What size generator will run a house?

Choosing the right home generator is very important and the first questions most often asked are, how big of a generator do I need? What size of a generator do I need for my house? What generator size is enough to run a refrigerator and freezer? How many watts do I need to power my MIG welder/sump pump/air compressor? These are all critical questions to answer before proceeding with buying a home generator. This is because too small a unit may not be able to handle a central air conditioner or keep the pumps running. Using too large of a generator will be inefficient and wastes fuel eventually.

In order to determine what size generator you need to power your whole house:

1. Firstly, figure out the starting wattage (i.e. “surge” wattage) of the appliances and fixtures you want to power.
2. Find a generator powerful enough to exceed the combined wattage of everything that needs electricity.

In this article, we’ll guide you through the process in more details below. But first, we are going to be taking a look at how generators are sized.

How Home Generators Are Sized

The size of a generator is determined by its electrical output rather than its physical dimensions. They’re measured in watts (W) or kilowatts (kW), which are both units of electrical measurement (1kW = 1,000W).

The capacity of generators is measured in kilovolt-amperes (kVA). The kVA is a measure of apparent power that indicates the entire amount of power consumed by a system. kW Equals kVA in a 100 percent efficient system. Electrical systems, on the other hand, are never 100 percent efficient, therefore not all of the system’s apparent power is employed to create useful work output.

If you know the electrical system’s efficiency, you can convert between kVA and kW. The more effectively the kVA is transformed into useable kW, the closer the power factor is to 1.

Generators have a power factor of 0.8, according to international standards. When matching the size of your load to a generator, power factor is critical: a generator rated at 100kVA with a power factor of 0.8pf will be insufficient to power equipment that requires 100kW of real power.

As a result, selecting the appropriate generator size is critical.

You might wonder why. If you acquire a generator, that is

• Too small, it will overload or be forced to give more power than it can manage. If this happens, the generator will either shut down or overheat, frying both the generator and your expensive equipment.
• Too large, you’ll overpay for both the unit and the cost to operate it, which basically means you’re wasting money and resources.

Now, let’s look at how to figure up what size generator your home need.

Determine what size home generator you need in just 3 simple steps

To calculate what size generator you need to power your whole home, follow these 3 steps:

• Step 1: Start by making a list of the most important circuits in your home. These include refrigerators and freezers, central air and furnace, sump pumps, well pumps, and medical equipment.
• Step 2: Determine the starting and running wattage of everything on your list. If you can’t find these numbers on the appliance label, you can use this

Note: Starting wattage (sometimes known as “surge wattage”) is the amount of power required to start an appliance. The starting wattage of an appliance is usually 2-3 times larger than the “running” wattage, or how many watts it requires to operate continuously.

• Step 3: The generator size is easy to pick once you know the approximate power required. Choose a generator with a capacity that is 10-20% more than your demand, whichever number you come up with. This will provide you some flexibility or room if you decide to upgrade your equipment and find that you require additional power as a consequence. It also aids in the management of “de-rating,” or the generator’s underperformance compared to its manufacturer’s declared capabilities owing to harsh operating circumstances such as high altitudes or severe temperatures.

Note: Always remember that a DIY wattage estimate is just that: a guess. To be safe, use a wattage calculator or, better yet, have a professional electrician determine the precise wattage you require to assist you in selecting the appropriate generator size.

If you’re up for trying it yourself though, let’s look at a couple examples.

AirPlus includes a Free 10 Year Parts & Labor Warranty & One Free Year of Generator Maintenance with 24 Hour Off-Site Monitoring With Every New, Installed Fixed Generac Generator We Sell!

Using A Home Generator To Power Your Essential Circuits

If you just want to power the “essentials,” your list may look like this:

Based on this load calculation you would need a generator in the 25kW size range to support the items listed above, since the starting wattage is 24kW.

Now, you may be thinking “I don’t need a 25kW generator because I am not going to be running all of these items at once . . . a 15kW would do just fine”.

Even if you plan to use these appliances one at a time, a correctly sized generator expects that everything connected to it will be running at the same time.

The National Electrical Code (NEC) modified the rules for the installation of fully automated generators in 2008. Prior to the 2008 NEC, it was permissible to install a backup generator if the homeowner agreed not to use heavy power equipment at the same time. Automated generators must now be sized to handle the whole load connected to the generator, or automatic load management must be used, according to the NEC.

