that you should never try to start all the appliances at the same time. If you do that, then you are going to need a big portable generator or an even larger whole house generator.
Instead, start appliances that use additional surge watts at different times. For example, do not start the central air conditioner, washing machine and sump pump simultaneously.
Another tip for managing power requirements is to remember that some appliances do not need to be on all the time. Only use the devices that you need and turn it off when not in use.
Home Standby Generator For Running a Whole House
A more permanent and convenient solution to the problem of home backup power is to install a stationary home standby generator. Then you will not have to worry about moving a portable generator out of storage and struggling with extension cords. However, buying and connecting a home standby generator to your household’s electrical system is a significant investment and should be done by a qualified electrician.
A home standby generator usually runs on either liquid propane (LPG) or natural gas, so you never have to carry around and refill gasoline cans and fuel tanks. Such a generator has the ability to back up your entire home during a power outage. It might even be able to turn on automatically after a power failure to provide backup power for your house until normal power is restored.
A transfer switch is an essential component that makes it safe to switch between the utility power and the backup generator power. These switches operate either manually or automatically.
The person in charge of installing the home backup generator should consider a few things such as the required wattage of the generator, the best location, the fuel line, transfer switch and electrical connections. This person will also test the generator so that it is ready to go when the power is low.
The Size And Cost Of Home Standby Generators
The calculation of the wattage and installation costs of a home standby generator should be done by a qualified electrical professional. The costs will be modified by where you live, the size of your home and the estimated cost of installation. Moreover, a home that uses natural gas appliances consumes less electricity compared to a home where there are only electrical appliances.
For example, say your home is about 2500 square feet, and you want to provide back up power for the entire house. You might have to get an 18kW to a 24kW automatic home backup generator that is going to cost about $5000 or more. To this you have to add the cost of shipping, taxes, the transfer switch and installation. The installation costs alone could be at least $2000 or more. For that reason you have to do your homework very well and get professional advice before you buy and install a home standby generator.
What size generator would you need if you had an even larger house of more than 5000 square feet? Then your house might require a whole house standby generator of between 25kW and 35kW.
How To Decide What Size Whole House Generator To Buy
It is very important to know the exact starting surge wattage and rated running wattage of every appliance in the home. You will need this information to calculate how much power your household consumes and what size standby generator is required.
When it comes to home backup generators, size does matter. If the generator is too small for the house, then it might overload, overheat and burn out. Conversely, if the generator is too large, then you will spend too much on installation and operation costs. In light of that, how do you decide what size generator you should buy?
First, make a list of all the appliances in your house and yard that requires power.
Second, collect the starting surge and rated running wattage of everything and add it to the list.
Third, use your brain or a calculator to add up all the numbers. Keep the surge and rated watts in different columns and add them up separately to get the total wattage amounts for each column.
Fourth, look at the total surge wattage because this is the minimum size backup generator that your home will need.
For example, the total starting surge wattage is 22000 compared to a total running wattage of 13000. This means that you will need at least a 24kW home standby generator or larger. You should always leave a little headroom to prevent an overload.
Of course, this is a rough and ready way to calculate the size of a generator for powering your whole house during a power outage. If you are serious about installing such a generator, then you should get a qualified electrician to do the calculation for you.
Photo by R ARCHITECTURE on Unsplash.