Is it cheaper to run things on 220 Volts?

Real Estate Agent with DeLex Realty

In my 25 years as a contractor I do not know how many times I was asked this question. The answer is, no. In most cases (especially in non-industrial settings) voltage has zero effect on the cost of electricity used.

We are charged for electricity in kilowatt hours. A kilowatt hour is 1000 watts used over one hour of time. A watt is a measure of the electricity we have used, it is a constant and never changes (for the example of homes and most commercial buildings). We typically only use higher voltages to save money on copper wire. The reason is we measure wire size by amperage. Amperage is determined by wattage / voltage = amps, thus if we want to be able to use smaller (cheaper) wire, we must increase the voltage.

Knowing that wattage is constant and really measures the work performed, we can then know for a fact that in most circumstances (all that relate to homes), voltage will have NO affect on our power bill. Here is a simple example:

Let's say a hotwater heater is 5,000 watts. If we run it on 110 volts it will draw 45.46 amps. A circuit breaker is typically only rated at 80% of it's continuous load (the 5000 watts) so we would be required to install (by code) a 60 amp circuit. Knowing our wire tables a 60 amp circuit requires #4 wire which at the time of this writing was priced at $3.77 per foot. If we wire the same hot water heater at 220 volts we can use a 30 amp circuit and use #10 wire which is priced at 52 cents per foot.

Our wattage never changed but the cost of installation fell dramatically with the higher voltage. The hot wanter heater still uses 5,000 watts no matter what (or 5 kilowatts) which means every hour it is on, it uses 5 kilowatts of power. In my area, we pay around 7 cents per kilowatt so with this hot water heater we would pay about 35 cents per hour of use no matter the voltage.  

Posted by

James (Jim) Lord


Comments (3)

MichelleCherie Carr Crowe Just Call...408-252-8900
Get Results Team...Just Call (408) 252-8900! . DRE #00901962 . Licensed to Sell since 1985 . Altas Realty - San Jose, CA
Family Helping Families Buy & Sell Homes 40+ Years

Jim Lord thank you for the education about 220 voltage, you know your stuff.

Jan 19, 2017 10:47 PM
Jim Lord
DeLex Realty - Phoenix, AZ

Thank you, while I never really enjoyed the installation of electrical work, I always enjoyed the theory behind it.

Jan 20, 2017 07:18 AM
Joan Cox
House to Home, Inc. - Denver Real Estate - 720-231-6373 - Denver, CO
Denver Real Estate - Selling One Home at a Time

Jim, you do know your stuff, and learned more about electricity this morning! 

Jan 20, 2017 07:40 AM