Due to non-compliance with the NEC, improper standby generator size might result in an electrical inspection failure. To guarantee your family’s safety and prevent additional fees connected with a failed inspection, use a generator installer who is knowledgeable with and follows the regulations.

Can A Home Generator Power My Whole Home?

If you want to power pretty much everything in your house, your list should look something like this:

In this situation, you’d probably want at least a 35kW whole-home generator.

Conclusion – Correctly Size Your Home Generator To Match Your Unique Power Needs

Need a professional to help you find the right size generator?

We’re here to help!

• AirPlus has the engineering and technical expertise to properly size and custom package the right power solution to fit you unique applications.
• Improve the reliability of your power, increase the life span of your equipment, and lower your maintenance costs.

Contact us Today!

Thanks to the increased frequency of extreme weather events and aging grid infrastructure, electrical blackouts are occurring more often than ever. 

When a power outage strikes your home, it can cause all sorts of issues, including rotten food, frozen pipes, exposure to extreme heat and cold, and other dangerous conditions for your family.

Investing in a home backup generator is the best way to keep everyone safe — especially if the outage lasts more than a few hours. 

There are numerous types of generators available. Many operate using internal combustion engines and run on fossil fuels like gas, diesel, and propane. 

Wind and solar are increasingly popular renewable energy generators. Residential solar is more practical for most homes. 

With all the different fuel and manufacturer options, how do you know what type to choose?

And what size generator do you need to run a 2,000 ft2 house? 

Let’s dive deeper into exactly how to size and choose a backup generator for your home.

Why Is Sizing Your Generator So Important?

When people talk about generator “size,” they’re generally referring to how much AC electricity it can output and how much storage capacity it offers. 

Dimensions and weight are important considerations. But probably not as essential as understanding how many home appliances, personal devices, and systems like HVAC a generator can run simultaneously…

And for how long?

If you buy a generator that’s too “big” to meet your needs, you risk overspending — and with fossil fuel generators, wasting expensive fuel. 

Even worse is to invest in a whole home generator only to find out it doesn’t meet your family’s needs.

Should You Size Up or Down?

Sizing a generator is a balancing act. 

You may be wondering whether you should size up or down when purchasing a home backup generator. 

Both options have their pros and cons.

Sizing Up

Choosing a generator with more AC output and storage capacity than you need is the safe option — if you can afford it. 

Buying a generator that exceeds your current electricity consumption needs allows you to add more appliances and devices to the system in the future. 

However, bigger generators are more expensive and may require more maintenance. With fossil fuel generators, a larger capacity may restrict where you can install and operate the machine. Plus, high-wattage gas and diesel generators consume more fuel than smaller ones — even when the attached loads are light.

Some of the most significant drawbacks of gas and diesel generators are the noise they make when operating and the toxic fumes and greenhouse gas emissions they produce. 

The byproducts of fossil fuel generators can be deadly for your family if not used correctly and highly detrimental to the environment, no matter where they’re installed. 

Solar generators, on the other hand, are virtually silent and emit no gases or fumes. 

Sizing Down

Sizing down can be a cost-effective option that relies on your family consuming less electricity during a power outage. 

Smaller generators are more portable and easier to operate and maintain. But many small generators may be unable to power high-wattage appliances — or at least not many at once.  

This may not matter to you during a brief power outage (you can probably wait to do your laundry). But refrigerators and HVAC systems require high-wattage AC output, too, and are much harder to live without for extended periods. 

If you’re unsure whether to size up or down, try purchasing a generator with AC power output and storage capacity slightly higher than your needs. 

An additional 10-20% operating capacity gives you a buffer zone in case your consumption estimates differ from real-world scenarios. More power also allows you to add more appliances later on.

Determining What Size Generator Is Needed To Run a 2,000 Sq Ft House

Numerous factors determine what size generator you need to run a 2,000 ft2 (185 m2) home. First and foremost, the type of generator (gas, propane, or solar) will play a significant role in how big it needs to be. You’ll also need to consider your anticipated energy consumption, wattage requirements, and noise level tolerance.

Choose a Generator That Fits Your Needs

There are countless generator types and brands on the market — each with specific pros, cons, and ideal use cases. 

Many people are swapping out their noisy and wasteful gas generators for sustainable alternatives like solar, but fossil-fuel generators may still be useful in some situations.

Gas Generators

Gas generators are a popular choice due to their wide availability and various size options. They are fueled by gasoline easily sourced at any gas station. These generators range from small job-site generators to full home backup systems.

