When buying a generator, the goal shouldn’t only be to achieve backup power. Instead, it should be about having sufficient backup power to manage the way your house runs during an outage. This is where permanently installing a standby generator is beneficial, if you choose one that’s properly sized. If the generator is too small, it will struggle to keep up. A generator that’s too large will cost you more than is necessary. There are details to consider that help answer the question of “What size generator do I need?”. It’s important to rely on a knowledgeable team with experience to help you make a final decision.
Why Generator Sizing Matters More Than Many Homeowners Realize
Choosing the right size generator depends on what your specific goal is regarding what you want to power during an outage. Some homeowners may only want to keep essentials running, such as AC/heating, refrigerators, freezers, and lighting. Others may want their generator to provide coverage for the entire house. Sizing can have a direct impact on key areas, including comfort, reliability, fuel use, and installation cost.
Make a List of Major Appliances and Systems
The first step in generator sizing for a home is to go through your residence and make a list of all the equipment you’d expect to run to use during an outage. Grouping the different loads into some of the categories in the list below makes it easier when you are estimating your wattage needs.
- Heating and cooling
- Kitchen appliances like the stove, oven and refrigerator
- Water heater and other water-related equipment
- Lighting
- Electronics
- Safety and medical needs
Pay Attention to Starting Wattage, Not Just Running Wattage
Some of the equipment in your house requires a big surge of power when it first starts. That power requirement will drop during normal operation. This is common for appliances with motors, such as air conditioners, heat pumps, refrigerators, freezers, washing machines, and dryers. Adding up the loads of all your appliances isn’t enough to give you an accurate estimate. Avoid focusing on the running wattage instead of taking the starting wattage into account. Otherwise, the generator likely won’t produce enough power to meet your needs.
Practical Ways to Estimate the Right Generator Size
You should always get help from a professional to calculate your electrical load when shopping for a generator. However, you can consider these basic steps beforehand to make it easier to estimate which generator size will best meet your needs.
Review Appliance Labels or Manuals
Focus on your essential major appliances and their load requirements. Most appliances should have a label that tells you the running wattage, and some may list the starting wattage as well. This information is also listed in the user’s manual, which you should be able to find online if you no longer have the original copy.
Use the Electrical Panel as a Clue
Looking at your electrical panel can also help you determine the wattage requirements on your essential major appliances. Most of these appliances are on a dedicated circuit. The amperage of each of the circuit breakers allows you to calculate the maximum wattage draw of each appliance. To calculate watts, you need to multiply the amperage of the breaker by the voltage of the circuit. Appliance circuits with a single-pole breaker are 120 volts, and circuits with a double breaker are 240 volts.
Decide Between Essential-Circuit Backup and Whole-Home Backup
Finding a home generator depends on your power goals. You can save money on a smaller generator if you only want to have backup power for your essential circuits. Essential circuits generally mean the HVAC system, major kitchen appliances, and the outlets and lights in areas like the kitchen, bathroom, and living room. A whole-home backup generator will be more costly. However, it will ensure you can use everything in your house during an outage.
Signs a Generator May Be Too Small
One thing you always want to avoid is having to choose which circuits to power and what to run during an outage. A generator may still be somewhat useful if it’s too small. However, an undersized generator doesn’t offer good value for your money since it doesn’t provide the meaningful protection a household needs. One concern is that the generator may get overworked during a long outage or bad weather. This can lead to it breaking down or shutting off because it’s overloaded.
It’s inconvenient to have to prioritize what to run during an outage. You likely have too small a generator if there isn’t sufficient available power for key appliances to start smoothly and reliably. Lights dimming or flickering when larger equipment like an air conditioner or heat pump turns on can be an indication that your generator is too small.
Problems a Too-Small Generator Can Cause
Installing a generator that’s too small can carry real consequences, including overloaded operation, frequent shutdowns and breakers continually tripping. The biggest worry is the impact it can have on your comfort if you’re not able to run your air conditioning or heating when you need it most. An undersized generator also experiences more stress, which can lead to frequent repair needs and a much shorter lifespan.
Problems a Too-Large Generator Can Cause
Many homeowners make the mistake of installing an oversized generator because they choose out of fear of not having sufficient power. Instead, the focus should be on load requirements. Choosing a generator that’s larger than what you need means overspending on the equipment and installation. Your operating costs will also be higher with a generator that is too big due to the equipment using more fuel.
When DIY Estimates Stop Being Reliable
While you may be able to make a somewhat accurate estimate of your load requirements on your own, there are situations that call for an expert. If your home has central air conditioning and/or multiple large, high-demand appliances, consult with a professional. Other considerations include whether your electrical panel is older or difficult to understand or you want the generator to provide whole-home coverage. Scheduling professional outage planning is essential for managing your comfort and any important medical or business needs.
Why a Professional Load Evaluation Gives the Best Answer
A professional load evaluation and calculation always provide the best results. An experienced professional can review your electrical load, focusing on essential circuits and major appliances, startup demands, and your desired backup power goals. From there, they can recommend a system that accurately fits your home. At Call Climate Services, our team walks homeowners through the entire process of selecting a correctly sized home generator. We provide a full range of generator services, including installation, repair, and maintenance throughout Northern Salt Lake Valley and Davis County, UT.
We offer a range of quality home generators from trusted brands, and you can rely on us to reliably see to your backup power needs. Contact Call Climate Services or schedule online for a professional evaluation, generator sizing recommendation, and installation guidance to ensure you choose a reliable backup power option with confidence.
