There are basically two types of water heaters. Those that run on gas and those that run on electricity. This applies to both traditional water heaters as well as the tankless units.

That being said, most water heaters require some electricity, even gas powered ones.
Does A Gas Water Heater Need Electricity?
Gas water heaters naturally use gas as it's primary source of power but, some models require electricity to get the pilot light burning.
So, yes, some gas water heaters do need electricity in order to operate.
How Long Will A Water Heater Stay Without Power?
The general rule of thumb is that if there is no power to a water heater, the water will only stay hot for about an hour or two.
But the rules change depending on the type of water heater that you have.
Electric Tank Water Heater
Because this unit's power source is solely electricity - then it will stop working when the power goes out. But the water that is in the reservoir will continue to stay warm for about 1 to 2 hours.
Gas Tank Water Heater
If your water heater model uses a continuous gas pilot light then it should work throughout the power outage.
But some gas units do require electricity (you will notice a power cord running from your tank into an outlet) - then just like the electrical models - your tank will stop working.
Tankless Electric Water Heater
Very much like the traditional electric water heater units - an electric powered tankless unit will stop working when there is an outage.
Tankless Gas Water Heater
The gas powered tankless units do rely on electricy so if there is an outage then this too will stop working.
We suggest that you speak with your plumber to identify other options (perhaps a solar power unit may work better for your locatoin).
If you have any questions about your water heater or are having problems with it, call Atlantis Plumbing today at 770-505-8570. We are available 24 hours a day, 7 days a week.
We Offer Water Heater Services in Metro Atlanta and Surrounding Areas
Fulton County, Bartow County, Cobb County, Paulding County, Cherokee County, Gwinnett County, and Douglas County.
Acworth GA, Atlanta GA, Austell GA, Cartersville GA, Doraville GA, Douglasville GA, Hiram GA, Kennesaw GA, Lawrenceville GA, Lithia Springs GA, Loganville GA, Mableton GA, Marietta GA, Powder Springs GA, Rockmart GA, Roswell GA, Smyrna GA, Tucker GA, Villa Rica GA, Vinings GA, Woodstock GA, and Surrounding Communities.