Gas generators are best suited for those who only need very occasional backup power. Gas can become very expensive, especially if you are using it as a primary source of electricity. 

Gasoline generators are inherently dangerous. Gas is highly flammable, produces toxic emissions, and pollutes the environment. Due to carbon monoxide and other harmful emissions and loud operating noise, gas generators cannot be operated indoors. They must be installed at least 20 ft from the house, and many communities may have restrictions on when (or if) they can operate.

Additionally, gasoline actually “spoils” after 3-6 months of storage. Due to safety concerns, there are typically restrictions on how much gas you can legally store on your property.

Propane Generators

Propane generators are less common than gasoline models. They operate using liquid propane (LPG), a cleaner-burning alternative to gasoline. Propane tanks are readily available and safer to store, with a longer shelf-life than cans of gas.

In general, propane generators run quieter and have a longer lifespan when compared to gas-powered models. They tend to be more expensive and lower-powered than gas generators, so they don’t enjoy quite the same popularity.

Solar Generators

Solar generators operate in an entirely different manner from gas and propane generators. Rather than use fossil fuels, solar generators use PV panels and a balance of system to convert sunlight into electricity. The power is stored in a solar battery for later or ongoing use.

Aside from wind and hydropower solutions — which are typically too large-scale for residential use — solar is the only type of generator that utilizes a clean, renewable, environmentally-friendly resource: the sun!

After the initial investment, there is no cost to operate a solar generator. You will never have to worry about sourcing and paying for fuel. And with no internal combustion engine, maintenance frequency, and costs are much lower. Best of all: solar generators are nearly silent and produce no toxic emissions.

Solar generators are ideal for home backup, but they can also save a significant sum of money on electricity bills over time. Once your solar payback period is complete, any money you save on paying the utility company is money earned!

Depending on your use case, there’s an EcoFlow portable power station that will serve you well. Whether you want to power essential home appliances during a blackout with a EcoFlow DELTA 2 or operate part or all of your home with solar on an ongoing basis, you just need to select a solution with sufficient AC output and storage capacity to meet your family’s needs. 

You can even combine the benefits of solar and fossil fuel generators by integrating an EcoFlow DELTA Pro portable power station and solar panels with the EcoFlow Dual Fuel Smart Generator. Despite being powered by fossil fuels, it is significantly quieter than traditional gas generators — especially when operated using propane.

Seamlessly combining the Smart Generator with a compatible EcoFlow DELTA series solar generator gives you even more energy security with multiple fuel and renewable power options. 

Calculating Your Household Electricity Consumption

The average American household consumes 886 kWh of electricity per month, or around 30 kWh daily. If you plan to power your entire home with a generator, you need a model that can produce at least 30 kWh daily. 

Obviously, it could be more or less than 30kWh, depending on the size of your home and your family’s unique electricity consumption needs. 

If you just want to keep the essentials running during a power outage, then your electricity consumption can be much lower.

To calculate your estimated energy consumption, follow these simple steps: 

1. Identify the wattage requirements of your appliances. Survey the starting and running wattage requirements of the appliances and devices you plan to plug into the generator. You can usually find the wattage requirements labeled on the appliance, but we’ve also compiled the starting and running watts of typical household appliances in a table below.
2. Convert volts/amps to watts. If your appliance’s power requirements are in volts or amps, you can calculate an appliance’s running watts with this equation:

Volts (V) x Amps (A) = ​​Watts (W)  

3. Count the running watts of your appliances. Add up the running watts of the appliances you plan to use — does the total exceed the running watts listed on your generator? If so, consider buying a generator with more output capacity.
4. Factor in starting watt requirements. Identify the appliance with the highest starting wattage. Add that appliance’s starting wattage to the running wattage total.
5. Calculate the sum. That final number is the total starting watts you need from your generator.  As discussed above, to avoid overloading your generator, do not exceed its starting watts rating.

Gas generators can produce energy for an unlimited amount of time as long as you have gasoline or propane on hand to refill them. For solar generators, the rate of power generation depends on the size of the attached solar array. The EcoFlow Whole Home Generator can accommodate up to eight 400W solar panels — an array of this size can produce around 12.8 kWh per day, which is more than enough to supply essential backup power to a 2,000 ft2 home. 

