Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total pumping cost
$16,046
Cost per acre-inch
$20.57
Pumping hours needed
392.2
Fuel/energy consumed
4457.1
Input horsepower required
204.5
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How to use this
- 1Enter acres irrigated.
- 2Enter water applied (acre-in).
- 3Enter pump flow rate (GPM).
- 4Enter total dynamic head (ft).
- 5Enter pumping plant efficiency (%).
- 6Enter power source.
- 7Enter fuel/energy unit cost ($).
- 8Read your total pumping cost on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Pumping cost is driven by three things farmers often underestimate together: total dynamic head (lift plus pressure plus friction losses), pump and power unit efficiency, and the fuel or electricity price. This calculator uses the standard water horsepower formula, divides by overall pumping plant efficiency to get input horsepower, then converts to fuel or electric consumption over the hours needed to apply a target acre-inches of water. Diesel units commonly run 12-18% pumping plant efficiency for older engines versus 20-25% for well-maintained modern units, and that swing alone can double or halve your energy bill for the same water delivered. Use it to compare pumping costs across wells with different lift, or to justify a pump repower.
Worked example
Using the values the calculator loads with:
Inputs
- Acres irrigated: 130
- Water applied: 6 acre-in
- Pump flow rate: 900 GPM
- Total dynamic head: 180 ft
- Pumping plant efficiency: 20 %
- Power source: Diesel ($/gal, ~18 hp-hr/gal)
- Fuel/energy unit cost: 3.6 $
Results
- Total pumping cost: $16,046
- Cost per acre-inch: $20.57
- Pumping hours needed: 392.2
- Fuel/energy consumed: 4,457.1
- Input horsepower required: 204.5
What each field means
Inputs
- Acres irrigated
- The acres irrigated used in the calculation. Starts at 130 so you have a working example on load.
- Water applied (acre-in)
- The water applied used in the calculation, measured in acre-in. Starts at 6 acre-in so you have a working example on load.
- Pump flow rate (GPM)
- The pump flow rate used in the calculation, measured in GPM. Starts at 900 GPM so you have a working example on load.
- Total dynamic head (ft)
- The total dynamic head used in the calculation, measured in ft. Starts at 180 ft so you have a working example on load.
- Pumping plant efficiency (%)
- The pumping plant efficiency used in the calculation, measured in %. Starts at 20 % so you have a working example on load. Accepted range: 8–35 %.
- Power source
- Pick the option that matches your situation — the maths changes per option. Choices: Diesel ($/gal, ~18 hp-hr/gal), Electric ($/kWh, 0.746 kWh/hp-hr), Natural gas ($/therm, ~11 hp-hr/therm).
- Fuel/energy unit cost ($)
- The fuel/energy unit cost used in the calculation, measured in $. Starts at 3.6 $ so you have a working example on load.
Results
- Total pumping cost
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cost per acre-inch
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Pumping hours needed
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Fuel/energy consumed
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Input horsepower required
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What counts toward total dynamic head?
Add static lift (well depth to water plus elevation gain to the field), operating pressure needed at the pivot or gun (converted at 2.31 ft per psi), and friction loss in the pipeline, typically 5-15 ft depending on pipe diameter and length.
Why does pumping plant efficiency vary so much?
It bundles engine or motor efficiency, gearhead losses, and bowl/impeller efficiency together. A worn engine burning excess fuel, a slipping belt drive, and worn pump bowls each shave a few points off, and they compound. Nebraska Pumping Plant Performance Criteria tables are the standard reference for expected values by fuel type.
Is electric or diesel cheaper to pump with?
It depends entirely on local rates, but electric motors are inherently more efficient (90%+ motor efficiency vs 30-35% for diesel engines), so even with modest per-unit cost differences electric often wins if power is available at the well.
How much does raising the well pump help?
Every foot of head reduced cuts input horsepower proportionally. Dropping TDH from 200 ft to 150 ft (25% reduction) cuts pumping cost by roughly the same 25%, which is why declining water tables directly raise irrigation costs year over year.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Irrigation Pumping Cost Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/irrigation-pumping-cost
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/irrigation-pumping-cost" target="_blank" rel="noopener">Irrigation Pumping Cost Calculator — RevenueLab</a> (2026).</p>
Source: [Irrigation Pumping Cost Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/irrigation-pumping-cost) (2026).