Seat Leon ST TGI - Barcelona to Madrid for €20

The methane-powered Leon, just like its siblings in the VW Group – the Golf TGI BlueMotion, the A3 g-tron and the Octavia G-TEC – is powered by a 1,4-litre TSI engine generating 110 PS. It features a full-sized petrol tank for greater autonomy, but obviously using CNG yields better results, both in terms of economy and environmental performance. Just to give you an idea how eco-friendly the Leon ST TGI actually is, let us tell you the car only spews out 94 g of CO₂ per kilometre in CNG mode. That's roughly the same as boasted by the smallest city cars featuring downsized three-pot engines.

© SeatWait, the bottle in the trunk cannot be the CNG tank... And indeed it isn't

All the while the Leon ST TGI is a compact estate capable of comfortably carrying a family and a load of luggage. And it can do it cheaply, too – covering the distance from Barcelona to Madrid for as little as 20 euros (approx. 22,6 dollars)! If that leads you to thinking the two cities are a walking distance away and the low cost fails to impress you, be advised that Barcelona and Madrid are 615 km apart! According to Seat – or, actually, to Andrew Shepherd, a CNG expect employed by the Spanish carmaker – using natural gas will save you 50% compared to petrol and 30% compared to diesel.

Somehow, CNG still seems to have trouble catching on in Europe, although it's wildly popular in Argentina, Iran, Pakistan or India. As far as the Old Continent is concerned, methane only enjoys some tangible interest in Italy (over 800 thousand cars) and Germany (approx. 100 thousand cars). Will more countries follow? Probably. The question is: when?