Approved costs incurred by Transpower in relation to an approved economic or reliability investment, or interim grid expenditure approved under rule 16, are recoverable by Transpower from designated transmission customers on the basis of the transmission pricing methodology.

To date, the Commission has made final decisions on two investment proposals submitted by Transpower (the North Island Grid Upgrade Proposal and the Otahuhu Substation Diversity Proposal). The Commission is also currently processing a number of other investment proposals (North Auckland and Northland Proposals, the West Coast Upgrade and the HVDC proposal).

In addition to these major projects, a number of transitional investments have been approved using the transitional provisions in rule 16 of section III of part F of the Rules. Since then, Transpower has sought amendments to the approved project costs for four of the approved projects.

The Commission decided on requests for amendment to the following and is currently processing a request for amendment in relation to TTU27.:

  • TTU 28 - Bussing of Christchurch-Twizel Line A at Ashburton
  • TTU 27 - Duplexing of the Islington-Livingstone 200kv circuit
  • GDP 6 - Replacement of 220/110kV interconnecting transformers at Kikiwa
  • GDP 8 - Replacement of 220/110kV interconnecting transformers at Stoke

The document below provides the list of projects submitted by Transpower and the Commission decisions (as at 14 January 2010).