Pump sizing calculator — industrial & solar water pumping
Estimate required flow, total dynamic head (TDH), hydraulic and motor power, VFD size, and — for solar mode — PV array kWp, panel count and optional battery buffer for agricultural irrigation, boreholes, greenhouses and pivot networks. Generate a prefilled RFQ with the calculated duty point.
How do you size an irrigation pump?
Pump sizing combines required flow with total dynamic head (static lift + friction losses + operating pressure). Hydraulic power kW = (flow m³/h × head m) ÷ 367, divided by pump and motor efficiency.
- Formula: kW = Q (m³/h) × H (m) ÷ (367 × pump efficiency × motor efficiency).
- Typical centrifugal pump efficiency is 0.65–0.80 at the duty point.
- Add filtration head loss (5–12 m) and 10–15% design margin.
- Variable-speed drives cut energy where demand varies across blocks.
Indicative only
- This tool is indicative only.
- It is not financial advice.
- It is not agronomic advice.
- It is not engineering design.
- Final numbers require supplier, agronomist, engineer and local regulatory review.
SeedMatch Group is an independent agricultural project sourcing and RFQ platform. We are not a farm, seed producer, fertilizer manufacturer, irrigation manufacturer, greenhouse builder, EPC contractor, lender or financial advisor. Supplier and project partner outreach is handled only after a commercial project brief is reviewed.
Supplier and manufacturer listings are provided for research, transparency and discovery only. SeedMatch Group does not provide automatic buyer-supplier introductions. Every agriculture project request is reviewed manually by David / SeedMatch Group, and supplier introductions are made only after internal approval.
Inputs
Sizing results
Generate prefilled RFQ- Daily demand
- 800 m³/d
Sizing a drip network? What is drip irrigation explains emitter flow, pressure compensation and filtration duty.
- Average flow
- 100.0 m³/h
- Peak (duty) flow
- 120.0 m³/h
Head build-up
- Static lift
- 15.0 m
- Pressure head (2.5 bar)
- 25.5 m
- Friction (15%)
- 6.1 m
- Total dynamic head (TDH)
- 46.6 m
Power & drive
- Hydraulic power
- 15.23 kW
- Shaft power (η 72%)
- 21.15 kW
- Motor (calc.)
- 26.44 kW
- Motor (standard frame)
- 30.0 kW
- VFD size
- 37.0 kW
First-pass sizing screener. Final selection requires a full hydraulic study (Hazen-Williams or Darcy-Weisbach), NPSH check, water-chemistry review and validated pump curves. SeedMatchGroup pairs your output with a normalised RFQ to qualified pump-station and solar-pumping manufacturers — supplier identities, curves and datasheets are shared through the private sourcing flow.
Frequently asked questions
- What does this pump sizing calculator estimate?
- Required peak flow (m³/h), total dynamic head (static lift + pressure + friction losses), hydraulic and shaft power, recommended motor kW with service factor, indicative VFD size, and, when solar mode is enabled, PV array kWp, panel count and optional battery buffer.
- How is total dynamic head (TDH) calculated?
- TDH = static lift (source-to-discharge elevation) + required operating pressure at the emitter / manifold (converted to metres, 1 bar ≈ 10.2 m) + friction losses along pipework. Friction is estimated from an assumed head-loss percentage on the pipe run; final selection requires a Hazen-Williams or Darcy-Weisbach hydraulic study.
- How is motor / VFD size derived?
- Hydraulic power (kW) = (Q × H × ρ × g) / 3.6e6, with Q in m³/h and H in m. Shaft power = hydraulic ÷ pump efficiency. Motor kW = shaft ÷ motor efficiency × service factor (typically 1.15). VFD is sized to the next standard frame above motor kW.
- How is the solar PV array sized?
- Daily water demand × hydraulic energy per m³ gives daily energy at the pump shaft. Dividing by peak-sun-hours and inverter/wire losses yields required PV kWp. Battery buffer, if enabled, sizes lithium capacity to cover a set number of no-sun operating hours at the pump's average duty.
- Is this a bankable engineering study?
- No. It is an early-stage sizing screener. For tenders, EPC contracts, or financing, SeedMatchGroup pairs the output with a full hydraulic and electrical package and a normalised RFQ to qualified pump-station and solar-pumping manufacturers.