asked the Minister for Transport and Power the amount of electricity that is produced between midnight and 8 a.m.; if it is used economically; and if it is available to industry at cheaper rates during those hours.

I am informed by the ESB that electricity production between midnight and 8 a.m. is approximately 24 per cent of the daily production at present and varies between 20 per cent and 25 per cent depending on the time of the year and the day of the week. The daily output for a recent weekday amounted to 24,000,000 units of which 6,000,000 units were produced between midnight and 8 a.m.

The production of individual stations is continuously checked and adjusted by the ESB to ensure the most economic production of electricity consistent with security of supply. The economical use of electricity would be a matter for each individual consumer but the board through their advisory services assist consumers to make the most efficient use of electricity at all times.

Cheaper rates are available at night to domestic and to small commercial and industrial users, for process heating, water heating and space heating. Cheaper rates are available at night to larger industrial and commercial consumers for all types of usage.

If I heard the Minister correctly I take it that 24,000,000 units are produced at night of which 6,000,000 units are available for profitable purposes and 18,000,000 units are lost?

No, 24,000,000 units are produced in a 24-hour period of which 6,000,000 units are produced at night between midnight and 8 a.m. This is one particular day. It varies from day to day. It varies depending on the time of the year and the day of the week.

What proportion of the 6,000,000 units would be used profitably?

In the sense that the plant is there and the electricity can be produced for just the cost of the fuel at night, then it is produced profitably. There is no question of its being sold at a loss or as a subsidisation for another set of consumers.

Is there not a case to be made that the ESB should try to sell that current to somebody who might be glad to use it? It is there and it could be offered to them at an attractive price.

All industrial and commercial users know that by making use of the night time rate they can get it at a cheaper rate.

For how long can you retain or store electrical current?

You cannot store it. If that problem could be solved it would solve a lot of the problems from the point of view of capital investment in the ESB.

(Dublin Central): Can the Minister give any indication of when the cheap rate starts?

It is from midnight to 8 a.m.

In effect, is not current stored by the Wicklow development?

Not really. Turlough Hill uses the cheap electricity which is produced by the falling water during the day. This is to meet a peak demand at peak time. The electricity produced by other ESB units at night pumps that water back up into the pool and it drops down again at peak time.

Therefore, in effect, you are storing current?

No, water.