Your result
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Enter your values, then click Calculate result.How this calculator helps
Plan the direct fuel expense of generator backup using the operating hours and consumption rate for your machine at the expected load. The result shows daily litres, daily expense and a 30-day monthly projection.
How to use it
- 1
Use the fuel-consumption figure at the load you actually expect, not only the maximum rating.
- 2
Enter daily generator runtime and the current price for the correct fuel type.
- 3
Add maintenance, oil, filters and repairs separately when budgeting total ownership cost.
Formula and methodology
Daily fuel = operating hours × litres consumed per hour. Daily cost = daily fuel × fuel price. Monthly cost = daily cost × 30.
Uses the values you enter with transparent energy, power and efficiency relationships. Provider tariffs and equipment specifications should be replaced with current figures.
Worked calculation example
A generator running four hours daily at 1.5 litres per hour consumes six litres per day. At PKR 280 per litre, that is PKR 1,680 daily before maintenance.
How to interpret your result
Use the projection to budget fuel and compare operating schedules; do not treat it as a generator efficiency guarantee.
Input guide
Use fuel consumption measured near the expected load.
Enter actual daily operating hours.
Use the correct current fuel price and add maintenance separately.
Scenario comparison
| Scenario | What it demonstrates |
|---|---|
| 1 litre/hour for 4 hours | 120 litres over 30 days. |
| Half-load versus high-load operation | demonstrates non-linear consumption. |
| Intermittent outages | model expected operating days instead of assuming every day. |
Common mistakes to avoid
- Using the no-load fuel figure for a loaded generator.
- Ignoring oil, filters and service intervals.
- Oversizing the generator and expecting proportionate efficiency.
Confirm the manufacturer's load-consumption curve and service schedule.
What can affect the result?
Electrical load
Fuel consumption changes significantly between light, normal and full load.
Engine condition
Poor servicing, clogged filters and worn components can increase consumption.
Fuel price
Petrol and diesel prices can change, so refresh the input before decisions.
Limits of this estimate
The calculator assumes a constant hourly burn rate and excludes warm-up, variable loading, maintenance, depreciation and generator efficiency curves.
Sources and review information
Frequently asked questions
Is the generator fuel cost calculator free?＋
Yes. SolvePilot tools are free, work in your browser, and require no account.
Does SolvePilot store my values?＋
No. Calculations run locally in your browser and the values you enter are not sent to a server.
Should I treat the result as an exact bill or quotation?＋
No. Results are informed estimates. Final charges can vary because of taxes, tariffs, lender terms, usage patterns, or provider rules.
How can I improve the accuracy?＋
Use recent values from your own bill, statement or institution, review every assumption, and confirm important results with the relevant official source.
Why does generator consumption change with load?＋
Engines burn more fuel as electrical load rises, and very light loading can also be inefficient.