In this issue:

• Spot Market Commentary
• Spot Market Prices
• Hydro Storage

Spot Market Commentary

Spot market prices for the month of May averaged $271.72 at Haywards.

Overall New Zealand storage fell 8% to 36% of maximum capacities. May produced this highest-ever monthly spot prices, on the back of receding hydro lake levels and constraints in both the DC-link and in thermal generation in the North Island. Whilst hydro inflows remain low, high spot prices are forecast to continue, and all electricity users are being urged to limit consumption wherever possible.  Major consumers have already reduced production, such as the Aluminium Smelter at Tiwai Point. Now large and medium-sized commercial customers are being urged to follow suit.

Visit www.winterpower.co.nz for more information.

Spot Market Prices

The Spot Market averaged $271.72 at Haywards for May 2008, a major increase from $118.89 for April 2008. Half-hour spot prices at Haywards were much more volatile this month, with a high of $599.50 for period 28 on 29th of May, and a low of $34.28 for period 8 on the 14th of May.

Spot Price Statistics

Average Daily Prices

Average Half Hour Prices

Hydro Storage

Inflows for May for New Zealand were above average for only 3 days of the month. Overall South Island storage fell 13% to 34% of maximum capacity, whilst North Island storage rose from 33% to 37%.

The overall NZ level fell 8% to 36% of maximum capacity.

National Storage

The NZ storage level currently sits well above the EC Operational Minzone, as the following diagram illustrates:

Disclaimer: The information contained in this document is based on information that has been provided to Mighty River Power Limited or its related companies by third parties and is intended for general reference only. Whilst every effort has been made to ensure the accuracy and completeness of the information contained in this document, this document is provided on the basis that neither Mighty River Power Limited nor any of its related companies make any representation or warranty as to the accuracy or completeness of the information contained in this document. Neither Mighty River Power Limited nor any of its related companies shall be liable for any losses, damages, costs or expenses suffered or incurred by any person who elects to rely on the information contained in this document.