Some do some don't.
There is no law requiring generators and if one was needed the school wouldn't be in session. Classes would be cancelled. So, there are no generators in schools.
Some do.....
There are no reports of a vandergraff generators being a danger to schools or any other structure. Ironically there is also a popular European rock band with the same name.
Very few - since our electricity grid is the most stable it's ever been. It's not common practice to build UK schools with generators. Private schools have different rules - but state schools rarely have generators.
Northern Tools sell a large variety of generators. They offer generators for your RV, Commercial Standby Generators, PTO Generators, Residental Stanby Generators and Invertor Generators.
Propane generators are portable. These can be used in RVs. There are also diesel generators and emergecy generators. All of these generators are portable.
The two main types of generators are portable and standby. Portable generators include recreational, residential, and industrial generators. Standby generators include welder generators and vehicle mounted generators.
Emergency generators can be found anywhere, it just depends what kind you want. If you want a portable generator, you can often find them for sale on the web, as well as at hardware/tool stores. Bigger emergency generators that are used for homes/schools, can SOMETIMES be found at hardware stores, but often you would have to buy from a big manufacturer, which you can find and research on the web.
There are a number of alternative names that are commonly used for signal generators. They are often referred to as pitch generators, function generators, and arbitrary waveform generators, for example.
Hydro electric generators wind powered generators geothermal generators
You can read reviews of LP generators at the sites of stores that sell the generators, such as Amazon, Northern Tool, and Home Depot. The website Propane Generators Reviews is also a good source for reviews of LP generators.
Yes, there are bio-fuel compatible portable generators. For example, Kentec Generators create these, which are very Earth-friendly. Powered Generators also supply bio-fuel compatible portable generators.