Pioneer's history has never been about standing still and we continually innovate and challenge the status quo to find ways to deliver value to our customers.
Once known as the Otago Central Electric Power Board; a community-owned organisation with exclusive rights to generate, distribute and supply electricity to the wider Central Otago. Amidst, the electricity industry reforms of 1999 Central Electric chose to sell its lines and retain its generation business to become Pioneer Generation Limited.
Today we are known as Pioneer Energy Limited reflecting a diverse portfolio of energy assets, products and investments throughout New Zealand.
The business has a long history of evolution with four enduring principles at its heart: Trust, Service, Community and Guardianship. As the business grows we acknowledge our heritage and celebrate the pioneering culture upon which the business was built.
1924 - George Power Station
On 14 January 1920, three residents of Roxburgh; T P Michelle, R George and J H Waigth Jnr, were discussing diverting the Teviot River through a tunnel to irrigate Roxburgh East. Mr George who was the chairman of the Ladysmith Gold Dredging Company (then considering liquidation) suggested the plant and water rights of the company might be suitable for supplying Roxburgh with power.
This was the first station built on the Teviot River. It was commissioned in 1924, originally operating with two generators, each of 125 kW output and driven by Francis turbines. In 1926 a third Francis machine of 500 kW was added to the scheme. 1966 saw the two original machines replaced by one 500 kW unit, driven by a Gilkes Impulse Turgo turbine. During extensive refurbishment in 2002, the two 500 kW machines were replaced by a single machine with 1000 kW capacity.
The George Station operates with a 117 m head.
1925 - Monowai Power Station
Further South, the Monowai hydro-electric power station lies on the banks of the Waiau River approximately 50 kms from Tuatapere. The station was officially opened by the Southland Electric Power Board on 1 May 1925 and bought by the Government in 1936. Before the Southland network was linked to the national grid in 1939, the station was of major importance to the Southland community. Pioneer purchased Monowai Station in December 2002.
Late 1920s - Wye Creek
The former Otago Central Electric Power Board purchased the Wye Creek plant from the Goldfields Dredging Company in September 1941, the transfer was made for £5,750. It was originally built by the Golden Terrace Extended Gold Dredging Company Ltd, which went into liquidation in 1929.
At this time, the Wye Creek Hydro Scheme was capable of producing 400 kW of energy. A further 1000 kW generator and turbine (formerly used at the Lower Roaring Meg Scheme) was added in late 1991 during a major refurbishment of the scheme. The original machine was replaced in 2011.
The annual generation for Wye Creek is 9 GWh.
1936 – Lower Roaring Meg Station
In 1930, surplus power available from Teviot was diminishing due to growth in the Teviot district and the increasing requirements of the Central Otago board. Around that time enquiries were received from two London-based dredging companies for supply of electricity. This enabled the Central Otago board to look seriously at setting up a scheme on the Roaring Meg.
The original Lower Roaring Meg scheme had an intake in the stream, giving a 304m head. The water was fed through 2.4 km of 762 mm and 609 mm concrete lined steel pipes, (now replaced with steel pipe) to two Pelton wheels, direct coupled to two 850 kW, 6,600 volt alternators.
Originally the Lower Roaring Meg Scheme had a generating plant of 1,700 kW. The station was upgraded in 1989 when a 2 MW Reliance Synchronous Generator was installed, replacing one of the Metropolitan-Vickers generators, increasing Meg's output to 3,000 kW.
A devastating flood in November 1999 inundated the power station. Generators and turbines could be saved and refurbished however the control equipment was completely destroyed and was totally replaced. The station resumed generation in July 2000.
1947 – Upper Roaring Meg Station
In October 1941, extension plans were discussed and a decision was made for a further station to be constructed at the head of the valley. The proposal was to construct a storage dam at the top of the hill and direct water through a pipeline to a powerhouse above the existing Lower Meg Station intake weir, this station is known as the Upper Meg
The station began producing power in July 1947.
1954 - Fraser Station
The original, temporary, generating plant was installed in 1948 as a joint venture between the former Otago Central Electric Power Board and Public Works Department. Plant was sourced from Nokomai and Auckland to hasten the development of generation while awaiting the delivery of what would become the permanent equipment.
