Yesterday we told you how police forces in Maryland had turned to green cars – and now you can add another force to the list, this time in Salt Lake City, Utah.

In an attempt to save both money and energy, the police department will be adding four or five hybrid vehicles to its 450 car fleet.

The decision to add the green cars to the fleet was not straight forward as each hybrid vehicle costs around $23,084 – some $4,000 more than a regular petrol powered car. However, the hybrid cars are also capable of achieving around 10 miles a gallon more than traditional police cars.

After some sharp mathematics, the police force determined that the initial outlay was outweighed by the money that could be saved at the pump – the department currently spends $1.5million on petrol every year.

The police department now plans to replace 20 per cent of its fleet with hybrid cars every year. With only 12 hybrids currently included in its stock, this will mean a massive turnaround over the coming years.