How Much Is This Costing Me?? - Electrical - DIY Chatroom Home Improvement Forum

 DIY Chatroom Home Improvement Forum How Much is this Costing Me??

 Thread Tools Tweet Share Display Modes
06-16-2010, 10:04 PM   #1
Member

Join Date: Jul 2009
Location: Sacramento CA
Posts: 258
Rewards Points: 252

How Much is this Costing Me??

I have a small minifridge in my garage under my workbench that I use for beer and waters for when I'm out working on the hotrod. The sticker on the back of the fridge says it draws 1.2 amps.

Can you folks look at my math and correct me if I'm wrong in my assumptions or methodology.

1.2A * 120V = 144 watts

144 watts * 12 hours (not sure how often it runs but it is quite warm in the garage) * 30 days = 52 kWh

52kWh * \$0.12/kWh = \$6.24/month

Does this sound correct? I'm just trying to evaluate whether or not it is worth keeping plugged in.

 06-16-2010, 10:10 PM #2 Civil Engineer   Join Date: Mar 2009 Location: Boston Posts: 5,832 Rewards Points: 5,246 Refrigerators rarely run more than 20 percent of the time, even in a warm garage. Other than that, calcs are fine.

 06-16-2010, 10:21 PM #3 Member   Join Date: Jan 2009 Location: South of Boston, MA Posts: 17,248 Rewards Points: 2,000 My fairly new 26 cu ft fridge is rated to use under \$100 of electric a year I'd say yours is using much less

 06-16-2010, 10:29 PM #4 Electrical Supplier   Join Date: Jun 2010 Location: Dayton, OH Posts: 205 Rewards Points: 150 your calculations are assuming the fridge runs 100%
 06-16-2010, 10:57 PM #5 Member   Join Date: Jul 2009 Location: Sacramento CA Posts: 258 Rewards Points: 252 I wasn't sure exactly how much it runs, so I used 12 hours a day to be conservative. So, if I use 20% instead of 12 hours/day, it ends up being \$2.50 a month or \$30/yr. That seems well worth it to me!!! What do you think?? The reason I asked is because my friend was trying to say it was costing me \$25 a month to run. Thanks for the input fellas!
06-16-2010, 11:03 PM   #6
Member

Join Date: Jul 2009
Location: Sacramento CA
Posts: 258
Rewards Points: 252

Quote:
 Originally Posted by LyonsElecSupply your calculations are assuming the fridge runs 100%
I assumed 12 hr a day. But I guess thats a bit much. 20% is probably a more realistic number thanks!

 06-17-2010, 06:13 AM #7 Electrical Contractor     Join Date: Jun 2004 Location: Newnan GA Posts: 8,164 Rewards Points: 972 \$30 a year to keep the beer cold is a super deal!!!!!!! __________________ Yes I am a pirate, two hundred years too late The cannons don't thunder, there's nothing to plunder I'm an over-forty victim of fate.
 06-17-2010, 06:55 AM #8 Member     Join Date: Jan 2009 Location: Nassau, Long Island, NY Posts: 349 Rewards Points: 268 There are products like the kill-a-watt that actually measure consumption over time (electrical, not beer consumption!) just plug one if those in for a week or two and you'll have real numbers to play with. One warning though... Once you've got one you'll want to measure the world! My family is ready to kill me for measuring just about everything! :-)
06-17-2010, 07:03 AM   #9
I=E/R

Join Date: May 2010
Location: Minnesota
Posts: 2,052
Rewards Points: 1,000

Quote:
 Originally Posted by jbfan \$30 a year to keep the beer cold is a super deal!!!!!!!

Depending on how the frig is built, you may be able to help it a little. If it has the condenser coils on the back, add some additional insulation around the sides. If the coils are built into the sidewalls then you can't do this.

06-17-2010, 08:08 AM   #10
Member

Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Rewards Points: 2,000

Quote:
 Originally Posted by mopowers So, if I use 20% instead of 12 hours/day, it ends up being \$2.50 a month or \$30/yr. That seems well worth it to me!!! What do you think?? The reason I asked is because my friend was trying to say it was costing me \$25 a month to run. Thanks for the input fellas!
My 26 cu ft fridge doesn't use \$25 a month

I think you could leave the door open & run it 100% & it would not use \$25 a month

06-17-2010, 08:10 AM   #11
Member

Join Date: Nov 2007
Posts: 384
Rewards Points: 414

Quote:
 Originally Posted by WaldenL There are products like the kill-a-watt that actually measure consumption over time (electrical, not beer consumption!) just plug one if those in for a week or two and you'll have real numbers to play with. One warning though... Once you've got one you'll want to measure the world! My family is ready to kill me for measuring just about everything! :-)
Yup, got one a few years ago and I am STILL using it To the OP, I pay \$0.22/kWh which is almost twice what you pay. I plugged my main fridge into a Kill-A-Watt and measured it for a month. End result was, the main fridge in my house uses \$6.80/month. It's energy star yes, but also in a cove so heat dissipation isn't ideal and being opened/shut frequently all day. If my main fridge at nearly twice the price per kWh is only \$6.80/month I think your \$2.50 is far more accurate for a small unit that's not opened/closed too much... probably even less.

The big hitters in my house are the AC (running on powersave 24/7 cost is \$68/month), De-Humidifier (in basement, average cost is \$31/month in summer), and dryer (it's 240v I can't measure, but I think mine costs \$1-2 each drying cycle. After having a baby and doing cloth diapers which require daily washing & drying our electric bill more than doubled and it isn't the washing machine). The big surprises was the washing machine, according to the kill-a-watt costs a little over a penny per load. Now I do laundry more often, and try to air dry.

You should pick yourself up a Kill-A-Watt too. http://www.amazon.com/P3-Internation.../dp/B000RGF29Q you tell it what price you pay for kW, plug the device into it, and it will tell you exactly how much so far, per week, per month, per year that device should cost... and the longer you leave it plugged in and measuring (for items that kick on/off like a fridge) the more accurate. It's fun to see exactly what's going on, and not so expensive you'll break the bank. I don't know why, but the only thing mine won't measure is our microwave, turn on the microwave and ERR displays on the screen until the microwave shuts off. Has no problems with anything else.

Last edited by Piedmont; 06-17-2010 at 08:34 AM.

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are Off Pingbacks are Off Refbacks are Off Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Wadsworth HVAC 41 01-15-2010 10:44 PM Hobb3s Building & Construction 10 04-07-2008 12:12 PM

Top of Page | View New Posts