Calculator
Generator Sizing Calculator
Estimate required generator kVA from hospital equipment load, power factor, load factor, and reserve capacity.
Calculator Inputs
Legend
Generator Sizing Calculator guidance
Required kVA = connected kW / power factor / load factor. Recommended kVA includes reserve margin.
Input meaning
- Connected load: enter the measured, quoted, or hospital-approved value in kW.
- Power factor: enter the measured, quoted, or hospital-approved value.
- Load factor: enter the measured, quoted, or hospital-approved value.
- Reserve margin: enter the measured, quoted, or hospital-approved value in %.
Result interpretation
- Use the result as a planning estimate, not as a final approval by itself.
- Record the assumptions used so Procurement, Biomedical, Facilities, Finance, and vendors can review the same basis.
Assumptions
- Generator sizing must be verified by a qualified electrical engineer.
- Motor starting current, harmonics, UPS charging, imaging loads, and code requirements are not fully modeled.
Biomedical use
- Use this calculator during RFQ preparation, technical evaluation, acceptance planning, service review, or biomedical workload planning.
How to identify the required values
Use these examples and common working ranges to choose values from gauges, labels, manuals, datasheets, RFQs, service reports, CMMS records, or hospital planning assumptions.
| Field | Example value | Common range | Tip |
|---|---|---|---|
| Connected load | Example: 100 kW. | Small department loads may be 20-100 kW; imaging or critical areas may be higher. | Include only loads intended to run on the generator. |
| Power factor | Example: 0.85. | Use 0.8-0.95 if not measured; final design should use measured or engineered values. | Use measured or engineered power factor for final design. |
| Load factor | Example: 0.8. | Common preliminary planning range is 0.7-0.9 depending on expected simultaneous load. | Use the expected simultaneous load factor, not the connected-load total. |
| Reserve margin | Example: 25 %. | Common preliminary generator reserve is 20-30%; higher values may be used for expansion. | Use expansion and starting-load margin agreed with electrical engineering. |
Common ranges are starting points for hospital planning. For final procurement, acceptance testing, electrical design, medical gas design, radiation shielding, dialysis water systems, or clinical use, replace the example values with site-specific data and vendor-confirmed figures.
Input Checklist
Confirm these values before relying on the output for procurement, PM, or service planning.
- Connected load
- Power factor
- Load factor
- Reserve margin
Safety And Engineering Notes
Use calculator outputs as planning estimates and verify critical systems with calibrated measurement or qualified engineering review.
- Generator sizing must be verified by a qualified electrical engineer.
- Motor starting current, harmonics, UPS charging, imaging loads, and code requirements are not fully modeled.
Related Calculators
Continue with calculators in the same biomedical planning area so estimates for power, gas, water, imaging, staffing, procurement, or lifecycle cost stay connected.
power
UPS Battery Backup Calculator
Estimate UPS backup time from load, battery voltage, Ah capacity, battery count, and inverter efficiency.
power
Battery Runtime Calculator
Estimate DC battery runtime from voltage, amp-hour capacity, load watts, and efficiency.
power
Power Consumption Calculator
Estimate daily and monthly energy consumption from equipment wattage, quantity, usage hours, and tariff.
power
ICU Electrical Load Calculator
Estimate ICU connected load and recommended electrical capacity from bed count, load per bed, fixed equipment, power factor, and reserve margin.
Related Equipment Hubs
Related Procurement Resources
Procurement guide
Medical Equipment Total Cost of Ownership (TCO) Guide: A Hospital Procurement and Biomedical Engineering Perspective
Many hospitals make procurement decisions based primarily on purchase price. However, the lowest-priced medical equipment is not always the most economical option over its operational life. Hidden costs such as consumables, service contracts, software licenses, spare parts, training, downtime, and equipment upgrades can significantly increase the true cost of ownership.
Procurement guide
Medical Equipment Acceptance Testing Guide: A Complete Hospital Handover and Commissioning Checklist
Medical equipment acceptance testing is one of the most critical steps in the healthcare procurement lifecycle. It serves as the bridge between equipment delivery and clinical operation, ensuring that hospitals receive exactly what was purchased and that the equipment is safe, functional, properly documented, and ready for patient use.
Procurement guide
Medical Equipment Service Contract SLA Guide
A medical equipment Service Level Agreement (SLA) is far more than a maintenance contract. It is a formal document that defines vendor responsibilities, response times, preventive maintenance requirements, spare parts support, reporting obligations, and performance expectations throughout the equipment lifecycle.