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Producing electricity for Irelands Single Electricity Market

17 May 2017

SSE is the third largest electricity generator by capacity in the all-island Single Electricity Market (SEM). It owns and operates 1,870.5MW of generation capacity, of which 578.5MW is from renewable sources. This makes SSE the largest wind energy generator in the SEM. SSE owns and operates the 464MW Great Island CCGT in Co. Wexford, which is one of Ireland’s newest, cleanest and most efficient power plants. The company also trades across the interconnectors between Ireland and GB.

Performance in 2016/17

Energy Generation (Thermal)

In the 12 months to 31 March 2017, SSE’s 464MW Great Island CCGT station (grid connection capacity set at 431MW) exported 2.4TWh of electricity, up 40% on the previous year. The improved generation performance was due to increased power demand and prevailing market conditions, including the improved position of gas plant relative to other generation types.

As part of the Group’s impact assessment of the imminent changes to the Integrated Single Electricity Market (I-SEM) on the island of Ireland, it reassessed the value-in-use of its thermal generation portfolio in Ireland. This review concluded that the Group’s oil burning stations at Rhode and Tawnaghmore were impaired due to their age and future competitive prospects. The impairment for these assets amounted to £30.7m. The residual value of thermal plants in Ireland is £384.4m.

Energy Generation (Renewables)

Output of electricity from renewable sources decreased in 2016/17, compared to the previous year (1.46TWh compared to 1.54TWh). The primary driver for this differential was the weather; put simply there was lower rainfall and less windy conditions in 2016/17 than in the previous year. Overall renewable energy capacity increased, from 544MW to 578MW with the delivery of the 34MW Tievenameenta onshore windfarm in Northern Ireland which entered commercial operation in February 2017. Availability of the renewable energy portfolio to generate electricity remained high throughout the period.

Delivering and developing new capacity for electricity generation

SSE continues to operate under the policy support regime for renewable generation capacity in GB, currently delivered through the Renewables Obligation (RO) (which also applies in Northern Ireland); and the Contracts for Difference (CfD) mechanism. In Ireland support is provided via REFIT 2.

SSE has one onshore wind projects under construction which will qualify for NI RO:

  • Slieve Divena 2 (19MW) - construction of this project in Co. Tyrone is progressing well and is expected to be fully operational in summer 2017.

SSE has two onshore wind projects under construction which will qualify for ROI REFIT 2 support:

  • Galway Wind Park (SSE Share 120MW) – construction of this two-phase project totalling 174MW, making it Ireland’s largest onshore wind farm, is due to be completed by autumn 2017.
  • Leanamore (18MW) – a new addition is in Co.Kerry where construction is underway and is expected to be completed by the end of 2017.

SSE is continuing to advance its planning application for the Doraville development in Northern Ireland. In March 2017, SSE confirmed a new design layout which includes a reduction in turbine numbers and a change in turbine specification to optimise generation to 119MW.