The ESB should be split into three companies and its market share should be reduced to 40 per cent, a report on the future of the electricity market recommends.
The report by consultants Deloitte has been forwarded to the Department of Communications and other key players in the energy sector, but Minister for Communications Noel Dempsey has declined to publish it.
He wants to develop an overall energy policy document, which is expected to be published some time in the early summer.
Recently he said: "It makes sense not to publish a report into such a crucial part of the energy sector in isolation of the wider review which we are conducting."
Opposition politicians have accused the Minister of withholding the report because it contains several controversial suggestions about addressing the ESB's dominance of the market.
The report is believed to recommend that ESB transmission, power generation and customer supply all operate separately.
It says the current close links between the companies is seen in a negative light by potential private sector entrants. The report believes the dominance of the ESB in terms of generation capacity and output is a barrier to new players entering the market.
The ESB is committed to getting its share of the electricity market down to 60 per cent, but the report suggests a more aggressive target may be needed. If the company was forced to reduce its share to 40 per cent, it would be forced to sell off several power stations.
It is believed the report suggests the Government should consider this idea.
The transmission system is currently the responsibility of ESB Networks, a wholly owned subsidiary of ESB Group.
It operates a nationwide distribution system, which includes 170,000 transformers, and almost 150,000 kilometres of overhead lines and underground cables.
This division makes a significant contribution to the ESB's profits each year.
The supply/retail arm is the part of the ESB that sells electricity directly to customers, while the generation arm includes 19 power stations.
Some of these would be attractive to other buyers, but others suffer from low availability and are in need of regular maintenance.
