Why such a waste of electricity?

Residents and businesses are encouraged to conserve electricity so as to avoid the outages which we regularly have to contend with. Unless the roadside street lamps along the M4 are powered by solar, then I believe there is unnecessary consumption of electricity with roadside lamps along certain stretches.
Travelling south from the traffic lights on the M4 there is one lamp on either side of the road. Approximately 400 metres further south there are twenty four lamp posts to the SPCA turnoff. There are then 20 lamp posts before the circle of Zimbali Coastal Resort Northgate and only six on the south side.
Further along the M4 there is the Hilltop off ramp which had no lamp posts but there are 18 lamps within the fenced area running parallel with the M4 which are alight at night. Exactly what purpose are these lights serving?
Travelling further south there are 24 lamps before the Zimbali Fairmont circle off ramp and 24 further south.
The two circles along the Westbrook stretch of the M4 have six lamps either side, which are quite adequate to serve the illumination sufficiently.
There are in addition, flashing lights warning of the circles ahead.
One wonders where the funds are coming from to finance all the unnecessary electricity of the extra lamp lights and what capacity could be saved by reducing the number of lamps to six on either side of the circles.

NOLAN STONE
Ballito