The standard reply is usually along the lines of;
///******** ******* do endeavour to provide a continuous supply of electricity but as circumstances can occur which are beyond our control, we are unable to guarantee an interruption free supply, as stipulated in your supply connection agreement. We therefore advise our customers to insure against any losses, which may occur as a result, as consequential and economic losses are not recoverable under current law (The Electricity Supply Act 1989 & Associated Regulations. We can only suggest that you claim via your own insurers.///