What’s the Difference Between Starting Watts and Running Watts?

If you’re shopping for new appliances, you will inevitably run into two ratings that may appear similar at first glance: starting watts and running watts. The two terms are not interchangeable. Each provides essential specifications for how much power an appliance will consume from your generator or electrical system.

When purchasing an appliance, it’s easy to overlook the fact that many large appliances have a high starting watt rating. While this probably doesn’t matter if you’re plugging a device into a wall outlet, it can cause significant problems when attempting to use it with a generator. 

If an electronic device’s starting watt requirements exceed the generator’s AC output capacity, you won’t be able to turn it on. 

Let’s learn more about the differences between running and starting watts and how these figures affect an appliance’s compatibility with generators. 

How to Calculate Total Running and Starting Watts Requirements

Running watts (also known as rated watts) is the amount of power that an appliance draws continuously. Starting watts (peak or surge wattage) refers to the power a generator must provide momentarily to turn on an appliance. 

Typically, this power surge is only required for a few seconds before an appliance starts operating at its running watts rating.

Running and starting watts requirements differ for every appliance. Many devices require no surge power at all to turn on. Some need over double their operating wattage to get up and running. 

To accurately determine the AC output of the generator you need, you must calculate the total starting and running watts that it can provide simultaneously. 

Follow these simple steps to estimate your starting and running wattage needs.

  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 labelled on the appliance, but we’ve also compiled the starting and running watts of typical household appliances in the 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)  

  1. 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.
  2. Factor in starting watt requirements. Identify the appliance with the highest starting wattage. Add that appliance’s starting wattage to the running wattage total.
  3. 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.

Starting and Running Watts of Typical Household Appliances 

ApplianceRated (Running) WattsStarting Watts
Washing Machine12002300
Light Bulb60-750
Coffee Maker10000
Clothing Iron15000
Toaster Oven12000
Curling Iron15000
Space Heater20000
20” Box Fan200350

Gas Generators vs Solar Generators: What is Best for Starting Wattage?

Gas generators typically have a starting wattage rating that is only 10–20% higher than the running wattage. Yet, high-powered gas generators are relatively cheap, and the starting wattage is only limited by the amount of fuel that can be pumped through the engine at one time. So, if you buy a large-enough gas generator, you should be able to power most home appliances. 

On the other hand, the EcoFlow line of portable power stations and solar generators can provide up to 2x their rated running wattage to start appliances using proprietary X-Boost technology. Even small, low-cost solar generators — like EcoFlow’s RIVER 2 Series — can power up to 80% of high-wattage home appliances. 

So, if both types of generators can provide high starting wattages, how do you choose between the two? 

Well, have you heard the loud noises that a gas generator produces? Or inhaled the toxic fumes that the engines put off? 

Solar generators don’t have these issues. They are clean, quiet, and powered by renewable energy. All you need is at least one solar panel to harness the sun’s energy, although they can also be charged using a wall outlet and other charging methods to be used as a portable battery system. 

What is X-Boost?

X-Boost is a proprietary feature found only in EcoFlow portable power stations and solar generators that provide a short burst of starting watts (also known as surge power) up to double its rated running watts. 

When traditional generators attempt to operate high-powered appliances, they experience issues like overloading and overheating — and often simply fail to turn a device on. 

With X-Boost, you can safely start up appliances that are at least twice the operating AC output on your solar generator.

Technically X-Boost doesn’t increase the rated AC output of a portable power station. 

Instead, the proprietary technology utilises innovative power management to reduce the voltage and current of your appliances, allowing you to do more with a lower-power generator. 

X-Boost provides a temporary surge in starting watts to get high-powered appliances running.

The highest-powered portable power station — the DELTA Pro — is rated for 3600 running watts. But, utilising X-Boost technology, this is increased to a whopping 4500W. 

Plus, when paired with another DELTA Pro unit, the AC operating output increases to 7200W.

X-Boost technology is also packed into EcoFlow’s smaller RIVER 2 series of portable power stations. The RIVER 2 Pro is rated for a modest 800 running watts. But with X-Boost enabled, this is doubled to 1600W, allowing the user to power most home appliances.

X-Boost is a proprietary EcoFlow technology unavailable in other solar generators and portable power stations. 

Frequently Asked Questions

What Does Starting Watts Mean on a Generator?

Starting watts — also referred to as peak watts or surge power — is a specification for the extra power that an appliance will draw upon startup. The term is also used to denote the amount of startup power that a generator can provide. After an initial surge, the appliance and generator revert to running watts.

Final Thoughts

Be careful to consider both the running watts and the starting watts for appliances in your home when attempting to power them with a generator. 

While a refrigerator may only draw 700 running watts, it may need up to a massive 2200 watts when starting up. Appliances using motors typically have the most significant discrepancy between starting and running watts. 

Ensure your generator or other power source can handle the surge power the appliances you want to run off-grid require to start up.

EcoFlow’s solar generators offer high running wattage and surge wattage AC output. For example, DELTA Pro is a high-capacity, high-output solar generator that allows you to power all of your home’s appliances and HVAC systems using the power of the sun.

EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.


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