Portable generator calculator: It can be very confusing trying to understand what size of generator you need for you project / use. Multiple considerations can come into play, but we will try and make it easy for you to narrow down your choice for your portable generator with these guidelines to calculate. First, remember this guideline: the average sized home requires 5,000 to 7,000 watts to run and power essential equipment / items for the house. As we are focused more of a portable generator calculator, we tried to pick items that maybe most likely you would need to run.
Portable Generator Calculator | What Size is Needed?
To dive in deeper, you can make it easier to focus on two considerations:
- Continuous Power (which is also referred to as ‘running watts’) is the wattage you will require to operate appliances under normal load.
- Extra Peak Power (this is what we call ‘startup watts’) this is the extra wattage you will require for appliances at the beginning (the startup phase) or when they are running at their highest levels of power consumption. You must factor this in, or you won’t even get things started.
When you consider the idea of power surge, it helps you get your head around what items are harder to run vs easy. Cell phone charging is easy, washing machine is harder on your generator. A radio is very easy compared to a circular saw. A food processor has a surge, a crockpot does not. You get the idea.
Read the chart below to see our portable generator calculator. Create your list of what you need to run (at the same time) and add up your combined power needs to understand what size of generator you need.
Items with no surge to worry about (number in brackets is the running watts required)
Cell Phone Battery Charger (10 running watts, no surge)
Laptop Computer (75 watts)
Cell Phones = iPhone, Blackberry, or ipod (80 watts)
Small TV (13”) (100 watts)
AM/FM Radio / CD Player (100 watts)
20” Fan (200 watts)
Normal Home Video Game system (200 watts)
Crockpot (250 watts)
Computer Desktop (300 watts)
TV with DVD (300 watts)
TV – Mid size 27” (500 watts)
Single Element Hot Plate (750)
Coffee Maker (800)
Toaster – regular size – two slots (850)
Deep Fryer (1,200)
Space heater (1,800)
Electric range (2,100)
Electric Water Heater (4,000)
With Surge (the first number in the bracket is still the running watts, but you need to add in the second number, which is the surge number)
Refrigerator – small size (350 and 500 surge)
Food Processor/Blender (350 and 500)
Small Power Tools; Electric Drill (440 and 600)
Refrigerator / Freezer (600 and 2,200)
Microwave Oven 750W (750 and 800)
Sump Pump (800 and 1,400)
RV Low Profile Air Conditioner, 13,500 BTU – Heating (1,600 and 2,300)
Circular Saw (1,500 and 3,000)
Remember, combine running watts and surge watts together for everything you plan to run at one time. Good luck, enjoy your generator and the freedom / flexibility portable power can give you!
Here is a video from Consumer Reports on portable generators:
For other reference, here are free generator calculators for your consideration, I think they are appropriate for your portable generator calculator exercise:
Honda Wattage Calculator from the Honda Power Equipment site:
Generac Home Backup Portable Generator Calculator
Briggs and Stratton Portable Generator Calculator and Buying Guide
Other Generator articles to explore: