Iveco Stralis NP 6x2 on road

Switching from diesel to natural gas will produce a 10% saving in CO2 emissions for a heavy truck running on motorways, according to trials carried out by IVECO at Millbrook.

Speaking at the official UK launch of the Stralis Natural Power (NP) 460hp 6x2 Cursor 13-powered tractor unit, IVECO MD for UK and Ireland Stuart Webster said the new truck marked a “turning point” for gas vehicles in the UK, as 91% of tractor units registered in the UK are 6x2.

While Volvo is testing its gas/diesel 6x2 unit, IVECO is first to market and expects the 6x2 to sell substantially more than the 200 gas 4x2 tractors it has put on UK roads so far.

IVECO alternative fuels director Martin Flach claimed that natural gas trucks produce 90% less NO2 and 99% fewer particulates than Euro-6 diesel and that moving from conventional diesel to biomethane would cut CO2 emissions by 95%. The NP 460 can be switched to a quiet mode to achieve noise levels of 71dB(A) for night time deliveries.

While some larger operators will switch to gas for environmental reasons, Flach said the economic case was also proven, especially now the government had pledged to maintain the duty differential on natural gas below diesel until at least 2032.

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This means the next one and possibly two buying cycles for new gas trucks would certainly see a strong pay back, due to the lower cost of fuel.


This is despite gas trucks costing £30,000 to £35,000 more than their diesel equivalents, a cost gap that will narrow as volumes increase. Half this extra cost is in the special twin liquefied natural gas (LNG) tanks used on the 6x2 to increase the range to over 750km, significantly more than IVECO’s gas powered competitors Volvo and Scania.

NP range

Flach said IVECO’s stoichiometric combustion system was designed to operate at the chemically correct air/fuel ratio and used anti-knock software to ensure smooth running at all engine speeds.

Maintenance intervals for the NP range tractors are currently 90,000km and IVECO is hoping to extend this to 120,000km when a gas-specific engine oil becomes available. Spark plugs should last up to 150,000km but IVECO advises changing them at 120,000km.

Every one of IVECO’s 89 UK service points will have a ‘gas champion’ and service levels on repair, maintenance, parts and breakdowns will be exactly the same for gas and diesel trucks.

Iveco fuel consumption resized

IVECO is working closely with gas refuelling station operators and estimates there will be 400 open by the end of 2018 and a further 100 by the end of next year. The network is so far concentrated around main arterial routes such as the M1, M5, M6 and A1 but is gradually spreading across the UK. There is now one gas station in Scotland and small Glasgow haulier Gilmour Brothers have two gas IVECO trucks on the road.

The launch of the 6x2 now means that IVECO can offer gas vehicles from 3.5 tonne to 44 tonne, and it will launch a 460hp gas Stralis X-WAY construction truck early in 2019. It is also considering increasing the power output of the 13 litre gas engine to over 500hp for operators requiring higher horsepower tractors.

While it is investigating other fuels such as electric and hydrogen it believes natural gas will remain the only viable alternative to diesel power for heavy trucks for the foreseeable future. Its commitment to future fuels was demonstrated at the last IAA show in Hannover when its stand featured only electric, gas and hydrogen vehicles.


Ocado fleet services manager Graham Thomas is a convert to gas, and has been running five IVECO Stralis 4x2 tractors since August. He has a further 24 on order for his Hatfield depot where they will haul 5m high doubledeck trailers at 32 tonnes gvw.

He said moving from Euro-6 diesel to natural gas was “morally the right thing to do” and described how his first sight of the Stralis NP 400 in 2017 was a “game changer”.

“IVECO was streets ahead on gas so we started our journey,” he said. “We got a demonstrator straight away to get our drivers’ reaction, as we were an all-Mercedes fleet at the time.”

Ocado IVECO Stralis NP 4x2

He said the drivers “loved” the gas trucks, mainly because they were as easy to drive as diesels – despite having 30hp less – and much quieter. Thomas is running on compressed natural gas as the 600km range it provides is adequate for the majority of his routes.

Using Ocado’s own fuel consumption and cost figures he calculated he was saving £13,500 in running costs every year on each truck. “It is a no-brainer,” he said.