The temporary plant produced 500 kW of energy, which was much needed to meet the extra demands created with the Roxburgh Dam construction. Work began on the present station in 1951 and was completed for commissioning in 1954. It has a maximum generation output of 3,000 kW.
The station’s water supply comes from the Combined Irrigation Companies (CIC) - owned Fraser Dam. The dam is a concrete arch type, 35m high, impounding a lake of 46ha. About 5km downstream is the intake to the pipeline, which is in the form of a 10m high concrete arch weir. From the weir is a concrete low-pressure pipeline 4.5km in length. Pioneer Generation began a ten-year pipeline upgrade programme in 1999. Each year a section of concrete pipeline is being replaced with continuous welded steel pipe. The steel penstock is 580m long.
The station’s electrical equipment was completely refurbished in 2001 to provide automatic control and monitoring. The dam and weir are remotely controlled.
The Fraser River Station is a different concept in design from others in New Zealand, there being no powerhouse building as such. All generating equipment is situated outdoors under large metal covers, a small building contains instrument panels and control equipment. It is believed that this station is the only one of its type in New Zealand.
The cost of the original development was shared between the OCEPB and the Crown on the condition that half the output of the station during the summer months be supplied free of charge to pumps on the Earnscleugh, Galloway, Ripponvale and Pisa Irrigation Schemes. In recent times this agreement has been renegotiated with the CIC representing the combined interests of the current owners of these four irrigation schemes.
1960s - Nevis generation feasibility
The Board started investigating hydro-electricity in the Nevis Valley in the 1960s. Land was purchased in the Nevis Valley in the late 1990s with a view to securing a potential site for a hydroelectric scheme of up to 45 megawatts. Current studies are assessing the viability of the scheme from an engineering, environmental and economic viewpoint.
1969 - Glenorchy Station
Due to the distance from the nearest point of supply at Queenstown and the nature of the terrain between there and Glenorchy, it was decided to build a local generating station and reticulate the district from that point. In April 1967, a workers' camp was established and with a waterpower licence having been received, construction began of a new generation station at the Oxburn (or Twelve-mile).
Despite heavy flooding several times during the course of the project, an intake dam and pipeline were constructed. The powerhouse was built, plant installed, and reticulation of the district undertaken for an official opening by 8 February 1969.
In January 1994 very heavy rain caused disastrous flooding throughout the district. The outcome for the station was the gravel riverbed rising to the top of the main door frame level of the powerhouse. A concrete wall now surrounds the powerhouse.
1972 - Teviot Bridge Station
The scheme was proposed in 1967 but due to long delays in obtaining approvals and other commitments at the time, development did not begin until June 1970 when tenders were called.
The station operates at a head of 91m. The penstock comprises steel pipes, with an overall length of 457m. The water supply originates from the spill at George Station, on the hillside above. This outflow is taken through a vertical slide gate to the penstock of Teviot Bridge. Provision has been made for an overflow outlet pipe at the George Station when the Teviot Bridge Station is off line.
1981 - Ellis Station
A waterpower licence was obtained for this station in May 1978, enabling the project to proceed. The station powerhouse is alongside the Teviot Bridge generating station. Installed in the station is refurbished plant purchased from the Dunedin City Council (ex Waipori Power Station).
The Ellis Station has two generating machines. These machines are driven by Boving Twin Pelton turbines, which were manufactured in 1942. The station produces a maximum output of 7,800kW.
1982 - Marslin Dam
Downstream and fed from the Onslow Dam, Marslin Dam is the second reservoir on the Teviot Scheme. During normal operation water is provided to the Michelle Station via a pipeline. In winter or other times of high-energy use extra water from the Marslin Dam is fed to the lower Ellis Station via a tunnel, which bypasses the Michelle Station.
Completed in 1982, staff engineers undertook the design work for the 17m high arch dam. A new technique for the time was employed in construction that involved the use of flat-plate hydraulic jacks being built into the central vertical construction joint in the dam sections. After the concrete had cured, 1,200 tonnes of pressure was applied by the jacks to force the two sections apart and into the rock walls of the valley. The gap produced was then grouted to hold the dam in this position. This method produced a safer design, which used less concrete than a conventional arch dam.
