Production and Exploration
There are 15 fields and wells that produce gas in New Zealand, all in the Taranaki region. Production is dominated by the Pohokura field and the Maui field. Shell and Todd Energy-owned subsidiaries control a large portion of New Zealand production.
The large Maui gas field was discovered in 1969, and initially it offered more gas than New Zealand needed for domestic use. In the early 1980s, the government sponsored a number of large construction projects to promote economic development in the face of sharply rising world oil prices. Some of these ‘Think Big’ projects were dependent on Maui gas, including an ammonia-urea plant, the Motunui synthetic petrol plant, and the Waitara methanol plant. In addition, other types of gas demand, particularly power generation, continued to grow throughout the 1990s and into this decade. The Maui discovery also triggered a substantial expansion of the high pressure gas transmission system to provide gas to most large cities and towns in the North Island.
A series of market reforms were implemented in the 1990s, which led to the gas industry moving to market-based pricing and the government reducing its previously heavy commercial involvement in the market.
In 2013, net gas production totaled 180 PJ. This information is sourced from MBIE's 2014 Energy in New Zealand publication.
Gross Gas Production by Field for 2013
All major basins in New Zealand exhibit hydrocarbon seeps, but there has been little historic exploration outside the Taranaki basin. Even the Taranaki basin is considered lightly explored on an international scale. The potential for major gas and oils finds in the wider New Zealand Exclusive Economic Zone (the area of sea and seabed that extends 12 to 200 nautical miles offshore) is considered high.
The government has implemented a number of measures through its Petroleum Action Plan to encourage gas exploration. These incentives, which range from tax breaks to government-funded seismic surveys, coupled with the decline in the Maui field, have resulted in a substantial increase in exploration and development activity in recent years. Wells were drilled in the years 288 to 2012 (includsive). Drilling also included coal seam gas plays, an 'unconventional' gas source that has considerably expanded gas reserves in other countries - notably Australia and the United States.
New Zealand's gas reserves have remained relatively stable over the years, as production is replaced by new discoveries or production enhancement initiatives on existing fields. In that period, the reserves/gross production ration has been in a band of between 10 and 12 years. As at 2014, remaining gas reserves were approximately 2560PJ. Reserves by field are:
The Contact Energy Ahuroa gas storage facility supports a 200 MW gas peaking electricity generation plant commissioned at Stratford in 2011. Ahuroa is New Zealand's first large-scale gas storage facility and has the potential to improve the flexibility of New Zealand's gas supply.