What Size Generator Do I Need How Big of a Generator Do I Need

What Size Generator do I Need?

Posted in: Diesel Generators Engine & Drivetrain Power Outages

What Size Generator Do I Need?

When your home or business experiences a blackout, it can create a serious safety issue. According to the U.S. Energy Information Administration, the average American experiences around 7 hours of blackouts every year, almost twice as many as a decade ago. Buying a generator is a great way to prepare for these increasing outages. If you are planning to purchase a generator, you have probably wondered, “How big of a generator do I need?” To answer that question, you must first have an idea of how much electricity your home or business requires, which will help you choose the proper generator size.

Ideally, you will hire a certified electrician to visit your home or business and determine your generator wattage requirements. Every appliance or electronic device you use contributes to your home or business’ total power consumption. By figuring out how much power each piece of equipment uses, you can get a more accurate picture of your needs.

If you need to calculate your power requirement on your own, this article will help you. Let’s take a look at how to determine what generator size you need and how Americas Generators can help you find the right mobile generators for your needs.

How to Determine What Size Generator I Need?

Generator power output is measured in watts in the US. Most devices indicate how many watts they use on the device itself or in the user’s manual. However, there are two different types of power output figures you need to be aware of when buying a generator, and both are essential to determining the correct generator size you need:

  • Continuous Power Rating, or Running Watts – The continuous power rating is the amount of power a generator can deliver consistently while it is running.
  • Maximum or Surge Power, Also Known as Starting Watts – Starting watts is an additional boost of power the generator is able to deliver in short bursts to start your appliances.

For example, most refrigerators use 1,200 watts of power when they are starting up, but only draw about 200 watts when they are running. You need to make sure your generator is strong enough to run all of your essential appliances and also has the surge power to start them up.

Calculating Electrical Consumption

If you are asking, “How many watts do I need for a generator?”, you can calculate your home or business electrical needs by adding up the consumption of your individual appliances or devices. 

Most devices will list the wattage somewhere on the device or in the documents that come with the appliance or device. If the device or the appliance does not indicate its wattage, there are other options for determining it. You can buy a measuring device, such as the Kill A Watt. Simply plug the device into the wattage-measuring tool and watch for the reading.

For purposes of buying a backup generator, compute only the devices that you cannot do without. During power outages, you can disconnect appliances or devices that aren’t absolutely necessary for maintaining the health, comfort and security of your family and employees.

By adding up the wattage consumption of the essential machines, you will come up with the total number of watts you need for your generator. Essential items likely include your:

  • Refrigerator
  • Stove
  • Lighting
  • Medical equipment
  • Microwave
  • Furnace
  • Water heater
  • Air conditioning
  • Laundry equipment

 If you are buying a generator for a business, you may need to consider other items, like computers and other necessary equipment.

How Is Generator Power Measured?

The United States measures generator power with kilowatts (kW).  The rest of the world uses kilovolt-ampere (kVA) when they talk about generating power. You can calculate the kW consumption of your house by converting the total watts of usage you have calculated. There are 1,000 watts in a kW, so divide your wattage total by 1,000 to arrive at your home’s kW consumption. As an example, if your devices and appliances consume a total of 35,000 watts, your consumption is 35 kW.

The kW rating of a generator is based on the horsepower of the engine. To determine kilowatts, multiply the horsepower rating of the generator’s engine by .746.  For example, a 500-horsepower generator engine has a kW rating of 373. If your house consumption is 350 kW of electricity, you will need at least a 500-horsepower generator with a kW rating of 373.

If you are unsure or feel you might be missing some equipment, it is always best to consult with a certified electrician who can provide a more accurate picture of your power needs.

What Is the Hz of a Generator?

Another factor to consider when buying a generator is the Hz (Hertz). The Hertz frequency represents the number of cycles per second that an electrical system operates at. In most regions, including the United States, the standard frequency is 60 Hz. However, some countries and applications may require a different frequency, such as 50 Hz.

Why does the Hz matter? Well, it directly affects the performance and compatibility of your electrical equipment. Many sensitive devices, such as computers, medical equipment, and industrial machinery, rely on a stable and accurate power supply with the correct Hertz frequency to function optimally. Deviations from the required frequency can lead to malfunctions, reduced efficiency, or even equipment damage.

When selecting a generator and choosing the right generator size, it’s essential to match the frequency of the generator to the frequency required by your equipment. Running your sensitive devices on a generator with the wrong frequency can have serious consequences. This is why Americas Generators offers a range of generators with different frequencies to accommodate various applications and ensure seamless compatibility.

Generator Size Considerations to Keep in Mind

When determining what size generator you need, there are a few additional considerations to keep in mind:

  • Fuel type: Decide on the fuel type that suits your preference and availability, such as gasoline, diesel, propane, or natural gas. Different generators run on different fuels, and each has its own benefits and limitations.
  • Runtime: Assess the expected duration of power outages in your area. Choose a generator with a fuel tank capacity and fuel efficiency that can provide sufficient runtime without frequent refueling.
  • Noise level: Consider the noise level of the generator, especially if you plan to use it in residential areas or out in the field. Look for generators with lower decibel ratings for quieter operation.
  • Safety features: Ensure the generator has important safety features like overload protection, low-oil shutdown, and GFCI outlets for added protection against electrical hazards.
  • International requirements: Different areas may have different regulations and standards regarding energy usage or safety, so be aware of any issues that may arrive. We offer a range of export generators that are suitable for use in most areas of the world.

Trust Americas Generators for Your Generator Needs

If you have questions about what generator size you need for your home or business, Americas Generators has you covered. We offer a wide range of portable generator sizes so you can find one that best meets your needs. Whether you are looking for a standard diesel generators or more efficient Tier 4 generators, we are here to help you. Contact our experts today and discover the difference the right generators can make.

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