Protection and safeguard of our town’s environment and air: one of the main and common goals, essential for the human being’s health and the life quality improvement. This is a basic principle for STP, that has been replacing its buses fleet since 2006, buying new and less polluting vehicles.  

In particular 29 natural gas-powered buses are already on duty. The new methane-fuelled buses ensure lower pollution levels in terms of both gaseous and acoustic emissions, as well as energy outputs higher than the diesel and the petrol chain. Recently the company has bought 4 intercommunicating 18-meter buses, and they, too, are methane-fuelled.

In order to offer a term of comparison, it is important to know that: in one-year service (50.000 km) every old EURO 0 diesel-fuelled bus releases more than 8.000 kg of pollutants equal to 160 gr/km. In one-year service a new methane-fuelled bus, (much more powerful and air-conditioned), releases only 580 kg of pollutants equal to 11,6 gr/km. To sum up every 100 gr of pollutants released by the old buses, these methane-fuelled ones release only 7,25 gr of them.

The natural-gas powered buses on duty release altogether the same pollutants as a single old model vehicle, with a pollution reduction equal to 92,75% down for each bus.

And that’s not all, in fact the environmental benefit is considerable even within the acoustic field: the noise level released into the environment by an old EURO 0 diesel-fuelled bus is higher than 82 db(A) while the one of the new natural gas-powered vehicles is about 75 db(A); this means the sound pressure is reduced more than twice!  [- 3 db(A) correspond actually to a halving of the noise level released].

Last but not the least is another essential benefit in terms of operating economy, thanks to the intrinsic output quality of modern engines and the methane price lower than the diesel's one.