Calculator
Power station runtime and size calculator
How long will a power station run your fridge, router or CPAP, and what size do you need?
Free tools
Free backup power calculators
Answer the big questions before you buy, such as how long a power station lasts, what size generator you need, which option costs less over 10 years, how ready you are, and what size to buy. They run in your browser, use sourced typical figures, and every number is editable.
Calculator
Generator size calculator
Add up running and starting watts the way generator makers do, and get a size.
Calculator
Generator vs home battery 10 year cost calculator
Compare the total cost of a standby generator and a home battery over 10 years.
Calculator
Solar charging time calculator
How long your panels take to recharge a power station, and how much charge you gain each day.
Calculator
Refrigerator runtime calculator
How long a power station runs your fridge, whether it lasts overnight, and the size you need for 24 hours.
Calculator
Power station cost per watt hour calculator
Type in the prices you are quoted and rank power stations by cost per watt hour.
Quiz
Outage readiness quiz
10 questions, a score out of 10 and a printable personal plan.
Reference
Appliance wattage chart
Running watts, starting watts and daily kWh for 104 appliances, US and UK, all sourced.
Finder
Power station finder
Your loads, outage length and budget band become a size and type recommendation.
Choosing a station to go with the maths? Read our power station for home backup buying guide, which works a full fridge, CPAP and router day from maker spec sheets.