When it comes time to buy a portable generator, taking the time to figure out just what exactly you need as far as size is very important. The first step in doing that is to first really look at what you are using the machine for.
The most common uses for a portable generator would be for power back up in the event of a power outage, recreational use and use on the job site. Each one of these uses has very different power demands and would possibly require different machines.
For a portable generator you are using for power back up, the most important part of figuring out how much of a generator you need is to really look at what your very basic needs are in the event of an emergency power outage. This will vary from household to household. For example, if you are in an area where power can be knocked out long term and you need to be able to power up your larger appliances like a refrigerator, maintain heat or cooling depending on the climate, support an alarm system or other household needs you will need a much larger generator than someone who just wants the very basics.
The biggest part of deciding which size to purchase is to really look at what you will need to power, and then going from there. If you have never actually had to depend on a generator, it might be useful to use an online calculator to guide you through the sizing process.
These tools generally give you a checklist made up of all sorts of household features and machines you may need to power. This is helpful to remind you of things you may not consider on your own if this is the first time you have bought a generator.
For the very basic needs that can be hooked up with a simple extensions cord, a medium sized generator will do. The next size up from there is a large generator that would connect either via cords or switches so they could handle several appliances but not overall household systems like a security system. An extra-large generator would support the full household systems via the use of switches.
Recreational uses for portable generators would usually have a different set of requirements than one you would buy for home supports. While a home based machine can be larger if it is needed, space is often a premium for recreational uses like an RV and supporting toys hauled in an enclosed trailer. When traveling with a generator, you need to balance the amount of power you need with the space you can dedicate to hauling the unit.
Buying a work site portable generator usually would focus less on the size of the unit and more on the utility. A unit used for work would have very specific demands including operating certain machinery or tools that will determine how powerful the generator needs to be. Using industrial sized tools for example may require a much larger generator than you would ever consider hauling along for recreation. This bigger unit may also need a heavy duty electrical system with switches to support the most powerful of tools.
In order to decide on the size of portable generator to purchase, you need to figure out what your ultimate use of the machine is going to be and what type of demands you will put of the machine. The best unit for home emergency supports may not be the best unit for recreational use or to take to work. Being realistic about just what type of supports you need from the generator will help to make sure you get the best unit for your needs.