Todd Energy

Production sites

Click on the production site names below for more information on each site.

McKee is the largest producing onshore oil field in New Zealand, although as the field matures focus is gradually shifting from oil production to development of the overlying gas cap.

The field is 100% owned and operated by Todd Energy.

Field location

The field is located in Taranaki, 20 km SE of New Plymouth, with the McKee Production Station some 12 km inland from the Methanex Motunui complex. Forty wells have been drilled from 13 well sites scattered over the surrounding farmlands and oil, gas and water flow via an extensive in-field pipe network to the McKee-Mangahewa production station for processing.

Field history

The McKee oil field was discovered in 1980 by state-owned Petrocorp Exploration Ltd. Over the next four years a number of accumulations in adjoining fault blocks were discovered, Pouri, Pukemai, Tuhua and ToeToe, although it quickly became apparent that these compartments formed part of the overall McKee field.

The geologically complex McKee structure is a major thrust fault, with a north-east direction. The hydrocarbon accumulation occupies a steep south-easterly dipping (up to 60^o) sandstone reservoir sequence truncated against the fault at a depth of 2000-2400m below sea level. The field is cut by a number of lesser reverse and normal faults, which may consist of multiple faults or fault zones.

The oil was located in a thick oil rim, located on the flank of the structure, with a gas cap overlying this rim in the crestal part of the field. Due to compartmentalisation, the original fluid contacts varied from block to block.

Production from the field commenced in early 1984.

With an active drilling programme oil production was initially maintained around 10,000 stb/d, but in the early ‘90s oil production declined steadily, while at the same time gas and water production increased.

In 1988 Petrocorp Exploration was sold to Fletcher Challenge Energy, which was acquired by Shell in 2001. To achieve Commerce Commission clearance for their purchase of FCE, Shell sold the McKee asset (PML 38086), and the nearby Mangahewa asset (PMP 38150), to Todd Taranaki Ltd.

Since acquiring these assets, the steep decline of oil production has been slowed and the reserves have been reassessed. In recognition of the higher gas reserves, Todd increased the gas processing capacity by 40%, while at the same time it commenced gas reinjection in order to enhance the oil production and ultimate recovery.

Field facilities

The McKee facilities currently consist of 40 wells linked through product gathering lines to the McKee Production Station. At the production station the well fluids are processed (separated and stabilised) into a gas stream, an oil stream and water.

The treated gas is compressed, and injected into the gas export lines. The stabilised oil is trucked to export storage facilities at Port Taranaki in New Plymouth. Treated produced water is injected in a water disposal well.

In late 2011 a LPG recovery plant (27,000 tonne/annum) was commissioned, which can run on imported Pohokura gas and/or McKee-Mangahewa gas.

Field statistics

Mangahewa is a gas-condensate field adjacent to the McKee oil field in North Taranaki. The field is linked to the McKee Production Station, which was extended with high pressure gas processing facilities to accommodate the produced fluids from Mangahewa. 

The field is 100% owned and operated by Todd Energy.

Field location

The field is located in Taranaki, 18 km SE of New Plymouth, next to the McKee field some 10 km inland from the Methanex Motunui complex. To date the field has been developed with eight production wells, and multi-phase flowlines to the McKee-Mangahewa Production Station where the wellstream is processed.

Field history

The Mangahewa Structure was recognised as a prospect in the early days of exploration in New Zealand, with the exploration well Mangahewa-01 drilled in 1961 by the Shell-BP-Todd Joint Venture. The well found traces of gas in the Kapuni Group (ca. 3500-3600m below sea level), and on testing produced water with a small, sub-economic amount of gas (1-2 mmscf/d). The well was subsequently plugged and abandoned.

Further exploration occurred in the mid 1990s, with Fletcher Challenge Energy drilling the Mangahewa-02 gas discovery well (1996/97) in this low relief anticline situated to the west of the McKee overthrust. This was followed by short and long term production testing of this well (1997), acquisition of 3D seismic (1997), and testing of the northern flank of the Mangahewa structure with Ohanga-2 well (1998).

Permanent production from the field commenced in September 2001.

In 2001 Fletcher Challenge Energy was sold to Shell, and, to achieve Commerce Commission clearance for their purchase of FCE, Shell onsold the Mangahewa asset (PMP 38150), and the nearby McKee asset (PML 38086), to Todd Taranaki Ltd.

Since acquiring these assets, Todd Energy has reassessed the reserves and appraisal/development opportunities within the Kapuni formation based on well performance and subsurface studies. This has resulted in the drilling of appraisal wells Mangahewa-03 (2007), Mangahewa-04 (2009), and Mangahewa-06 (2009).

