If you run SCR-equipped heavy vehicles, AdBlue® is a regular line item alongside diesel, tyres and servicing. Knowing roughly how much each truck uses helps you size storage, plan orders and spot a truck that is behaving differently from the rest.
The typical figures
AdBlue consumption is usually expressed as a percentage of diesel use. For most SCR diesel engines it is typically 3–6% of diesel use by volume. In distance terms, a heavy truck commonly uses roughly:
- 1.5–1.75 L per 100 km, or
- about 15–17 L per 1,000 km.
So a line-haul truck covering 3,000 km in a week would typically go through something like 45–50 L of AdBlue. Over a year at 150,000 km, that's in the order of 2,250–2,600 L per truck.
These are working averages, not guarantees. Your engine manufacturer's documentation and your own records are the best guide for a specific vehicle.
Why SCR trucks use AdBlue
SCR (selective catalytic reduction) is the system most heavy diesel engines use to meet emissions standards for oxides of nitrogen (NOx). AdBlue is injected into the exhaust, where the heat turns it into ammonia. In the SCR catalyst, the ammonia converts NOx into nitrogen and water.
The engine control system meters the dose according to how much NOx the engine is producing. That is the key to understanding consumption: anything that makes the engine work harder or run hotter generally increases the AdBlue dose.
In Australia, SCR has been widespread in heavy vehicles since the Euro V-era ADR 80/03, and the newer Euro VI-equivalent ADR 80/04 has been phased in for new heavy vehicles. Newer engines are calibrated differently, so a mixed-age fleet can show a spread of consumption figures.
What makes one truck use more than another
- Load. A B-double at full mass works the engine harder than a rigid running half empty.
- Terrain. Long climbs and hilly routes raise engine load and NOx output.
- Duty cycle. Stop-start urban delivery, line haul and tipper work all produce different figures.
- Idling. Extended idling uses diesel and AdBlue without covering distance, which pushes up litres per 100 km.
- Engine calibration. Different makes, models and emissions generations dose differently. Some engines are tuned for lower diesel use with more reliance on SCR, and use more AdBlue as a result.
- Ambient temperature. Hot or cold conditions can change how the system operates.
This is why comparing AdBlue as a percentage of diesel use is often more useful than litres per kilometre. If a truck's ratio drifts well away from similar trucks in the fleet, it is worth investigating.
Using consumption data in your fleet
Consumption figures are only useful if you track them. Practical steps:
- Record AdBlue fills by vehicle, the same way you record diesel. A dispensing system with a meter or pulse output makes this simple.
- Calculate the ratio of AdBlue to diesel for each truck each month.
- Look for outliers. A truck using noticeably less than its peers may have a dosing fault; one using much more may have a leak or a calibration issue.
- Use the fleet total to size storage and orders.
Something you can do today: take last month's diesel litres for one truck and multiply by 0.03 and 0.06. If that truck's actual AdBlue use falls well outside that range, raise it with your workshop. For a full-fleet estimate, try the AdBlue usage calculator.
Keeping trucks supplied
A truck that runs out of AdBlue will reduce power and may not restart once switched off, so running low is an operational risk, not just an inconvenience. Keep depot stock above a set reorder point and consider a few sealed drums for vehicles that work away from base. Quality matters too: contaminated or off-spec AdBlue can block injectors and damage the SCR catalyst.
How Liquidia can help. Liquidia supplies fleets with drums, IBCs and bulk tanker deliveries from 1,000 to 32,000 L, plus on-site tanks and dispensing equipment with meters. See bulk and on-site supply or browse pumps and meters in accessories.