Another example is the expandable EcoFlow DELTA Pro Ultra, which offers a capacity starting at 6kWh and going all the way up to 90kWh, allowing you plenty of room to grow. You can add up to 42 400W Rigid Solar Panels to achieve 16.8kW of solar charging potential!

Wattage Requirements

Do you need to power a whole house every day? Or will you be using your generator for emergencies only? 

Even if you have the battery capacity or fuel to supply power to your home, the generator must have high-enough starting and running wattage AC output to accommodate the loads it will receive. 

Many people aren’t aware that high-wattage appliances require significantly more AC output to start than they need to operate. Appliances like refrigerators, washer/dryers, and HVAC systems are prime examples.

Keep in mind, gas generators can usually offer only a few hundred watts more of starting power in a short burst to turn on appliances. The extra electricity required to get a device up and running is referred to as starting watts or surge power. The wattage necessary to keep a device operating once it’s turned on is called the running watts — and this is the number that appears on manufacturer’s product labels.

Many people are unaware of the difference between starting watts and running watts. That’s understandable. When you plug a high-wattage appliance into an AC wall outlet in your home, it’s more than capable of delivering sufficient starting and running watts. 

However, this is not the case with generators — especially those powered by fossil fuels.

Thanks to proprietary X-Boost technology, EcoFlow’s portable power stations and solar generators can produce up to double their operating AC output. 

For instance, the EcoFlow DELTA 2 Max has an operating AC output of 2,400 running watts but can deliver a surge of 4,800 running watts to power up high-wattage appliances. It can also operate up to 3400W of appliances simultaneously by intelligently minimizing the power requirements of appliances while they’re running. Many appliances do not require their full-rated running wattage to continue operating.   

Understanding the difference between starting and running watts is crucial when determining which generator will meet your energy consumption needs.

To help you estimate your wattage requirements, here are various household appliances’ average starting and running watts. Remember, these numbers will differ between manufacturers and models. Always check the product label, manual, or manufacturers website for the exact starting and running watts required by your appliances: 

Noise Level

Gas generators are notoriously noisy. RV parks have limits on the hours you can operate a gas generator, and some campgrounds have outright bans.

Your locality or community associations may also restrict the usage of gas generators to certain hours — or forbid them altogether.

The average gas generator produces 80-100 decibels (dB) of noise — comparable to the “inside of an airplane or an approaching subway train.”

If noise level is a concern, solar generators are the clear choice. They are practically silent — some models might exhibit a quiet hum, which is just the inverter converting the DC power produced by your solar panels into AC power for your devices. Operating noise from an EcoFlow solar generator or portable power station should never exceed 50 dB.

Indoor vs. Outdoor

Do you need to run the generator indoors, or is outdoor operation okay? Solar generators are the only type that is safe to operate indoors. Propane and gas generators both use liquid fuel, which is flammable. They also produce deadly emissions when they run, making outdoor installation a necessity.

Frequently Asked Questions

Selecting a generator with a capacity of 15,000 watts is recommended to adequately power a 2,000 sq ft house, including essential appliances and systems. A generator this size ensures reliable backup for most homes’ critical needs.

How Much Is a Generator for a 2000 Sq Ft House?

The EcoFlow DELTA 2 Solar Generator currently retails for USD $1,299 with a 220W Bifacial Portable Solar Panel included and has 1024Wh of storage capacity and 1800W of AC output (Surge 200W). It can be used for essential backup power for a 2000 ft2 house. The top-of-the-line EcoFlow DELTA Pro Solar Generator has over double the power output (3.6 kW running watts/7.2 kW starting watts). It’s available in various configurations, as it offers 1600W of solar input (up to 4 x 400W solar panels). The retail price of the EcoFlow DELTA Pro Solar Generator with one 400W portable solar panel is currently just over USD $3,599. The EcoFlow DELTA Pro is expandable up to 7200W of AC output (14,400W surge power with X-Boost) and 25kWh of storage. It is the heart of EcoFlow’s whole home generator solution.

Final Thoughts

Having the right generator on hand can give you and your family peace of mind and energy security during your next power outage. 

As long as you plan ahead and purchase the right size generator, you’ll be able to keep your essential appliances and devices powered up during the next blackout. 

EcoFlow offers a complete line of solar generators to fit any need. The Whole Home Generator system can keep an entire house running during a power outage. At the same time, their smaller solar generators are perfect for short blackouts, RVs, job sites, and even backpacking! Check out EcoFlow’s solar generators today.