An updated CNG system has been installed in the Korean manufacturer's i30, mated to its new 1.4-litre T-GDI engine and a new seven-speed dual-clutch transmission.
The power plant can use either petrol or CNG as fuel and automatically switches to petrol once the supply of CNG has been used.
When running on CNG, the engine develops 115bhp and maximum torque of 152lb ft from 1500rpm to 3500rpm. It emits CO2 emissions of 91g/km and meets Euro 6 emission standards, which aren't due to come into effect until 2017.
The CNG is stored in a rectangular tank within the floor pan, ensuring interior space remains the same as in the regular i30.
The tank is lined with a gas-impermeable polyamide matrix and cocooned in a high-performance glass-fibre reinforced plastic. It weighs 50 per cent less than an equivalent steel tank.
Up to 15kg of gas can be stored in the tank at 200 bar pressure. A new electrical pressure regulator lowers gas pressure to an operable state in two steps, first to 20 bar and then to 4 to 11 bar, which is fed into the engine.
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