More money to run 220 0r110

[Ken Fitzgerald]

Ken, again...no! MY meter reads ounces and pints.

And some day I'd like to help you test your meter............

[Marty Paulus]

That's strange. My wife calculates the cost of me doing work the same way...As so several of my friends.

[Andrew Yang]

Wiring/Receptacle Costs
I wired my workshop for 240V for my DC, tablesaw and jointer/planer this past year. I will say that while the receptacle prices are like 8x a standard 120V receptacles it's not a budget breaker. I would hope people can manage $12 versus $1.50. The breaker itself is nominally more but depending on how far your outlets are from the breaker, the wiring itself will likely over ride all the other costs.

Smart Meters
The average home in North America is supplied its electricity using two 120V lines. Utilities implementing Smart Meters are concerned with 1. usage profiling, 2. net usage, 3. remote access to meter data, and 4. commodity theft. It is not possible to distinguish 120V vs 240V usage within the home at the meter. It would be limited to detecting drops in overall voltage levels due to excessive draw. This is different than commercial/industrial metering where the focus is on the complex power, not the apparent power, so it is more typically metered in VA not kWh. The simplest household example of this is the CFL which has an apparent (and rated) power of 11W but a complex power of up to 23W.

Power/Heat
With respect to the comments saying "all" the incoming electricity is turned into heat, it is technically correct, but practically incorrect. It would be like saying all of the energy in the gasoline is turned into heat. Technically it is correct as all energy, as another poster intimated, eventually decays to heat, but the relative efficiency of turning energy into useful work defines what amount is redirected prior the decay. i.e. moving the car or blowing air. In this case, a typical blower will operate at between 60-70% efficiency, meaning that of the electrical energy utilized, 30-40% will be lost through various mechanisms and end up as heat prior to contributing useful work. The balance is put toward useful work before decaying to heat.

edit: the forum is a little wonky in showing replies to replies vs. replies to the thread

[Charlie Velasquez]

I will not address cost of 120 vs. 240. However, my electrician suggested I wire my motors with 220 if possible. He said it better "balances" my leads and I would be less likely to see lights dim or other things on the puny 60A panel in my shop. Have no idea if this is true, but he is a very respected electrician.

[Todd Willhoit]

The values I used were to show that there is a difference in kW used. I also mentioned that the voltage drops and final usage of power would vary depending on individual parameters and circumstances.

In either scenario, as evidenced by the voltage drop, power (I^2*R) is lost in the cable. Using the data provided in your post, the total power consumed is the same, though less is wasted in the cable int the 240V system. Without knowing more about the motor, one cannot tell if the higher load power of the 240V system actually results in more work.

Scenario A:

V(line): 120
A: 15
V(loss): 2.9
R(cable): 0.192 Ohm
P(load): 1756.5
P(cable): 43.5
P(Total): 1800.0


Scenario B:


V(line): 240
A: 7.5
V(loss): 2.4
R(cable): 0.320 Ohm
P(load): 1782.0
P(cable): 18.0
P(Total): 1800.0

[Chris Jackson]

I've run 220 through my shop with 10awg 3 conductor, and 30 amp NEMA twist-lock recptacles...the reality is I will most likely NEVER recoupe the cost of that material in my energy savings. As and engineer who has spent many hours running payback calcs for energy savings projects I'll tell you that in my area where I'm paying in the neighborhood of $0.40 a KWH peak season/peak hours none of my machines is demonstrating a significant savings even over a 3 to 5 year window...just my $0.02

[Bryan Wellman]

I will not address cost of 120 vs. 240. However, my electrician suggested I wire my motors with 220 if possible. He said it better "balances" my leads and I would be less likely to see lights dim or other things on the puny 60A panel in my shop. Have no idea if this is true, but he is a very respected electrician.

A Watt is a Watt is a Watt. Doesn't matter how it's getting to the motor 220/120.... I will say I agree with him to the degree that say you have a motor drawing 15A at 120v. That same motor wired for 240V will draw roughly 7.5A per leg. Thus you are balancing out your panel with the load spread across both vs. one of the two phases.

[Kevin W Johnson]

edit: the forum is a little wonky in showing replies to replies vs. replies to the thread

It has to do with the default forum view that happened with the upgrade. Look just above the post at the top of the page, on the right hand side, you'll see "display" with a down arrow beside it. Click on display, and a selection menu will apear, select "threaded mode", and problem solved. It drove me crazy too, till I discovered that.

[Joseph D'Orazio]

Ken, again...no! MY meter reads ounces and pints.

Ha ha, mine too friend, mine too.

So, just to recap, cause I am greenhorn and all, wattage is wattage and you aint using no more or less on account of a motor being 110 or 220, ¿que no? Less amps being pulled for the larger 220 machines, ¿que no?