Seat is adding the new Ibiza TGI in the supermini’s range, a new eco-friendly version that burns CNG and claims to be more economical than diesel, petrol and non plug-in hybrid cars.

The Spanish automaker claims that the compressed natural gas-burning version of the new Ibiza emits on average 85 percent less nitrogen oxide and helps decrease CO2 emissions by 25 percent.

The powertrain of the new Seat Ibiza TGI is an updated version of the 1.0-liter TSI three-cylinder engine which gets specific chrome-nickel covered pistons adapted to work with CNG, reinforced valve seats for greater wear resistance, raised admission valves to improve the fuel’s circulation and finally a lighter turbocharger.

As you would expect, there are two fuel tanks onboard, one for 13kg of CNG and the other with a 40lt capacity for petrol. Unlike other CNG-fuelled models in the market, the petrol tank in the Ibiza TGI has the same capacity with the rest of the petrol lineup, giving it an impressive combined total driving range of up to 1194km (742 miles) before having to refuel.

The CNG tank is mounted underneath the boot floor (reducing its capacity down to 262 liters), with its filler neck sitting next to the petrol filler one under the classic flap, so the only way to spot the Ibiza TGI from the outside is through its badging.

The 1.0-liter engine produces 88hp (90PS) and 118lb-ft (160Nm) of peak torque. Paired to the standard five-speed manual gearbox, the new Seat Ibiza TGI is capable of accelerating from 0 to 62mph (100km/h) in 12.1 seconds and won’t stop until it hits 112mph (180km/h).

More importantly the new Ibiza TGI scores an official fuel economy of 56.6 mpg UK (5lt/100km) in petrol mode and 3.3kg/100km in CNG mode. CO2 emissions are rated at 88g/km. Filling the CNG tank up will only cost you 13 euros which is overall much cheaper than petrol in Europe. The cost savings become even bigger if you take into consideration that the compressed natural gas is more efficient compared to other fuels, requiring a smaller amount to produce the same energy.

Seat will make the new Ibiza TGI available with every trim level, including the sporty FR model. The Spanish automaker also offers CNG versions of the Leon and Mii models, and by the end of 2018 we also expect to see the Arona SUV joining the TGI lineup.