PowerWiseCLEANER HOMES. BRIGHTER TOMORROWS.
LIVE SIMULATOR

Can a 5 kWh battery run an AC all night?

INTERACTIVE HOME BATTERY RUNTIME SIMULATOR

Lower bills Energy independence A cleaner tomorrow
YOUR HOME, LIVE 2 bedrooms
Building your 3D home

Connecting rooms and appliances…

READY TO EXPLOREDrag to rotate · tap appliances
10:00 PM0h elapsed
10:00 PM6:00 AM
100%battery charge
Appliances powered · no solar input
TRY AN EXPERIMENT

One click. A different night.

UNDERSTAND YOUR RESULTS

How the battery runtime calculator works

PowerWise estimates how long a home battery can power your selected appliances. Set the battery capacity, add ACs, fans and lights, and use each device's switch to compare different setups. The interactive house shows which appliances are powered.

Start with your setup

  1. Enter your battery capacity in kilowatt-hours (kWh).
  2. Add appliances and set their watts using their ratings or measured consumption.
  3. Choose Standard or Inverter AC. For inverter units, adjust the average-power assumption.
  4. Set a target runtime, then compare the estimate and required battery size.
THE ENERGY CALCULATION

Usable energy = battery capacity × usable charge fraction × efficiency

Runtime in hours = usable kWh ÷ average load in kW

Example: 5 kWh × 90% ÷ 3.65 kW ≈ 1.23 hours, or about 1 hour 14 minutes.

Battery runtime questions

Can a 5 kWh battery run an AC all night?

It depends on the AC's average consumption and the other loads. At 90% efficiency, a fully charged 5 kWh battery with no reserve provides 4.5 kWh of usable output. A single continuous 1,500 W AC would use that in about 3 hours. Lower average consumption can extend the estimate; adding other appliances reduces it.

How does the Inverter AC option change the result?

It applies an adjustable average-power factor to the AC's listed wattage. The initial 60% example turns a 1,500 W rating into a 900 W average load. It is an assumption you can change, not a promised saving. Real consumption depends on temperature, thermostat settings, room insulation and the AC itself.

Does the simulator include solar charging?

No. It estimates discharge from the starting battery charge with no solar input. You can adjust the starting charge, reserve and efficiency in Battery & load assumptions.

Why might real battery backup time be different?

This is a simplified energy calculation. Startup surges, battery health, wiring losses, inverter idle consumption and changing compressor loads can affect real performance. The inverter capacity check uses listed running watts and does not model startup surge. Use the results to compare assumptions, and check equipment specifications when planning an installation.

Do I need an account, and are my settings saved?

No account is required. Calculations run in your browser. Appliance settings are stored locally in that browser when storage is available; the tool does not send those settings to a server.

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TRANSPARENT BY DESIGN

Real numbers.
Not a runtime guarantee.

This is a real-time 3D home and a simplified energy-budget calculator. Every AC creates a furnished bedroom. Every installed lamp, fan, AC and fridge has an independent switch linked to its modeled power consumption. The same house can be rotated and zoomed in every configuration.

The calculation

Available output energy = nominal battery kWh
× (starting charge − reserve) ÷ 100
× discharge/inverter efficiency

Average load = sum of enabled appliance watts
× each appliance’s average power factor

Runtime (hours) = available output kWh ÷ average kW

Required nominal kWh = target hours × average kW
÷ [usable charge fraction × efficiency]

Read the assumptions

The defaults use continuous listed wattage, 100% starting charge, zero reserve and 90% discharge/inverter efficiency. Each AC has a Standard / Inverter selector. Inverter mode starts with an illustrative 60% average-power assumption, which you can adjust beside that AC. This is not a guaranteed saving. Listed running watts are still used for the inverter output-limit check; the fridge factor is in advanced settings. These are illustrative inputs, not manufacturer ratings. No kW-to-AC-tonnage equivalence is assumed.

Variable-speed ACs do not have one universal duty cycle. Ambient temperature, thermostat setting, compressor behavior, battery health, voltage, inverter idle consumption and wiring can change results. Startup surge is not modeled. The inverter warning checks the sum of listed running watts against the selected continuous output rating, not surge capability.

The battery animation stops at the configured reserve. When power is unavailable, appliance airflow, fans and room lights stop. An average factor changes the energy estimate; it does not reproduce a real compressor cycle. Solar recharge is not included. Decorative exterior lighting is scenery and is not an extra modeled load.

Controls & recording

Drag to rotate the house, scroll or pinch to zoom, or use Front, Angle and Orbit. Click a lamp, fan, AC or fridge in the house to switch that appliance. The Individual lamps & fans panel provides an accessible switch for every fixture. Use the playback timeline to explore battery charge at any point in the night. Click AC or fridge labels to switch them. Adding an AC adds its bedroom; a third AC creates the next floor. Plus and minus install or remove fixtures. Switching a lamp off leaves the fixture in place, extinguishes its bulb and local light, and removes its wattage from the load. Use Video view for a larger, cleaner recording layout. Space runs or pauses the simulation when you are not editing a control; Escape exits video view. No screen recording is started by this website.

Settings are saved only in this browser when local storage is available. The page also works without saving. The downloadable HTML bundles all its code and does not load libraries or fonts from the internet.