Saving money on electricity

cute fuzzy bunny

Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Joined
Dec 17, 2003
Messages
22,708
Location
Losing my whump
I've been curious about how much electricity some things use, so I bought a thingy called a "kill-a-watt". There are similar products to this such as lacrosse's "power controller" which doesnt actually control anything.

Basically its a hand-sized brick that plugs into an outlet, you plug a 120v appliance into it, and it can tell you things like watt usage, or over periods of time will tell you kwh usage of the appliance. So if you connect a tv to it, turn on the tv, it'll tell you how much of a watt drain it is. Plug your dishwasher into it, run a load, and it'll tell you how many kwh a load of dishes costs to run; multiply by your utilities electric rate and you now know how much comes out of your wallet for a load of dishes.

I had a few surprises when I tested about half the stuff in the house. My tv's are pretty 'lean'. All are big screens in the 50-65" area <insert tim allen noises here>, but use about 130-150 watts when on. Most of the stuff that uses transformers take nothing when off (some transformers, cheap ones, can use the same electricity when plugged in and the powered device isnt even connected), and fairly nominal use when on. We have a video camera and monitor in the babies room so we can see what he's up to when he's sleeping without opening the door. We were regularly turning the thing on and off figuring it used a good bit of electricity. 10 watts. Hardly worth the wear and tear on the on/off switch.

The refrigerator was only using about 60-80 watts when the compressor was running, but opening the door and turning on the light caused an extra 100 watts to be added...I thought the idea that a fridge uses less electricity than the light inside it to be a chuckle.

Bad surprises: the 18v recharger for my dewalt power tools uses 75 watts when theres a battery in it, even after the battery is fully charged. Our modest string of christmas lights uses 400 watts. Our dinky tree with two small strands of lights on it sucks down 100, while our cool $20 6' tall fiber optic tree only uses 25. The computer takes ~200-250 during operation and surprised me by still using 125 while in standby mode. My color laser sucks down almost 1000 while its warming up and while printing, 25 while in standby. Our hamilton beach air purifiers were the big surprise...125 watts to basically turn a squirrel cage fan. We'd been running 3 of those almost full time. I think i'll be looking for a more energy efficient product. I figured our combo directv-tivo DVR's would be good for 80-100 watts plus, and was surprised to find it only drawing about 40 watts.

Next i'm going to put it on the dishwasher, washing machine, and the oil filled heater in the baby's room to see what a cycle costs on the first two, and what my per-night cost to separately heat the nursery are. May encourage me to fill the washers before use. I'm also 'saving' about $50 a month by setting my thermostat back to 65 at night...if i'm using more than $50 a month heating the nursery, then i'm better off leaving the heat on all the time and scuttling the oil filled heater. Last, its going on the furnace so I can see what the cost of running the blower fan full time is.

So bottom line, I did find a few culprits that used more juice than I thought, even when not in use, and I found some things that I had concerns about used very little or no power at all!
 
I read a post from T-Al on the Simple Living Forum a while back about his phantom load findings in his house. Interesting stuff.
 
Your findings are pretty interesting.  I figured my Directv-Tivo DVR used a lot more than you found.

I'd really be interested in knowing what the washer and dishwasher use to run.  I hope you'll post what you find.
I have an oil filled heater with 2 different watt choices, and always use the lower watt choice.  If your heater has choices also, I'd be interested in knowing whether they actually pull the wattage they list.

How much did that kill-a-watt cost?  
 
Interesting stuff. I would like to hear more, also.
 
It was ~thirty bucks on amazon. I originally bought the lacrosse power controller from them but it arrived doa and they said they had no more to sell. Which isnt stopping them from still showing it on their web site.

The heater wattage rates should be on the unit or in the manual, I have mine. What that controls is how hot the element gets inside. Conceivably, there should be no long term difference in cost between the low and high setting although the unit itself will not get as hot on the lower setting.

What'll be interesting is seeing what the per-night kwh usage is though. Its a small room, I'm expecting it to not be a lot. We'll see.

My dishwasher is a brand new energy star model, but it seems to run a very long time cycle-wise, although i'm using its heated water and 'sani rinse' option as we're washing baby bottle parts in it. The washing machine is a kenmore front loader thats also energy star rated.

Cuberat...looked for t-al's posting on that forum, but you cant search anything without being registered. I registered but 20 minutes later i'm still waiting for the email to complete the registration. :( If you can find and cross post the info here, that would probably be useful to some.

PS...I miss your giant hooters.
 
() said:
Cuberat...looked for t-al's posting on that forum, but you cant search anything without being registered.  I registered but 20 minutes later i'm still waiting for the email to complete the registration. :(  If you can find and cross post the info here, that would probably be useful to some.

PS...I miss your giant hooters.

Registering on the Simple Living site was challenging to say the least.  At the risk of getting my hand spanked by Martha, here's the link to T-Al's post:

http://www.simpleliving.net/forums/simpleliving/topic.asp?
TOPIC_ID=27984&SearchTerms=Trombone

Evidently, I can't post a link in the right fashion. Look in the tightwad forum and do a search on Trombone.

Sorry you miss the hooters.  It was time to put boob woman to rest.   8)
 
Year ago I checked on the main electricity costs in my last house - Mine were electric resistance heating and the continuous furnace fan - The furnace fan is typically a 1/4 hp motor driving a big squirrel cage fan - about 200watts - if used continuously you can add up a lot of KW-Hrs to your bill - it was about half of my summer (no airconditioning used typically) power usage- maybe $20 a month!   :-\

Recently we got a bunch of the R-30 fluorescent lights and replaced most all of our canister lights in the ceilings - before we typically had all the canister recessed lights going much of the day in the kitchen - maybe 600-800 watts - none of the kids or the DW seemed to ever turn off those lights when they left the kitchen - all were replaced there with the brighter 14w fluorescents and I don't ever mind when they're left on - Haven't been able to correlate yet the overall kw-hr savings yet since they have only been installed for a month now.  By the way Home Depot has had a nationwide "Instant Rebate" on multi-packs of fluorescents that ends on Jan 1.   :)

JohnP
 
I miss the hooters dearly. They were a great distraction from my electric bill.

Rat with hooters on its head? Its plausible.

JohnP...yeah, I ran the furnace fan full time for one month last year and very much regretted it when the bill came.

Costco and Sams Club have incredible deals on fluorescent bulbs. I replaced almost all of mine throughout the house. Only ones I cant find cheap are the fancy globe ones for the bathroom vanity. Sams had them two years ago and I bought a set for one bathroom, but now all I can find are $10 a pop at the regular stores.

I've also become the old dad walking around the house turning off lights and yelling 'who touched this thermostat?!!?" I plan to start wearing my pants hiked higher and higher and yelling at the neighborhood kids to get the hell off my lawn.
 
I love my Kill-a-watt! I don't know if there was anything truely useful that I learned from it, but it satisfies my curiosity all the time. One thing I learned was that my chest freezer is running $3-4 a month. We still use it, but I'm wondering if it's worthwhile, or if a new one might be cheaper enough to pay for itself. I also tested all my electronics and was surprized that things like my VCR run 35 watts when "on" (but not playing or recording), and 15 when "off" even though it isn't doing a thing. I was also surprized that my sterio ran at the same power if it was just "on" but not playing as it did if it was playing at full volume. That one I really don't understand. It's interesting about your computer -- mine went down to 2w in "sleep" mode (probably different from the "standby" mode you're talking about). My space heater in the baby's room runs a little under 2kwh a night, and it's taking the room from about 65 to 69.
 
Finally got into the simple living forum. Turns out I dont know my own email address and had to reregister. Got to the thread you highlit above by cutting and pasting both parts.

