Street lighting switch-off plan for Derbyshire
About 40,000 Derbyshire street lights could be switched off at night, as part of a county council proposal.
The council said switching the lights off between midnight and 05:30 BST could save £400,000 a year in energy bills.
Some main traffic routes, town centres, areas with high rates of crime or road accidents will be unaffected by the plans.
The authority said the move would also cut its carbon emissions.
There are a total of 89,000 street lights across the county.
The council said its energy bills had increased from £1.87m in 2006/07 to £2.47m in 2010/11.
Members of the council's cabinet will decide whether to approve a public consultation on the proposals at a meeting on Tuesday.