What is the Commission's role with regard electricity transmission?

The government has charged the Commission with addressing transmission decisions that include: approving a grid-pricing methodology for national grid company Transpower; assessing plans for Transpower to upgrade the grid in critical places; approving investment where it meets the requirements; and overseeing the contractual relationships between Transpower and the companies that receive services from the national grid.

Who decides that a new transmission line is needed, or not needed?

It is Transpower's job to plan the development of the transmission grid. When Transpower believes an upgrade is required, it proposes an investment in a grid upgrade plan which it submits to the Commission for approval.

It is the Commission's job to decide whether or not to approve the investment, taking into account the costs and benefits of all the options and alternatives.

Transpower needs to go through Resource Management Act processes.

More

More about transmission