Free Portable Power Station Calculator (NZ Camping & Home Backup)
Ever wondered what size portable power station you actually need?
I originally built this tool because I got tired of guessing battery runtime.
This free calculator takes the guesswork out of it in seconds.
Whether you’re:
- Camping around New Zealand
- Living van life
- Preparing for power outages
- Working remotely off-grid
This tool helps you find the right battery size for your setup without overpaying or underpowering your gear.
Try the Calculator
👉 Click below to launch the tool:
What this Calculator Does
This tool estimates:
- Your total daily power usage (Wh)
- Recommended portable power station size
- Minimum safe battery capacity (with buffer)
- Estimated runtime for common battery sizes
It gives you a clear, realistic range so you can confidently choose the right setup.
When researching portable power stations, I noticed manufacturers often exaggerate runtimes.
Don’t Know Your Appliance Wattage?
Use these common appliance wattage estimates to quickly calculate your total power needs.
Not sure how much power your devices actually use? Here are some common appliance wattage ranges to help you estimate your portable power needs more accurately.
Keep in mind that actual wattage can vary depending on brand, age, settings and efficiency.
Common Appliance Wattages
| Appliance / Device | Typical Wattage |
|---|---|
| Smartphone Charger | 5W to 20W |
| Laptop | 45W to 100W |
| LED Light Bulb | 5W to 15W |
| Wi-Fi Router | 5W to 20W |
| Electric Blanket | 50W to 200W |
| Portable Fan | 20W to 100W |
| Small TV | 30W to 100W |
| Gaming Console | 100W to 220W |
| Mini Fridge | 50W to 100W |
| Standard Fridge | 100W to 800W |
| Coffee Maker | 600W to 1200W |
| Microwave | 600W to 1500W |
| Toaster | 800W to 1500W |
| Electric Kettle* | 1500W to 3000W |
| Hair Dryer | 1000W to 2000W |
| Air Fryer | 1200W to 2000W |
| Portable Heater | 1000W to 2000W |
| CPAP Machine | 30W to 90W |
| Power Tool Charger | 50W to 150W |
*Note: Electric Kettles consume a lot of power, I lessen the overall power consumption by only filling with the amount of water required, there’s no point boiling more water than needed especially if only making a couple of cuppa’s
Quick Tip
Some appliances, especially fridges, pumps, and power tools can briefly use much higher startup wattage when turning on. Always choose a power station with enough surge capacity to handle these spikes.
Real-World Example
If you wanted to run:
- A laptop (60W)
- A portable fan (50W)
- Two LED lights (20W total)
Your estimated total usage would be around 130 watts.
That means a 500Wh portable power station could theoretically run those devices for around 3 to 4 hours depending on efficiency losses and battery condition.
Pro Tip for Better Accuracy
Check the label or charger on your appliance for exact wattage information. Many devices list:
- Watts (W)
- Volts (V)
- Amps (A)
If only volts and amps are shown: Watts = Volts × Amps
Example: 230V × 2A = 460W
Why Battery Size Actually Matters
This surprised me when I first started comparing solar generators…
Most people either:
- Buy too small → run out of power too fast
- Or buy too big → waste hundreds of dollars
This calculator helps you find the “just right” zone based on your actual devices.
No guesswork. No marketing fluff. Just clarity
How it Works (Simple Version)
- Add your devices (phone, laptop, fridge, etc.)
- Adjust usage hours if needed
- The calculator estimates your total energy use
- It recommends the best portable power station size for your needs
Who This is Perfect For
This tool is ideal if you are:
- Camping or road tripping in NZ
- Living in a van or tiny home
- Preparing for storms or outages
- Using CPAP or medical devices off-grid
- Trying to understand power station specs before buying
Recommended Power Station Range Guide
Here’s a quick guide based on results:
- Light use → under 300Wh
- Weekend camper → 300–800Wh
- Off-grid travel → 800–1500Wh
- Home backup → 1500Wh+
Pro Tip
If your result sits between two sizes, always choose the larger one.
Extra capacity:
- longer lifespan per charge
- more flexibility
- better emergency safety margin
Want Help Choosing a Power Station?
Once you’ve used the calculator, the next step is choosing the right unit.
We’ll be adding detailed recommendations soon, but for now you can compare brands like:
- EcoFlow
- Bluetti
- Jackery
Bluetti vs EcoFlow vs Jackery NZ: Best Power Station – Eco TIGA
Final Thought
Portable power doesn’t have to be confusing.
With the right setup, you can stay powered anywhere without overspending or guessing.
Frequently Asked Questions
What is a portable power calculator?
A portable power calculator helps estimate how much battery capacity or generator power you need to run your devices and appliances. It calculates total wattage and estimated runtime based on your selected equipment.
How do I calculate my power usage?
Add together the wattage of all the devices you plan to run at the same time. This gives you your total power requirement in watts.
For example:
- Laptop = 60W
- Mini fridge = 80W
- LED light = 10W
Total power usage = 150W
What does Wh mean on a portable power station?
Wh stands for watt-hours. It measures how much energy a battery can store.
A 500Wh power station could theoretically power:
- A 100W device for around 5 hours
- A 50W device for around 10 hours
Actual runtime may vary depending on efficiency losses and battery condition.
What appliances can a portable power station run?
Portable power stations can run many everyday devices including:
- Phones
- Laptops
- Lights
- Fans
- Mini fridges
- CPAP machines
- TVs
- Small kitchen appliances
High-wattage appliances like heaters and kettles require much larger power stations.
Why do some appliances have startup wattage?
Some devices need extra power when first turning on. This is called surge wattage or startup wattage.
Appliances like:
- Refrigerators
- Power tools
- Pumps
- Air conditioners
can briefly use 2 to 3 times their normal running wattage.
How accurate is this portable power calculator?
This calculator provides estimated results based on average wattage values. Actual power usage can vary depending on device efficiency, age, settings, and environmental conditions.
Can I use this calculator for solar generators?
Yes. This calculator can help estimate the battery size and output needed for solar generators and portable power stations.
What size portable power station do I need for camping?
For basic camping, many people use power stations between 300Wh and 1000Wh depending on what devices they want to run.
Small setups may power:
- Phones
- Lights
- Fans
- Cameras
Larger setups may support:
- Portable fridges
- CPAP machines
- Cooking devices
👉 Start with the calculator above and get clarity in seconds.