UPDATE 1-Italy utilities to replace gas meters-regulator

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PISA, Italy Oct 23 (Reuters) - Italian utilities will have to replace a total of 20 million gas meters to meet the European Union standards and improve efficiency of gas distribution, chairman of Italian Energy Regulator AEEG said on Thursday.

Under the new regulation, due to be signed later on Thursday, utilities would have to install meters of new generation which measure gas consumption more precisely, AEEG Chairman Alessandro Ortis said on the sidelines of an energy conference.

Utilities would have to replace gas meters for big industrial clients within 26 months and within four years for households, the regulator said in a statement.

The new meters would have a capacity of remote reading of gas consumtion thus helping to avoid mistakes in measurement, the statement said.

Several Italian utilities have been under police investigation for defrauding customers as a result of meters charging clients for more gas than they really consume.

Earlier this month, Italian prosecutors requested Giuliano Zuccoli, chairman of regional utility A2A (A2.MI) and eight other people who worked with him when he was the head of Milan's utility AEM to stand trial for defrauding customers.

Zuccoli has said this week he is "calmly awaiting a decision of prosecutors. (Reporting by Svetlana Kovalyova; editing by James Jukwey)