Written Answers. - Electricity Generation.

Wednesday, 24 November 1999

Dáil Éireann Debate
Vol. 511 No. 4

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  56.  Mr. Yates  Information on Ivan Yates  Zoom on Ivan Yates   asked the Minister for Public Enterprise  Information on Mary O'Rourke  Zoom on Mary O'Rourke   the statistics for the colour code alerts issued within the ESB when plant capacity is restricted and power cuts are likely; if these yellow and red colour code alerts are uniformly notified to her Department; if not, if she will arrange for the ESB to provide these statistics for each of the past 10 years; if the statistics show a sharp increase in the number of these incidents over recent years; and if she will make a statement on the matter. [24639/99]

  57.  Mr. Yates  Information on Ivan Yates  Zoom on Ivan Yates   asked the Minister for Public Enterprise  Information on Mary O'Rourke  Zoom on Mary O'Rourke   the statistics for electricity generation unit operations for the annual total plant availability for each of the past ten years; if these statistics show that there has been continued reduced availability of plant relative to capacity; if so, the reason in this regard; if up to 35 per cent of total plant is currently unavailable for electricity generation; if so, if this is the cause of the threats of power cuts; the steps, if any, being taken to ensure that there is adequate power plant maintenance to ensure that power cuts are kept to a minimum; and if she will make a statement on the matter. [24641/99]

Minister for Public Enterprise (Mrs. O'Rourke): Information on Mary O'Rourke  Zoom on Mary O'Rourke  I propose to take Questions Nos. 56 and 57 together.

It is useful to define what is meant by the terms “red alert” and “amber alert”. In layman's language a red alert occurs when there is a significant deviation from the normal operating standard signalling an “emergency state” in the power situation. An amber alert occurs when there is a contraction in the normal operating reserve caused, for example, by the tripping of a large generating unit. The issue of alerts are operational matters for ESB in the normal course and are not routinely notified to my Department.

The record of alerts for the past ten years as follows:

Year Amber Red
1989 13 3
1990 13 0
1991 10 1
1992 22 0
1993 11 3
1994 7 2
1995 10 1
1996 4 1
1997 3 0
1998 3 0
1998 26 1
1999 39 1

[942] Annual availability statistics are, by their nature, averages and not necessarily an accurate barometer of availability at critical periods.

The ESB has advised me that the following are the statistics for electricity generation in relation to total plant availability for the years 1989 to 1999:

1989 75.73
1990 77.29
1991 80.78
1992 79.87
1993 79.64
1994 82.94
1995 84.77
1996 86.21
1997 85.43
1998 84.30
1999 83.4 (estimate for full year)

These statistics show that the trend for plant availability steadily improved from a low of 75.73 per cent in 1989 to a high of 86.21 per cent in 1996. The trend has regressed somewhat since then.

The ESB endeavours to maintain an operating reserve of around 600MW at all times so as to provide cover against sudden increases in demand or sudden losses of generation plant. This requirement is particularly important in Ireland where the largest unit size is a relatively high proportion of the peak demand. Recently it has proved impossible to maintain the required operating reserve on a growing number of occasions for the reasons set out below.

The ESB has informed me that it is not correct that up to 35 per cent of total plant capacity is currently unavailable for electricity generation. Maintenance arrangements for ESB power plants are entirely an operational matter for ESB.

The principal reason identified by ESB for the recent reduction in availability and the recent upsurge in amber alerts was the increased level of unscheduled breakdowns that began in 1998 and continued in 1999. These outages arose from an unusually high level of faults in some of the larger generating stations. Having considered the nature of these faults, it is ESB's view that this high level will not continue.

I met the chairman of the ESB on 2 November 1999 about the electricity capacity situation. He gave me a categoric assurance that there would be no shortfall in the electricity supply during winter 1999 and 2000. I must accept that assurance.

As regards winter 2001, the Deputy will be aware of plans by ESB and a number of independent power companies to build new generating plant to come on stream around that time.

I will continue to monitor the situation.


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