New red and blue light bars will be installed in place of old rotating lights on the car roofs. The new light bars use 5 percent of the power used by old lights.
Police national procurement manager Stan Pope said the older lights ran the risk of draining the car battery and power use was at saturation point.
The low profile design of the light bars will generate the greatest saving for the police by reducing the drag on vehicles and creating a fuel saving of around 8 percent.
The orange and blue design on older cars will also be replaced by a yellow and blue design to make vehicles more easily recognisable and visible.
The police put around 500 new uniform cars on the streets each year and the entire new-look fleet will be rolled out by the end of 2014.
