More than 9,000 lights will be switched off
More than two-thirds of a council's 14,000 street lights are to be switched off to save money.
Powys council had planned to plunge over a third of its lamps into darkness for a year, but it has voted to turn even more off to balance the books.
The council's annual street lighting bill is about £500,000, but it said that was set to rise by £175,000.
The decision to turn off more lamps will avoid an overspend on energy costs of £43,000.
However, what the council describes as "core areas", such as locations covered by CCTV, pedestrian crossings and trunk roads, will not be affected by the move.
In April, officials said soaring energy costs, coupled with a tight budget, had forced the council to adopt a "radical approach" to street lighting.
It had planned to shutdown 5,000 lights this year, and 6,400 in 2009.
But the council still faced an overspend on energy costs of £43,000 so it decided to increase the scale of the project.
It means two in every three street lights (9,380) in the county will now be turned off in affected areas.
Some councils in England, such as Buckinghamshire, Essex, Hampshire and Hertfordshire are already putting similar schemes on trial.
In Carmarthenshire, street lights on some public footpaths may be switched off after midnight to save on energy bills.
In April, the charity Help the Aged feared the move in Powys could affect the elderly, and it called on the council to consult the public before a decision was made.
The council staged a consultation exercise with town and community councils.