Rotherham Council maintains around 38,000 lamps on roads within its borders, a commitment that cost more than 1.3m in energy bills last year.
But in the face of Government budget cuts and heightened environmental concerns, the council's lighting engineers have been ordered to review how the service is run.
A recent study by the authority revealed that, on average, each street light costs 35 a year in electricity, despite using much more efficient technology than that used in homes.
The council burns around 14.5 million kilowatt hours of electricity a year, and in a report to be considered by councillors at a meeting on Wednesday, officers say this could be reduced.
Principal lighting engineer Allan Lewis and his team have re-examined the authority's policy, and conclude that switching off street lights on certain routes could have a major impact.
In his report, Mr Lewis says: "Switching units off is logistically very difficult especially in residential areas and may result in complaints regarding which units are chosen.
"Extensive consultation of residents, where affected, and the emergency services, should be undertaken to identify any potential problems.
"In spite of this, investigations are under way to look at the possibility of how switching off could be achieved and would be accepted on roads which have reduced vehicular or pedestrian traffic between midnight and 5.30am.
"Depending on the type and wattage of the units which could be considered for a part night switch off, mainly main routes with higher wattage, savings could be in the region of 20 to 30 per annum per unit.
"Initial thoughts are that around five per cent of the network could be considered for switching off which would offer significant energy savings, but consultation and risk assessments will be undertaken prior to any installations being commissioned.
"Liaison with other similar and neighbouring authorities is being undertaken to ensure a consistent approach will be taken in trialling and implementing any areas of switch off and it is anticipated that trials will be in place by next financial year."
Rotherham residents may also detect a dimming of some street lights as part of the new policy, with engineers proposing that some of the brightest be fitted with new technology.
Successful trials have already taken place in the borough on street lamps according to Mr Lewis, and around 300 are already dimmed at certain times of night, saving 5,000 a year in electricity.
It is thought equipment which allows more lamps to be dimmed on major routes will be installed as part of a rolling maintenance programme.
Other ideas to reduce the cost of street lighting include the extended use of more efficient "white light" bulbs in street lamps, which offer "considerable energy savings" when compared with standard lights.
Work is also ongoing to assess the suitability of light emitting diode (LED) technology which run for around 10 years without the need for any maintenance at at much lower energy levels.
Areas of north Nottinghamshire, including the villages of Misterton and Everton near Doncaster, have also been earmarked by county council engineers for street light switch-offs.
The move has proved controversial among many residents, and local Labour MP John Mann has described the plan as "penny pinching of the worst kind".