Here's the salient piece of Al's post...
I found that I was using about 161 watts even when everything was off. At the marginal rate of .17625 per KWH, this corresponds to $249 per year. With some experimenting and my Kill-a-watt meter I determined what was contributing to this load. This is what I found:

Device Power Cost/Month Cost/Year
DVR 30 3.81 46.32
TV 4 0.51 6.18
Ans Mach 1 0.13 1.54
Ans Mach 5 0.63 7.72
Chargers 3 0.38 4.63
Printer 9 1.14 13.9
Comp Speakers 3 0.38 4.63
UPS 7 0.89 10.81
Router (on) 2 0.25 3.09
Cable Modem (on) 12 1.52 18.53
Microwave 7 0.89 10.81
Nightlights 10 1.27 15.44
Clock Radios 5 0.63 7.72
Water Heater 7 0.89 10.81
Stove 10 1.27 15.44
Telephone 2 0.25 3.09
Cordless phone 2 0.25 3.09
Cordless phone 2 0.25 3.09
Laptop (chrging) 40 5.08 61.76

Total 161 $20.43 $248.58
 
Bongo...my tower for some reason still runs its power supply fan while in XP's 'standby'. Some machines will be better at sleeping or standing by than others.

I didnt build this one for low power... ;)

I did have a little cube I used to use with an ultralow power CPU and a small little power supply...that whole thing only ran about 70 watts in use. Unfortunately its proprietary internal power supply died and a replacement cost more than the box. I did end up getting a regular small atx supply, cutting a hole in the sheet metal on top of the case and screwing the PS to the outside of the case with the fan poking into the case. Definitely not something you want to leave around an 11 month old, but it looked pretty cool. I called it the "hemi computer".
 
One thing I learned was that my chest freezer is running $3-4 a month.  We still use it, but I'm wondering if it's worthwhile, or if a new one might be cheaper enough to pay for itself.

I posted this question on the Simply Living Forums a few days ago but didnt think of somthing like this. Have you checked into new models.

http://www.ajmadison.com/ajmadison/itemdocs/AFC2207BW_EG.pdf

this energy star unit notes $42/yr
 
Here's my post on this topic on another forum. 

The Kill-a-watt is tons of fun (mine was $28 on Ebay). 

The fan for our furnace takes 500 watts!  I had been using it to distribute heat from the fireplace.

We've reduced our electric bill from $60 to $40 per month by turning off the computer more and some other things. 

Rough rule of thumb: If it's on all the time, multiply the wattage by 1.5 to get the yearly cost in dollars.
 
And if you don't have a Kill-a-watt, here's what you can do:

1. Go to the meter and use your watch to measure how many seconds it takes for the horizontal disk to make one revolution.

2. If there is a "7.2 KH" somewhere on your meter, divide 25,920 by the number of seconds you measured to get the current power usage in watts.

For example, if it take 60 seconds for the disk to go around once, you are currently using 25,920/60 = 432.0 Watts.

If there is a "3.6 KH" on your meter, divide 12,960 by the number seconds you measured to get the current power usage in watts.

--------------------------------

Here's how I calculated this, perhaps someone can check my math.

I called the power company and asked how many KWH's (Kilowatt-hours) are indicated by one revolution of the disk. Their answer: "Divide 1000 by the KH rating on the meter to get the Revolutions per KWH". So, for my 7.2 KH meter that corresponds to 1000/7.2 = 138.889 revolutions per KWH.

That corresponds to 1/138.889 = .0072 KWH/revolution
Multiply that by 60 to get 432 Watt-Minutes/Revolution
Multiply that by 60 to get 25,920 Watt-Seconds/Revolution

To get the wattage, divide 25,920 Watt-seconds/Revolution by seconds/Revolution. The seconds and revolutions cancel out, and you get your answer in watts.
 
maddythebeagle said:
I posted this question on the Simply Living Forums a few days ago but didnt think of somthing like this. Have you checked into new models.

http://www.ajmadison.com/ajmadison/itemdocs/AFC2207BW_EG.pdf

this energy star unit notes $42/yr

Slightly off topic, but I noticed your AJMadison link and a shudder passed through my body. I had the worst buying experience of my life dealing with this on line scam business. I don't want to re-live the experience by describing it again, but I would recommend an alternative to anyone who is thinking about purchasing from the thieving b*stards them: take whatever cash you were going to send AJMadison, open your front door and toss it out. It will save you time and aggravation and the end result will be the same. :rant:

Take a look at their record on epinions.com if you want to see other horror stories....
 
