What are the difference between high voltage and low voltage?

Hi, The main difference is Fuel consumption. High current genertors always consumes much fuel because the load on the engine will be high. The high voltage low current generators doesn't need much fuel to run. You can understand this by comparing 1 kva and 5 kva single phase generators. For both generators voltage will be same (230v) But output current differs. So the fuel consumption also differs. But you get a high current source. Low voltage high current generators can be used for welding kind of stuffs which needs high current to do the job. If you have step down transformer then you can save the fuel.