Bunn Coffee Maker & Kill-A-Watt

mbkerk · May 16, 2008

I "won" one of these from my electric cooperative a few months back.

Since then I have been playing around with it, experimenting on what it costs to operate different appliances in my home. The "Kill-A-Watt" keeps track of total KWH's used by whatever is plugged into it, for as long as the appliance is plugged into it. It also monitors voltage, frequency, real time load in amps or watts, as well as volt/amps and power factor. I don't even know what a VA or PF mean. (someone please explain!)

Anyway... most recently I had the device hooked up to my Bunn coffee maker. As fellow Bunn owners know, the coffee maker is never turned off. It runs 24/7 keeping water hot for your next cup of coffee. It makes a full pot in about 3 minutes.

Here are my findings for energy usage for the Bunn for a month. I make at least 1 pot of coffee a day. We also use it from time to time to make hot water for cappuccino mixes, soups, etc. I tried to use it use it just as I would have in a "normal" month. Plug in your own cost's per KWH, and you should get a rough idea what you are using.

Total time of test= 731 hours (30.45 days)
Total KWH usage= 28.46 KWH
28.46 X .085/KWH= $2.42 for the month.

I expected a lot worse!

The Bunn has a small heater running all of the time. It uses 30 Watts 24/7 regardless if it is in use or not. When the water gets too cold, the big heater will cycle. That heater is about a 700 watt heater (seems to vary) and will come on when adding water or a few times a day to "catch up". Then there is the warming plate, 130 watts, that is seldom used in our house. Most of the time I make coffee, it is in the thermos bottle and out the door!

Currently I have the Kill-A-Watt hooked up to my Mac Mini computer and all of the peripherals (printer, speakers, monitor, etc.) The computer never gets shut off, though does go to "sleep" when not in use. I will let you know in another 25 days or so what I find!

Ingersoll444 · May 16, 2008

Thats a cool little meter!!

Where can you get them from?

mbkerk · May 16, 2008

Ingersoll444 said:
Thats a cool little meter!!

Where can you get them from?

Google it Paul... they are all over the place. Harbor Freight sells them, eBay, Amazon... They cost about $25. I won it by submitting an energy saving idea to my electric coop. I say "won" because they forgot about the contest for a year, and when I didn't see any other entries in the monthly magazine they send out, I "reminded" them, and then told them what I wanted for a prize! Got it in the mail a few days later!

grapeknutz · May 16, 2008

http://www.newegg.com/Product/Product.aspx?Item=N82E16882715001

Ingersoll444 · May 16, 2008

Cool. I will check it out! Thanks

bblalocksr · May 16, 2008

mb as I remember it VA is just Volts times Amps or Watts.

PF is the power factor or effeciency of a machine. If you put in 100 units and you get 50 out in work, the PF would be .5 or 50%.

Hope I explained it right.

jechrist2 · May 16, 2008

Thanks for the report, Mark. A lot of us complain about our electric bill and then we forget about all the "little" things that use electricity all the time.

For example, how many of our electrical appliances have clocks built in? How much electricity does each clock use?

Certainly we all need clocks. If you look around my kitchen at least four clocks are running. The kitchen is only a 12' X 14' room, I really don't need to have that many clocks in one space!

Later,
Jerry Christiansen

Mark / Ohio · May 17, 2008

I'd like to get me one of those meters. Trouble with using my ammeter is it really can be inaccurate as with some things it is hard to know or calculate what the duty cycle is. Anymore most anything that plugs in is on to a certain extent even when it is off. The old mechanical switches are becoming extinct.

1086 · May 17, 2008

I recently used a Kill-A Watt for a 24 hour test on a new refrigerator. According to the meter it will cost $6.00 plus change / month to operate @ 15 cents/KW. The 25 year old fridge that was replaced was costing around 18 bucks/month.

MowHoward2210 · Nov 14, 2008

Mark: Did you ever test the Mac mini?

Larwyn · Nov 14, 2008

mbkerk said:
I "won" one of these from my electric cooperative a few months back.