Bought a large LCD HDTV just to save electricity. Does replacing all one's CRT TVs save more electricity than replacing incandescent light bulbs with fluorescent ones?
 
I wish you guys had talked about this a couple weeks ago, it would have made a PERFECT gift for my dad, humm I'll have to remember this for his birthday.
 
Buy one now and mark it on your calendar on his birthday, that you bought him a gift already.
It's a great gift idea.
 
Well I have bad news on the fancy dan new tv department.

My brand new JVC 55" LCoS set uses about 180w, with surging up over 200W. The brand new 65" toshiba high def CRT set I bought a few months ago runs about 140W. My 10 year old Maggotbox uses about 150W. I thought maybe a true LCD set instead of a microdisplay projection set would use less, but I see Sharps Aquos 45" set is manufaturer rated at 300W.

I had figured the huge CRT set as the biggest pig and the new microdisplay set as the energy sipper...wrong again...

So a few more tidbits...my new kenmore energy star dishwasher costs about 28c a load to do the dishes, with every option turned on...smart wash, heated water, sani-rinse, and heated drying. So about eight bucks and change a month to use. Hmm...if I had 4-5 pots to wash I'd just do them by hand to save running an extra load of dishes. For 28c I think i'll run them through the dang dishwasher from now on.

Next two long term tests are the washing machine and the nursery's electric heater.

I'm guessing at this point though that my standard non-heat, non-AC $110 electric bill is ~10 dishes, ~20-25 clothes washing, ~15-20 'phantom loads', and the rest is lights, televisions, coffee makers and the like in regular operation.

Good to know what does what...some presumed good actors werent, some surprising bad actors have popped up, and with a few very minor changes I can save myself $30-40 a year.

More when I have it...
 
Coffee pot (bog standard mr. coffee) to brew 12 cups and keep it hot for 2 hours, about .30kwh, or a little under 10c.

I was shutting it off after an hour if I wasnt going to have another cup immediately and then warming one in the microwave if I wanted it. Bet the minute in the microwave costs more than the extra hour of burner time... :p
 
Get a coffee maker with an insulated carafe; keeps warm all by itself...
 
() said:
Next two long term tests are the washing machine and the nursery's electric heater.
Good luck with that-- you'll have to let me know how it turns out.  "But Dad, if you want me to do less laundry then you'll have to spend more money on my clothing budget!"

I'm planning to use my new toy tool to meter our kid's energy waste.  (Perhaps it's easier & cheaper to put timers on the hallway light switch, but nowhere near as much fun.)  I bet our CRT TVs and six VCRs add up to a hefty phantom load, too.  

I'm also hoping to settle the discussion on the garage's ultrasonic anti-rodent gizmo.  I think it's a waste of energy while spouse claims that it keeps away landsharks & white elephants as well...

TromboneAl said:
And if you don't have a Kill-a-watt, here's what you can do:
I was wondering how to handle 240V appliances.  Our electric clothes dryer puts a pretty impressive spin on the meter but there's substantial family resistance to hanging wet laundry in the garage.  Maybe I should claim that the ultrasonic gizmo speeds the process.

TromboneAl said:
Here's how I calculated this, perhaps someone can check my math.
Yep, the power company is telling you that there's 7.2 KWHr/1000 revolutions.

(7.2 KWHr/1000 rev) x (3600 sec/Hr) x (1000 watt/KW) = 25920 watt-sec/rev

(25920 watt-sec/rev) / (# sec/rev) = watts

() said:
Bet the minute in the microwave costs more than the extra hour of burner time... :p
Generally a microwave oven is a more efficient water-heating tool than a heating plate or a stove burner, although microwaves are a bigger capital investment. But now we have the tools to validate the theory!
 
Back
Top Bottom