Powys started turning off some street lights earlier in the week
Pembrokeshire is the latest county which might switch off non-essential street lights after midnight to save on energy bills.
Councillors have asked the county's cabinet to look at the measure which could save £213,000 a year.
If approved some street lights would be dimmed between midnight and 5.30am.
This week Powys began switching off two-thirds of its 14,000 lights but in Carmarthenshire similar plans have been dropped for the moment.
If Pembrokeshire's cabinet backs the switch-off areas covered by CCTV, pedestrian crossings and trunk roads would not be affected.
It will be considered by Pembrokeshire's cabinet on 6 October.