| Scenario | Battery | Preset | Debris | Filter | Duty | Estimated runtime |
|---|---|---|---|---|---|---|
| Dry leaves, short hose | 18 V, 5 Ah (90 Wh) | Eco | Light | Clean | 80% | ~18–22 minutes |
| Mixed debris, normal cleanup | 18 V, 6 Ah (108 Wh) | Standard | Medium | Partly | 75% | ~11–15 minutes |
| Wet leaves, long hose | 36 V, 4 Ah (144 Wh) | Turbo | Heavy | Clogged | 70% | ~7–10 minutes |
Battery energy (Wh) is computed as:
Battery_Wh = Voltage_V × Capacity_Ah
Effective energy (Wh) accounts for battery health, system efficiency, and temperature:
Effective_Wh = Battery_Wh × (Health%/100) × (Efficiency%/100) × TempFactor
Effective power (W) increases with garden load:
EffectivePower_W = BasePower_W × LoadMultiplier
Runtime (hours) uses duty cycle (trigger time):
Runtime_h = (Effective_Wh × Duty%/100) ÷ EffectivePower_W
Total runtime multiplies by the number of batteries available.
- Select Battery for cordless vacuums, or Mains for corded units.
- Pick a mode preset. Use Custom if you know watts.
- Set mulch density, filter condition, and hose length to match real work.
- For battery: enter voltage and Ah, or directly enter Wh.
- Adjust duty cycle to reflect on/off triggering patterns.
- Press Calculate to show results above the form.
- Use Download CSV or Download PDF to save outputs.
Understanding runtime drivers in garden vacuum work
Runtime is the practical time a vacuum sustains airflow while collecting leaves, mulch, or pond debris. The calculator estimates this by combining battery energy, power draw, and load factors. Airflow demand changes as bags fill, filters load with dust, and hoses extend. Use consistent inputs to compare setups.
Battery energy and usable capacity considerations
Battery packs are rated in volts and amp-hours, which convert to watt-hours (Wh). A 18 V, 5 Ah pack stores about 90 Wh. Usable energy is lower because of internal resistance, controller losses, and aging. The tool applies battery health and system efficiency to estimate effective Wh, then adjusts for temperature, since cold weather can reduce output. Record watt meter readings to refine the custom power input for accuracy.
Load multiplier effects from debris, hose, and filters
Garden debris behaves like a variable restriction. Wet leaves and heavy mulch increase suction demand, and a partly clogged filter forces the motor to work harder to maintain flow. Longer hoses add friction losses. The calculator uses a combined load multiplier so you can see how moving from clean to clogged filtration, or short to long hose, raises effective power and reduces minutes.
Duty cycle planning for realistic cleaning sessions
Few users hold the trigger continuously. Duty cycle represents the fraction of time the motor is running, accounting for pauses to reposition, empty bags, or clear jams. Entering 70-85% often matches typical yard work. For corded units, mains mode estimates active minutes per hour after breaks and reports kWh use, which helps with generator sizing and heat management.
Interpreting results to schedule efficient yard cleanup
Read the result as a planning window rather than a guarantee. If the estimate is 12 minutes per pack, plan a 10 minute work block with buffer time for bag checks. Add spare batteries to see total session time. Improving filtration, shortening hoses, and using Eco mode usually delivers more runtime than increasing speed.
What power draw should I enter for Custom mode?
Use a plug-in watt meter for corded tools, or manufacturer input watts if available. For cordless tools, estimate from similar models, then refine using observed runtime. Custom is most useful when your vacuum differs from the preset levels.
Why does a clogged filter shorten runtime so much?
As the filter loads with dust, airflow drops and the motor works harder to maintain suction. That raises effective power draw and heat, so the battery drains faster and the tool may reduce output to protect itself.
What is a realistic duty cycle for yard cleanup?
Many users run the vacuum in bursts while moving, emptying bags, or clearing jams. Start with 75–85% for continuous cleanup, or 60–70% for stop-and-go work. Adjust after one session to match your routine.
How do I compare two battery packs fairly?
Enter each pack’s voltage and amp-hours, keep the same preset and load settings, then compare runtime minutes. If you know the watt-hours printed on the pack label, enter Wh directly for the cleanest comparison.
How much does temperature affect battery runtime?
Cold conditions can reduce usable energy, while high heat can trigger protective limits. If you work below 10°C, expect shorter runs and consider warming packs indoors before use.
Is the load multiplier a precise engineering model?
It is a practical planning model, not a lab test. It captures common runtime drivers—debris heaviness, hose losses, and filter restriction. Calibrate it by matching one known job, then reuse the same settings for consistent estimates.