Gas Generators
There are two main components in every electric generator, a motor that burns fuel to supply power and the output otherwise known as a head that converts the current into electricity.
A gas type machine produces a lot of heat as it runs. They are typically cooled by a built in air system. These systems make them more light as well as easier to maintain.
However, gas generators have a down side. They are known to run quite loud and generally hotter than other generators that are cooled by liquid.
Most run at 3600 RPM (Revolutions per Minute). The benefit is that this makes them smaller and lighter than other varieties such as an 1800 RPM model. They are good travel generators for those who drive RV's or need power at campsites.
Gasoline powered generators do produce a lot of power for their relatively small size. The negative side is that they don't run for long periods of time. These systems aren't equipped to run for days and days continuously. They must be refueled more often, so if there's also a gas shortage or an inability to drive to retrieve gas, this type of generator would be less desirable for long term.
It's more common that natural gas or propane systems are used as fuel for stand-by generators that may be used when it's known that power will be out for weeks or months.
If you know that you will need a generator to supply power for a short term period a gas powered system would be fine. However, it's always best to talk with a sales representative if you have any questions or apprehension about what system to purchase. They can help ensure that whatever you intend to purchase meets your needs when it has to.