1982 - Michelle Station
The Michelle Station operates with one induction type machine of 1,600kW output, driven by a Francis turbine manufactured in 1981. Michelle station has a static head of 74 m.
Michelle’s water supply is brought from the Marslin Dam via a steel and concrete pipeline. The station has an overflow pipeline alongside the main penstock, which enables water to continue flowing to the lower stations when the Michelle Station is off line. Discharge and overflow water from the Michelle Power Station moves via a race to a head pond, the scheme’s third reservoir and day storage area for the lower Teviot stations.
1984 - Lake Onslow Dam
Over the last century the Teviot River has been dammed and the water used for mining operations, irrigation and the production of hydro electricity. Lake Onslow at the head of the river was created in 1890 by damming an area of land called the Dismal Swamp. The sharing of the water storage in Lake Onslow has been a feature of water resource use on the Teviot River.
A new Lake Onslow arch dam constructed in 1982 raised the level of the lake by five metres and drowned the original dam.
The water to power the five Teviot River stations flows from Lake Onslow.
A small 2kVA rated output machine was installed at Lake Onslow in 1984 to provide local power for control equipment and servicing of the Lake Onslow Dam.
1993 - Central Electric Ltd established
The ownership structure changed with the assets of the Otago Central Electric Power Board forming Central Electric Ltd.
1999 - Pioneer Generation Ltd established
In 1999 the trust-owned Central Electric Ltd sold its retail and lines businesses, with the proceeds being transferred into a new charitable trust, the Central Lakes Trust. The company retained the region’s generating assets and was renamed Pioneer Generation Ltd. The Central Lakes Trust retains ownership of Pioneer Generation Ltd. Dividends to the Central Lakes Trust assist the Trust’s support of the Central Otago community.
2003 - Falls Station
Falls Station is situated approximately 10kms east of St Bathans adjacent to Falls Dam which is at the head of the Manuherikia River. An agreement with the Falls Dam Irrigation Company was signed in May 1997 to allow the project to proceed.
Roadworks to provide access to the site began in December 2002 and a transmission line was built to take electricity generated to Ranfurly via the Oturehua sub-station. The construction of the powerhouse, which is a basic reinforced concrete structure, began early 2003. It has a removable concrete slab roof, to enable heavy items to be installed and removed by crane.
Water supply to the station is via a pipeline from Falls Dam. The dam is a rock fill structure built in 1935 for irrigation purposes; it is owned and operated by the Falls Dam Company. Water is brought to the station via a low level pipeline split off from the existing irrigation line. A siphon pipe joins the lower level supply to provide additional flow from crest level when the full flow is required.
The station has a maximum generation capacity of 1,250 kW.
2009 - Horseshoe Bend Hydro Station
Horseshoe Bend is a 4.3MW Hydro Electric station commissioned in May 1999. The station is on the Teviot River, approximately 15km east of Roxburgh. Horseshoe Bend is Pioneer’s 5th station to be built on the Teviot River. The site is approximately 600m above sea level, and subject to severe weather conditions.
The dam is of unique construction, being the first roller compacted concrete dam in New Zealand. Here, a stiff mix of concrete is rolled by machinery into place, rather than poured into forms and boxes. It incorporates a stepped spillway on the downstream face. A 180m long tunnel feeds the 830m of pipeline and penstock to the powerhouse with water from the dam. The majority of the pipeline is buried with the penstock being supported above ground on concrete pedestals.
The powerhouse itself is a steel framed structure on a reinforced concrete foundation, which includes support for the turbine and generating plant
Five kilometres of new road were constructed to the site and 6 kilometres of existing road upgraded, including construction of culverts and cattle stops.
Any possible adverse environmental impact of such a construction was kept to a minimum. The result is aesthetically very pleasant. The dam itself has won a Caltex Construction Award and was nominated for judgement before ACENZ and the NZ Concrete Society.
2009 - Horseshoe Bend Wind Farm
Situated adjacent to the Horseshoe Bend Hydro station the wind project consists of three 750kW NEG Micon wind turbines giving a maximum output of 2.25MW. The turbines have 45m high steel tubular towers and 44m diameter rotors giving an overall height of 69m. The turbines were commissioned in late 2009.
