Knowing your fleet's AdBlue® usage lets you choose the right pack size, set a sensible reorder point, size an on-site tank and budget with confidence. You don't need special software. With a few numbers you probably already have, you can get a solid estimate in ten minutes.
Method 1: from diesel use
This is usually the most accurate method, because AdBlue dosing tracks how hard the engine works, and so does diesel use.
For SCR diesel engines, AdBlue consumption is typically 3–6% of diesel use by volume. So:
- Low estimate = monthly diesel litres × 0.03
- High estimate = monthly diesel litres × 0.06
If you have diesel records by vehicle, work each vehicle out separately, then add them up. Many operators use about 4–5% as a planning figure for heavy trucks, then refine it once they have their own AdBlue records.
Method 2: from kilometres
If distance is easier to get, use typical per-kilometre figures:
- Heavy trucks: roughly 1.5–1.75 L per 100 km (about 15–17 L per 1,000 km).
- Cars and utes: roughly 1–1.5 L per 1,000 km.
Multiply each vehicle group's monthly kilometres by the relevant rate. This method is less precise for work with lots of idling, as idling uses AdBlue without adding kilometres. Machines logged in engine hours, such as loaders and excavators, are better estimated from diesel use.
A worked example
Take a mixed fleet based at one depot:
| Vehicle group | Number | Km per vehicle per month | Rate | Monthly AdBlue |
|---|---|---|---|---|
| Prime movers | 8 | 12,000 | 1.6 L/100 km | 1,536 L |
| Rigid trucks | 6 | 5,000 | 1.5 L/100 km | 450 L |
| Utes | 10 | 2,500 | 1.25 L/1,000 km | 31 L |
| Total | about 2,020 L |
The workings: 8 × 12,000 km = 96,000 km, at 1.6 L per 100 km gives 1,536 L. The rigids cover 30,000 km at 1.5 L per 100 km, giving 450 L. The utes cover 25,000 km at 1.25 L per 1,000 km, giving about 31 L.
As a cross-check, suppose the same fleet uses about 45,000 L of diesel a month. At 3–6%, that suggests 1,350–2,700 L of AdBlue, and 2,020 L sits comfortably inside that range. At 4.5% it would be about 2,025 L, so the two methods agree.
Turning the number into a plan
- Daily use: 2,020 L ÷ 30 days ≈ 67 L a day.
- Safety stock: three weeks of cover ≈ 1,400 L.
- Reorder point: with a one-week delivery lead time, reorder at about 1,900 L (seven days of use plus the buffer).
- Storage: about 2,000 L a month is two IBCs a month, or a 5,000 L tank refilled roughly every two months.
Check that whatever you hold will be used well within its shelf life. AdBlue kept at or below 25°C lasts about 18 months, and less in hotter storage.
If your fleet works seasonally, such as harvest, construction peaks or end-of-year freight, run the numbers for your busiest month as well as an average month. Size storage and safety stock on the busy month so you are not caught short when demand is highest.
Refining the estimate with real data
Estimates are a starting point. Once stock is flowing, replace them with actual figures:
- Record every AdBlue fill by vehicle and date. A metered pump makes this easy; K24-type digital meters can be calibrated in the field, and pulse meters can feed fleet systems.
- Each month, compare each vehicle's AdBlue use to its diesel use.
- Investigate vehicles well outside the fleet's normal ratio. Unusually low use can point to a dosing fault; unusually high use can point to a leak or spill.
- Recalculate storage and reorder points when the fleet or its work changes.
Your first step today: pull last month's diesel total for the fleet and multiply it by 0.045. That single figure is a reasonable planning number while you gather better data. Or enter your own vehicles into the AdBlue usage calculator for a breakdown.
How Liquidia can help. Once you know your volume, Liquidia can recommend a pack size or on-site tank, with metered dispensing, remote tank-level monitoring and scheduled refills. Try the usage calculator or see bulk and on-site supply.