Electric vs. Gas Water Heater

Which is better Electric or Natural Gas Water Heaters?

One of the questions we are often asked here at Haley Plumbing deals with the differences between electric and gas water heaters.  I”ll try to lay out the pros and cons for you to help yo make an informed decision.


Electric water heaters, by any manufacturer, are 100% efficient.  This means that every watt of power put into the heating elements is transferred into hot water.  Gas water heaters range in efficiency from 70% to 98%.  Without any further information, the decision would be a no brainer.  The electric water heater wins.

Recovery Rate – Why Gas is so Popular

The recovery rate of a water heater is the number of gallons of hot water per hour that a water heater can produce.  The average residential electric water heater has two heating elements.  Each of these heating elements are capable of turning 4500 watts of electricity into 15,345 BTU”s (British Thermal Units, the scientific standard measurement for heat and 3.41 watts per BTU) per hour.  But, only one heating element is active at a time.  So, 15,345 BTU”s is the total out put.

Gas water heaters range from 30,000 to 50,000 BTU”s for the residential models.  If a sample gas water heater has a 40,000 BTU input rating and an 80% efficiency rate then, we find if has a 32,000 BTU total output.  This over double the output of the electric model.  The gas water heaters wins.

Cost of Operation

Now we come to the main reason that most homes and businesses use natural gas to heat water, cost of operation.  Natural gas has about 1,000 BTU”s per cubit foot.  My last gas bill charged me $.60 per 100 cubic feet.  So, I”m paying $.006 per 1,000 BTU”s.

Electricity is sold by the kilowatt/hour (KWh).  My last electric bill showed a rate of $.10 per KWh.  A kilowatt is equal to 1,000 watts.  A watt is equal to 3.41 BTU”s.  This comes out to $.029 per 1,000 BTU”s.  In this category gas is the clear winner.

I hope this article sheds some light on the differences between electric and gas water heaters.  If your home is already plumbed for gas, a gas water heater is clearly the way to go.  To have your water heater repairs or a new heater installed, call Haley Plumbing today at (281) 992-0400