Since then I have been playing around with it, experimenting on what it costs to operate different appliances in my home. The "Kill-A-Watt" keeps track of total KWH's used by whatever is plugged into it, for as long as the appliance is plugged into it. It also monitors voltage, frequency, real time load in amps or watts, as well as volt/amps and power factor. I don't even know what a VA or PF mean. (someone please explain!)

[/CENTER]

Great little meter and your "test subject" (the Bunn) is an appliance that I was thinking of replacing. I did not realize that it was such a light load on the system. Thanks for the info.

As for VA, it is Volt Amps which is volts times amps. And is equal to watts only if the PF (Power Factor) is equal to 1 (100%). In fact; watts = volts *amps * PF. Technically PF is the Cosign of the angle between the volts and the amps. Some loads will cause the voltage to either lead or lag the current. This angle can be measured and used to calculate the PF. Power Factor can never be higher than 1 and is usually less than 1, so your Volt Amps will actually be higher than your Watts. The rest is known as VAR's, which is equal to the VA times the Sine of the angle between the volts and the amps.

Sorry if this sounds confusing, but believe me, many who work in the electrical transmission and distribution field have problems with understanding the concept of VAR's.

mbkerk · Nov 14, 2008

MowHoward2210 said:
Mark: Did you ever test the Mac mini?

I did... but 1/2 way through the test we had a power outage which reset the Kill-A-Watt! :banghead3

Then I got busy with summer stuff...

I will get it hooked back up to the mini soon and let you know the results!

Larwyn said:
Sorry if this sounds confusing, but believe me, many who work in the electrical transmission and distribution field have problems with understanding the concept of VAR's.

It sure gives me a headache! Sounds like something I don't need to know to wire an outlet! :ROF

Larwyn · Nov 15, 2008

Yep, so far they only charge us for the kilowatts, the VAR's are free. I'm retired, no need to strain my brain on stuff like that..........:trink40: :trink40:

Mark / Ohio · Nov 15, 2008

Maybar said:
I recently used a Kill-A Watt for a 24 hour test on a new refrigerator. According to the meter it will cost $6.00 plus change / month to operate @ 15 cents/KW. The 25 year old fridge that was replaced was costing around 18 bucks/month.

The money saved on electric intern goes to the manufacture purchasing a new refrigerator after the compressor dies with only a fraction of the total operating hours on it as the old one had. :goodl:

c5rulz · Dec 3, 2008

I don't care what it costs, Bunn Coffee makers are the only coffee makers to buy in our househol.:trink40:

Robert M · Jan 8, 2009

c5rulz said:
I don't care what it costs, Bunn Coffee makers are the only coffee makers to buy in our househol.:trink40:

Depends which one you buy, I've wore out countless coffee makers. Including Bunn's. An average day is 4 pots of coffee and I'm the only one here that drinks it.

I managed to lay my hands on a restaurant Bunn a few years ago and so far it's holding up. Got it refurbished from a local outfit that puts coffee makers in a business and then sells them coffee and supplies.Paid $75

Loren012345 · Jan 8, 2009

If you plug a Kill-A-Watt into a Kill-A-Watt how much does it cost to run in the first month? $50? :ROF

Loren

Toolin · Jan 24, 2009

I own a couple of these Kill-A-Watt units.. bought them off eBay some years back on a whim. I think I got them for about $15 apiece. You really can learn some surprising things about your energy usage.

For instance, my tiny little dehumidifier (a common model available at Home Depot, etc) running in summer in the basement sucks a HUGE amount of energy. I think it worked out to about $2/day, and that was running at about 50% duty cycle (2 hrs on, 2 hrs off)

One very annoying thing about them though.. they cover the entire electrical outlet (both sockets) even though it only uses one socket. Using a power strip or short extension cord gets around this but it's still a big design oversight and kind of obnoxious.

mbkerk said:
[...] I don't even know what a VA or PF mean. (someone please explain!)