2010 - Kowhai Hydro Station
Pioneer's newest hydro electric power station on the Teviot River is the Kowhai. The station has a maximum generating capacity of 1.9MW and produces an estimated 5.5GWh of energy each year.
Construction commenced in mid 2009 and the station was completed and commissioned in December 2010.
The site of the power station is approximately 3.5km east of Roxburgh adjacent to the Teviot Irrigation Company (TIC) intake weir on the Teviot River. The pipeline and penstock associated with the power station runs from the Marslin Dam some 1.5 km upstream.
The new pipeline follows the route of the existing pipeline that supplies water to the Michelle Power Station from the Marslin Dam.
No adverse environmental effects are evident from the construction of the scheme.
2011 - Mt Stuart Wind Farm
The Mt Stuart Wind Farm was constructed from 2010 to 2011.The official opening was on the 15th June 2012, which coincided with Global Wind Day. The Mt Stuart Wind farm was completed before the proposed finishing date and also under budget. A total of 43% of the construction costs were spent in New Zealand with $2.22 million spent in the Otago region creating revenue for local businesses and communities. The Mt Stuart Wind Farm consists of 9 Gamesa 850kW wind turbine generators.
45 metre tubular steel towers support each nacelle and each rotor has three blades, 44 metres in diameter that harnesses the wind and drives the generators. At wind speeds of 14.5 km/h, the turbines start producing power and maximum generation is at wind speeds above 61 km/h. The Mt Stuart Wind Farm produces enough electricity to meet the needs of approximately 3195 households.
2012 - Acquisition of Energy For Industry Limited (EFI)
The acquisition of Energy for Industry (EFI) in 2012 strengthened Pioneer Generation's market position, increasing and diversifying the energy production assets beyond Central Otago which has given Pioneer a national presence. EFI specialises in build, own and operate investments for energy facilities on customer sites and currently has many long term customers with investments in the manufacturing, processing health and institutional sectors.
2015 - Acquisition of ECOsystems
ECOsystems was acquired by Pioneer Generation to grow its energy efficiency offering for customers enabling the business to provide a range of energy services including energy efficiency, design, optimisation, metering, lighting control and energy service agreements.
2015 Southern Generation Limited Partnership
In 2015 Pioneer Generation Ltd, The Power Company Ltd (TPCL) and Electricity Invercargill Ltd (EIL) came together to form a new wind generation investment partnership, being Southern Generation Limited Partnership (Southern Generation). Pioneer holds a 50% stake in the partnership with the other 50% held by TPCL and EIL.
Pioneer Generation Ltd manages the Southern Generation Limited Partnership and specialises in small hydro, wind and thermal generation and heat plant around New Zealand. Roaring Forties partners, The Power Company and Electricity Invercargill, own and operate the electricity networks across Southland and parts of Otago. They jointly own PowerNet who operate and manage those networks. TPCL has over 34,600 connected customers across Southland and West Otago area and is owned by the consumers connected to the network through the Southland Electric Power Supply Consumer Trust. EIL has over 17,200 connected customers in Invercargill city and Bluff township. EIL is owned by the Invercargill City Council, through its subsidiary Invercargill City Holdings Limited. TPCL and EIL also jointly own the OtagoNet electricity network.Pioneer Generation Ltd, The Power Company Ltd (TPCL) and Electricity Invercargill Ltd (EIL) came together to form a new wind generation investment partnership, being Southern Generation Limited Partnership (Southern Generation). Pioneer holds a 50% stake in the partnership with the other 50% held by TPCL and EIL.
In late December 2015 Southern Generation acquired from Nova Energy, the Aniwhenua Hydro Electric station in the Bay of Plenty. The first North Island hydro powerstation to be owned by the Partnership.
2015 Ecotricity Partnership
Pioneer added another joint venture Ecotricity limited partnership to its growing family of investment partnerships. Ecotricity is New Zealand’s only CarbroNZero certified electricity retailer with exclusive access to Pioneer Energy's CEMARS accredited renewable generation.