Diesel, gas, hybrid car? The "Kapo" knows its stuff.

The vehicle service of the Zurich Cantonal Police (Kapo) is by far the largest fleet operator in the cantonal administration. The fleet comprises almost 700 cars, vans, trucks, motorcycles and around 100 bicycles and e-bikes. For this reason, an early start was made on procuring environmentally compatible vehicles and making their operation as environmentally friendly as possible.

The Kapo's procurement policy is based on the directive "Reduction of vehicle emissions" (RRB No. 1425/2013), which requires that the vehicles of the cantonal administration be exemplary in terms of energy and environmental efficiency.

Alternative drives in the cantonal police force
With 22 natural gas vehicles, one electric vehicle and 38 hybrid vehicles, more than ten percent of the Kapo's passenger vehicle fleet currently has alternative drive systems. This means that the Kapo exceeds the overall Swiss fleet average of only 1.7 percent vehicles with alternative drive technologies by a factor of six. However, there are numerous modern diesel vehicles (Euro5/Euro6c) in the vehicle fleet due to relatively low consumption and thus lower greenhouse gas emissions.

Due to the "legal" and illegal manipulations by vehicle manufacturers, but also due to the NEDC test procedure, which is not in line with practical requirements (see infobox), diesel vehicles have fallen into disrepute with the public over the past two years. The cantonal police follow the credo of demanding a vehicle adapted to the intended use when procuring it, giving preference to gas, hybrid or electric vehicles where this is possible on the basis of the supply and makes sense from the point of view of the intended use. This is the reason why it uses an above-average number of vehicles with alternative drives. At the same time, the vehicle service consistently pursues the strategy of reducing greenhouse gas emissions per kilometre driven.

Average fuel consumption down
Although the annual mileage increased by 26 percent between 2005 and 2016 (from 9.3 to 12.5 million kilometres), the fuel consumption of the cantonal police has remained unchanged overall over the past eleven years. As a result, the specific average consumption across the entire vehicle fleet in real driving use decreased by 28 percent (from 11.9 to 8.7 l/100 km). This resulted in a reduction in CO2 emissions of 19 percent per kilometre driven. Compared with 1990, the figure is as much as 26 percent per vehicle kilometre driven (see graph opposite).

Driving style influences consumption
Evaluations for the same vehicle models show that the driving style in particular, but also the load and the driving profile, have a major influence on consumption and thus on greenhouse gas emissions. In the case of twelve diesel vehicles of the same model examined, for example, the following varies

"For gasoline vehicles, fuel economy varies much more. »

the consumption between the highest and lowest annual consumption by 1.4 litres per 100 kilometres. In the case of petrol vehicles, consumption varies considerably more. The range between the lowest and highest consumption is four litres per 100 kilometres for a petrol model comparable to the diesel model under investigation! Courses in fuel-saving driving are effective here and will therefore be used in the future.

Disadvantages of electric and hybrid vehicles
Even today's highly praised electric vehicles have ecological disadvantages. Although these are not perceived when driving in the canton of Zurich, they arise elsewhere in the world. For example, the production of the batteries is harmful to the environment. A recent study by the ILV Environmental Institute in Stockholm estimates that the current production of a lithium-ion battery produces around 150 to 200 kilograms of CO2 per kilowatt hour of capacity.

This would mean that an 85-kilowatt-hour battery (e.g. Tesla S) would already have a greenhouse gas impact of 17 tonnes of CO2 ex works, which would roughly correspond to the greenhouse gas emissions of an economical combustion engine in a good eight years. However, the electricity mix used to operate electric vehicles also plays a key role:

If mainly European electricity with a high fossil production share is used, the operation of an electric vehicle is less environmentally friendly than with the Swiss electricity mix with a high share of electricity from hydropower.

Optimisation through sustainable procurement
There is still much that can be done to optimise the environmental performance of both internal combustion engine and electrically powered passenger vehicles. The cantonal police will continue to do so. In the successive replacement of the fleet, it is consistently paying attention to the implementation of its strategy for the reduction of greenhouse gases. Thus in

In the future, efficient diesel vehicles with particulate filters will still be justified if they have nitrogen oxide emissions that comply with the regulations in real-world operation (from Euro standard 6d TEMP).

New vehicles will continue to be procured in accordance with the state of the art and, wherever possible, with alternative drive systems. Increasing use will also be made of renewable energy and refuelling with 100 percent biogas will be continued. The greenhouse gas balance of the Kapo fleet, but also the air pollutants emitted, should therefore continue to reduce - albeit not as rapidly as in the past 10 to 15 years.