I think there were already a couple good explanations earlier in this thread, but I thought I'd add my 2c...

PF tends to be more important to your power company than to you... until your total VAR (which increases with low PF) is so bad that the power company starts charging you penalties for being so bad.

Basically if you have a lot of "inductive loads" consuming power (things with coils of wire, like motors and transformers), and if they don't have compensating capacitors attached, your power factor is probably significantly lower than 1. This kind of situation consumes both "real" power (resistive, or "VA") as well as "reactive" power (inductive, or "VAR" - Volts Amps Reactive). The real power moves the wheel on the power meter and you end up paying for it and the power company is happy. However the reactive power doesn't do any real work on your end and so doesn't register on your meter, but it still causes extra current to be circulated through the power lines.

All current flowing through the power lines suffers resistive losses, but those losses hit the power company's bottom line, not yours, since it happens before it reaches your meter. So the more current flowing through the lines which they don't get to charge you for (the "AR" in the VAR), the more unrecoverable losses they suffer.

Large operations which have many inductive loads (like factories) have to watch their Power Factor closely and put things like large capacitors across their motors to offset the inductance because the utility company will charge them big fees if there is too much reactive power (VAR) being drawn.

Ok, probably way more than you wanted to know, but *I* had fun talking about it...

notomow · Jan 24, 2009

Thats pretty cool I always wondered how much juice those bunns used.I've had mine forever I would go nuts waiting fo a cup of coffee if mine ever quite.It's so cool to get up pour the water in and stand a few minutes to get your coffee while your half asleep lol.

Ingersoll444 · Jan 24, 2009

Toolin said:
I own a couple of these Kill-A-Watt units.. bought them off eBay some years back on a whim. I think I got them for about $15 apiece. You really can learn some surprising things about your energy usage.

For instance, my tiny little dehumidifier (a common model available at Home Depot, etc) running in summer in the basement sucks a HUGE amount of energy. I think it worked out to about $2/day, and that was running at about 50% duty cycle (2 hrs on, 2 hrs off)

One very annoying thing about them though.. they cover the entire electrical outlet (both sockets) even though it only uses one socket. Using a power strip or short extension cord gets around this but it's still a big design oversight and kind of obnoxious.

I think there were already a couple good explanations earlier in this thread, but I thought I'd add my 2c...

PF tends to be more important to your power company than to you... until your total VAR (which increases with low PF) is so bad that the power company starts charging you penalties for being so bad.

Basically if you have a lot of "inductive loads" consuming power (things with coils of wire, like motors and transformers), and if they don't have compensating capacitors attached, your power factor is probably significantly lower than 1. This kind of situation consumes both "real" power (resistive, or "VA") as well as "reactive" power (inductive, or "VAR" - Volts Amps Reactive). The real power moves the wheel on the power meter and you end up paying for it and the power company is happy. However the reactive power doesn't do any real work on your end and so doesn't register on your meter, but it still causes extra current to be circulated through the power lines.

All current flowing through the power lines suffers resistive losses, but those losses hit the power company's bottom line, not yours, since it happens before it reaches your meter. So the more current flowing through the lines which they don't get to charge you for (the "AR" in the VAR), the more unrecoverable losses they suffer.

Large operations which have many inductive loads (like factories) have to watch their Power Factor closely and put things like large capacitors across their motors to offset the inductance because the utility company will charge them big fees if there is too much reactive power (VAR) being drawn.

Ok, probably way more than you wanted to know, but *I* had fun talking about it...

:fing32: Great post man!! I have NO IDEA what your talking about, but I will reserch it more!!!! very interesting!

Bunn Coffee Maker & Kill-A-Watt

mbkerk

Ingersoll444

mbkerk

grapeknutz

Ingersoll444

bblalocksr

jechrist2

Mark / Ohio

1086

MowHoward2210

Larwyn

mbkerk

Larwyn

Mark / Ohio

c5rulz

Robert M

Loren012345

Toolin

notomow

Ingersoll444

Top Contributors this Month

Recommended Communities