The Glendoe hydro power station halted power generation in August
A £140m hydro electric scheme will not generate power at all next year, its operator has said.
In August, a rock fall closed a tunnel carrying water from a hilltop reservoir to a massive turbine on the Glendoe project near Loch Ness.
Scottish and Southern Energy (SSE) said it was unlikely the plant would be running again until April 2011.
The company also said planning applications would be submitted for two new hydro projects in 2011.
The pump storage schemes planned for Coire Glas at Loch Lochy and Balmacaan at Loch Ness would be the first of their kind in Britain since 1974.
The plants use two bodies of water located at different heights.
During periods of low demand for power, electricity is used to pump water from a lower loch to an upper reservoir and this water is then released to create power at a time when demand is high.
A new tunnel may have to be built to bypass the damaged section at Glendoe.
The hydro scheme was officially opened by the Queen in June.