Backup power guides

Each guide answers one question in its first two sentences, then works a real example through the calculators and shows the numbers. Outside facts carry a source.

• How big a battery do you need to run a refrigerator during an outage?

  Worked through the home battery calculator, for one, three and seven days.

• Can a portable power station run a sump pump?

  A pump and a refrigerator for three days, and which portable stations cover it.

• Is a solar generator cheaper than a gas generator?

  A ten-year comparison from the solar vs gas calculator, with the working.

Or go straight to a tool: the home battery calculator or the solar vs gas calculator.