Brown coal companies will be hit by a dramatic three-fold tax increase, with the Andrews Government insisting the impact on power bills will be "negligible in the extreme".

The tripling of Victoria's brown coal royalty rate - to be detailed in the state budget on Wednesday - will kick in on January 1, netting an extra $252 million over four years to help pay for the Government's infrastructure, health and education agenda.

State royalties from brown coal mines set to triple

Treasurer Tim Pallas on Friday evening said the increase would bring Victoria's mining royalty rates into line with NSW, Queensland, and Western Australia, warning power companies to think very carefully before attempting to pass on the added pain to consumers.

"The royalty is paid ... for the use and extraction the resource the mine operator manages on behalf of the community, and this increase will basically ensure Victorians get their fair share," Mr Pallas told Fairfax Media.