The Van-De-Graaff generator is used by machines which require an electrical potential difference to function, an example of this is the electrolyzer and the toroid magnet. The Van De Graaff generator's power output is dependant on the power supplied to it and has no lower or upper limit suggested by testing. The speed of electrical power transfer is directly proportional to the rate at which its electrical bolts hit the machine it is powering.
This machine should be used with caution as it will also transfer its electrical power to the player causing damage if they are in range. Damage can be avoided by automating any process involving machines requiring the generator to avoid the need for proximity during its operation.