AdBlue: making trucks greener

The transport sector is undergoing a transformation as it shifts towards electric vehicle (EV) technology. However, internal combustion engines will still be with us for quite some time – which isn’t a bad thing. Cleaner diesel combustion engines are already playing a pivotal role in driving the industry towards a more environmentally friendly future. Without AdBlue, this journey to greener pastures is impossible.

The shift to electrification cannot happen overnight, and will necessitate a major overhaul of the transport landscape, including increasing the nationwide recharging network. On the road to our electrified future, the modern combustion engine has a critical role to play. “Although electric drives in commercial vehicles will soon be as normal as the smartphone in your pocket, the combustion engine is still needed and is being further developed,” says Livingstone Mulaudzi, head of product management at MAN Automotive (South Africa).

“The MAN diesel engines now in use will be even cleaner and more economical than ever before, and AdBlue – used with our 5 and 6 engines in South Africa – is central to this ‘cleaner diesel’,” Mulaudzi expands. “Our modern diesel engines that require AdBlue benefit the environment directly with every new vehicle put into service.”

So what exactly is AdBlue? “This is a non-hazardous, biodegradable product – made from demineralised water and urea – that works alongside Selective Catalytic Reduction (SCR) technology to convert harmful nitrogen oxides (NOx) in emissions into harmless nitrogen and oxygen,” says Mulaudzi.

AdBlue functions with most modern diesel engines, which utilise SCR to reduce emissions. “The product is injected from a dedicated AdBlue tank into the exhaust line upstream of the SCR catalytic converter, he continues. “Under heat, urea decomposes into ammonia, which reacts chemically with NOx to convert them into nitrogen and water vapour. This is a major step in improving air quality and shows the commercial vehicle industry’s commitment to a greener future.”

The most important consideration for drivers is that AdBlue is not an additive, nor a fuel in its own right. It should never be added to the diesel tank,  and neither should diesel be added to the AdBlue tank.

Regulations require the AdBlue warning light to come on long before the tank runs dry, so drivers should never have to worry about running out on the road. After the first warning light, there are several further visual and audible warnings, followed by electronic engine performance limitations. “If all these warnings are ignored, the vehicle will eventually be immobilised and the engine won’t start until the AdBlue has been topped up, so it makes sense for drivers to carry an emergency AdBlue container,” advises Mulaudzi.

“Considering the various vehicle warnings and performance checks, it is highly unlikely a driver would ever find themselves in that position in the first place, but such an emergency measure would significantly extend the trip to the nearest refuelling point. For MAN trucks, the fuel tank capacity is in general proportionally matched to the size of an AdBlue tank, so that the two are topped up together. In some cases, the AdBlue tank capacity is higher than required, in order to avoid situations where AdBlue runs out before the main fuel (diesel).”

AdBlue is available at major MAN dealerships and, according to Mulaudzi, represents the future of diesel-based trucking. “AdBlue will become a way of life in the truck business. It doesn’t negatively affect total cost of ownership (TCO); in fact, it improves fuel consumption by up to 5%,” he asserts.

MAN’s TGM and TGX ranges boast Euro 5 and 6 engines, which both require AdBlue to function, and Mulaudzi emphasises that while South Africa is still a Euro 2 market, MAN is taking a longer view: “Not only does MAN make the country’s most economical trucks – a fact proven at Truck Test 2022 – but we also pride ourselves on being environmental champions. We are committed to bringing the most environmentally friendly vehicles to this country, so we are already investing in Euro 6 technology,” he reveals. “Customers can be reassured that it is neither costly nor massively inconvenient to introduce AdBlue into a fleet, and the environmental benefits are truly significant.”