Powerco chief executive Steven Boulton said that the oversubscribed US placement does not increase Powerco's existing level of debt but will replace some of the company's existing senior bank funding facilities, which were raised for the acquisition of the UnitedNetworks assets last year.

The company doubled in size late last year with the acquisition of electricity and gas network assets from UnitedNetworks Limited. Boulton said the company is also looking to refinance some of the remaining acquisition funding raised last year with a further domestic issue of medium term notes in New Zealand.