A higher risk of interruptions to the electricity supply "than would normally be considered acceptable" will arise this winter and in 2001 when demand for power is at its highest, the ESB has said.
But the company said it would use imported power from Northern Ireland, rescheduled plant maintenance and short-term maximisation of plant capacity to address an expected shortfall of about 300 megawatts (MW) this year and next.
The ESB also expects the introduction of a voluntary demand reduction initiative to reduce demand this year. "The option of introducing new standby generators is also being considered," it said in a document on generation capacity requirements submitted to the Commission for Electricity Regulation.
The company said the addition of major new generation plant was essential after 2001. However, additional capacity of some 800 MW is likely to be available in 2002 as new generation plants operated by the ESB and by independent electricity suppliers begin. In its median projection, the ESB said some 1,000 MW of additional generation capacity would be required in the next six years.
While the ESB's existing peat-fired generation plants in the midlands will be closed in 2005 and 2006, the company also warned that other generation stations may be closed if a "significant level" of new generation capacity leads to a power surplus.
Using capacity on the North-South interconnector was considered to be a "contingency measure" to cater for short-term problems, so power imported on the interconnector was not included in the projections. However, the reality is that some 200 MW of capacity generated in the North is available for use here. A further 100 MW of capacity generated in the North is expected to be auctioned to independent electricity suppliers.
The ESB said the introduction of combined-cycle generation capacity at its Poolbeg plant would add 160 MW to its capacity this year, while its new peat-fired station at Edenderry, Co Offaly, would create additional capacity of 118 MW from next year. The company also estimated an increase in wind-generated capacity from 120 MW this year to 507 MW in 2006.