The results of those appraisal wells provided the foundation for the Mangahewa Expansion Project, which was formally announced in January 2012 in conjunction with a 10 year gas sales agreement between Todd and Methanex. This expansion project, which is expected to cost in excess of $750 million, and which targets to mature 450 PJ of contingent gas resources into 2P gas reserves, consists of:

• Approximately 25 appraisal and development wells
• A gas processing facility expansion of 25 PJ/a
• Installation of an additional gas export pipeline, and
• Additional gathering lines and wellsite facilities.

The fifth well of this programme was spudded on 29 October 2012.

Field facilities

The Mangahewa facilities consist of eight wells with associated wellsite facilities, connected via multiple gathering lines to the McKee-Mangahewa Production Station. Fluids are treated in a single high pressure gas train. The McKee facilities are used for the provision of utilities and for treating condensate, water and LTS liquids.

Field statistics

Kapuni is the oldest producing gas-condensate field in New Zealand, and this mature onshore field is surpassed in original size only by the offshore Maui field.

The field is held as a 50:50 Joint Venture between Shell (Petroleum Mining) Co. Ltd and Todd Petroleum Mining Company Ltd and is operated by Shell Todd Oil Services Ltd, also owned equally by Shell and Todd.

Field location

The Kapuni field is located in the shadow of Mount Taranaki, near the small Kaponga township, some 65 km south of New Plymouth, and 10 km west of Eltham.

Eighteen Kapuni field wells are distributed around the surrounding farmland on nine wellsites, and gas, condensate and water production are fed by underground pipelines from these wellsites to the Kapuni Production Station for processing.

Field history

The Kapuni gas-condensate field was discovered (Kapuni-1) in 1959 by a Joint Venture consisting of Shell (37.5%), BP (37.5%) and Todd (25%). Field appraisal took place in 1962-1963 with the drilling of three additional wells Kapuni-2 to -4.

The gas is located in the Mangahewa formation, some 3400-3800m below surface, in a sequence of sand, shale, coal and siltstone layers of variable quality, which form a large anticlinal structure sealed by the Otaraoa marine mudstone. The main producing intervals are located in the K1A and K3 intervals, but several sub-units with limited vertical connectivity are recognised within these main units. Field connectivity is also influenced by several in-field faults - especially the NW- E running Kaponga fault zone.

Due to the high carbon dioxide (CO₂) concentration of the gas (44%), which requires special processing, and the lack of a natural gas infrastructure at the time, it took until 1967 before a gas market was established with the Crown and a gas purchase contract negotiated and executed. The field subsequently came onstream in 1970.

The Kapuni discovery was a landmark event that had commercial significance for New Zealand. It launched a new era that saw consumers taking advantage of gas as an efficient and low-cost energy source for industrial and domestic use. Kapuni's success also led to the development of Taranaki's energy infrastructure.

Production from Kapuni peaked in the mid-late 1970s at ca. 70 PJ/annum as part of the pre-Maui development of the gas market (in particular Kapuni gas fed the New Plymouth Power Station for electricity generation). Once Maui came onstream in 1979, and Kapuni gas sales reduced to ca. 20 PJ/annum, the surplus field deliverability was used for a gas re-injection scheme to accelerate condensate production.

During the 1980s and 90s, a number of additional Kapuni infill/appraisal wells were drilled and hydraulically fractured to maintain field deliverability and test previously untapped zones.

In 1991 BP decided to exit exploration and production activities within New Zealand and sold their Kapuni field share to the remaining two Joint Venture partners, with the result that Shell and Todd shares became aligned at 50% each.

In the mid 1990's, Todd was extremely active in the gas market, which resulted in new gas supply contracts to the 70 MW Fonterra/Todd Energy co-generation plant located at Whareroa near Hawera (1996) and Taranaki By-Products plant located near Okaiawa in South Taranaki (1999).

Due to the natural decline in field deliverability, gas re-injection ceased in 2001. Since that time Kapuni has seen a high number of well entry related activities over the last few years, with recompletion workovers, additional perforations, water shut-offs, hydraulic fractures, and the drilling of additional wells (KA-16, -17 and -18).

The current focus is on appraising the tight gas intervals located between the K1A and K3 reservoirs, with the first of a three well Tight Gas Pilot expected to spud in November 2012.

Field facilities

Kapuni facilities currently consist of 18 wells located on nine well sites around the centrally located Kapuni Production Station. Low Temperature Separation units are installed on the well sites to separate the gas from the liquids (condensate and water) and pre-condition the gas.

Via separate pipeline gathering systems, gas and liquids are transported to the Kapuni processing plant, where the bulk of the gas is diverted, without significant further treatment, for sale into the Vector-owned Gas Treatment Plant. Vector removes CO₂ from the gas and also recovers liquefied petroleum gas (LPG) and natural gasoline products. The in-field gas gathering system also feeds the pipeline to the co-generation facilities at the Fonterra dairy plant in Whareroa.

The liquid streams separated by the well sites facilities are treated in the Kapuni Production Station, which involves separation and stabilisation of the water and condensate phases. The water is disposed of via a water injection well, while the condensate is transported by a dedicated cross-country pipeline to Port Taranaki in New Plymouth. From there it is exported by marine tankers to refining destinations.

Field statistics

The Pohokura Field is located in the Taranaki Basin immediately offshore from Motunui (Waitara) in permit 38154.

Field history

The Field was first discovered in February 2000 with the drilling (by Fletcher Challenge Energy) of Pohokura-01 well 4.6 kilometres offshore in 30 metres of water. This well was followed by Pohokura-02 in May/June 2000. Analysis of tests from both wells confirmed the presence of hydrocarbons in commercial quantities.

These first two wells were later followed by Pohokura-03 and Pohokura South-01B to further appraise the field and improve the subsurface understanding.

In 2001 Fletcher Challenge Energy's assets were acquired by Shell Petroleum Mining. Currently, the Field is owned and operated by a joint venture partnership comprising Shell Exploration NZ (48%); OMV New Zealand Ltd (26%); and Todd Pohokura Ltd (26%).

Field facilities

First commercial gas flowed in September 2006 from 3 onshore extended reach drilling (ERD) wells in the southern part of the field. In March 2007 gas and condensate flowed from the first of offshore wells. 5 wells produce from the PPB platform which produces to shore via a 9km subsea pipeline. Both the offshore platform and on shore production plant are unmanned and are controlled via a control room at New Plymouth which is manned 24 hours a day, 7 days a week.

Finished product is delivered to the market from the production station by way of two sets of pipelines owned by Todd Energy and Shell/OMV for both gas and condensate.

A gas re-injection (GRI) project is nearing completion, and expected to be operational in late 2012. This project will not only accelerate condensate production, but also improve the gas and condensate ultimate recoveries. 

Field statistics

The Maari Field is located in the Taranaki Basin 80 kms offshore from South Taranaki in permit 38160.

The permit contains two producing fields. The Maari field is located beneath the Maari FPSO and wellhead platform, and the Manaia field is targeted by an extended reach well 7 km south west of the Wellhead Platform.

Field history

The Maari Field was first discovered in 1983 and was developed by Operator OMV New Zealand Ltd together with Joint Venture partners Todd Maari Ltd, Cue Taranaki Pty Ltd and Horizon Oil Ltd. The field came on stream in February 2009

Field facilities

The Maari Field consists of five production and three water injection wells, and an unmanned Wellhead Platform TiroTiro Moana. The Raroa FPSO (Floating Production Storage & Offloading) is permanently moored 1.3 km from the Wellhead Platform and is operated by Tanker Pacific.

Power, water injection and processing facilities are all located on the FPSO. Subsea flowlines for oil production and injection water link the FPSO and Wellhead Platform.

The joint venture is currently finalising an appraisal and infill drilling programme which will commence once a jack-up rig is available in New Zealand (~Q4 2013). 

Field statistics

The Maui field is located 35 kms off the Taranaki coastline. The field comprises two production platforms, Maui A and Maui B.

Field history

The Maui gas field was discovered in 1969 and was considered a monster field for its time. A joint venture consisting of Shell, BP and Todd Petroleum was responsible for the discovery and development.

Due to the size and cost of the development, government investment was sought which resulted in a government entity (later PetroCorp) taking a 50% interest in the project. Fletcher Challenge Energy later purchased this entity from the government.

Full production from Maui A began in 1979, with 14 wells drilled from the platform in a water depth of 110m (a deep water platform for its time).

Maui B was installed in 1992 to allow full drainage of hydrocarbons from the southern part of the field.

Oil was discovered in deeper reservoirs below the gas sands in 1993. The FPSO (Floating Production Storage & Offloading) Whakaaropai was installed in 1996 and produced until decommissioning in 2006.

In 2001, Shell bought Fletcher Challenge Energy and farmed out 10% of Maui to OMV New Zealand Ltd. Todd has a 6.25% interest in the field.

Field facilities

The field facilities are effectively split in five areas. These consist of:

The Maui B platform situated 15 km from the Maui A platform, in 103 m water depth. This platform is designed to be unmanned and remotely operated from Maui A. Maui B is connected to Maui A via an undersea pipeline through which gas and condensate are transported to Maui A for initial processing. A total of 12 wells have been drilled on Maui B.

The Maui A platform sits in 110 meters of water 35 kms off the Taranaki coast. Subsea condensate and gas pipelines connect Maui A to the shore based processing plant at Oaonui, where gas and condensate are processed after having gone through cooling and water separation plants on Maui A.

Maui Production Station onshore at Oaonui, where processing and treatment of gas occurs to bring it to pipeline specifications. Condensate is also treated and split into enhanced condensate and naphtha. LPG is removed and sold as either LPG mix or butane for export.

Paritutu Tank Farm is located at the port of New Plymouth. Processed condensate and associated products are stored here before shipping overseas or to the refinery at Marsden Point.

Field statistics