Any way to measure electricity use by 110 appliances?

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So, newer appliances are supposed to use less electricity. Anyone know whether there is a device one can use to actually monitor how much each appliance is using?

Also, we have a Nu-Tone instant hot water device by sink. Is it cost effective? (Hot water tank is a long way, downstairs in fact, from kitchen.)

-- HV (veggie@ourplace.com), January 24, 2002

Answers

Your utility should have a gadget that you can borrow or rent to do this--you plug the item in the gadget, and the gadget into the socket I think. The name of it escapes me at the moment.

-- GT (nospam@nospam.com), January 24, 2002.

You can tell how much power its using two ways. One look on the label. It should tell you how many watts it is using. Second way is to put a current (amp) meter inline with the device. Multiply the voltage your measure x the current for the power in watts, 120v x 10 amps is 1200watts or 1.2kw.

-- Gary (gws@columbus.rr.com), January 24, 2002.

Our utility in Clark County, WA loans the time of meter suggested in the first answering post. Perhaps others do as well.

-- Dianne Wood (woodgoat@pacifier.com), January 24, 2002.

Ask your utility for a "test meter" for appliances, one that has the matching plug to plug in your appliance. If it is direct wired, they can also assist you in this endeavor. Run the appliance for an extended period of time...say 30 days to get an accurate usage. Don't forget seasons also will vary temperature sensitive equipment.

There should be no charge for this service.

Taking the wattage of an appliance and doing the math on an appliance that is controlled by a thermostat will not provide you a correct answer. You need to actually measure the usage under your operating conditions. Those tags that provide you with comprable usage are sales gimmicks and only comparisions under test conditions.

On the instant hot water tank supply, these are usually located near the faucet using the hot water. The shorter the run of pipe the less losses you will experience. I do not find these economical however people sware they work for them. Mainly, you have a small tank (2 gal) and a very high wattage element (9 KW) or (9000 watts).

A regular 30, 40 or 52 gallon electric water heater has a 4500 watt element on top and another 4500 watt element on bottom. The top element only runs when you have exhausted the hot water in the tank. The bottom element runs to maintain the tank at set temperature. Both elements will not operate at the same time. There is a way to hook up both elements where they will opeate at the same time; however, most utilites have specific residential rates that do not allow this. The reason for that is you double the demand on the electric system in the area and if every one with an electric water heater did that, the utility would have to install larger transformers to provide service to you or a group of customers. And the tarriffs are designed on a cost of service reflecting the single 4500 watt element element operating.

An alternative to the under counter water heater would be to install a low boy 30 gal water heater under the counter near the most used areas. Typically the most used water area is the kitchen, followed by the laundry room.

Hope this helps! As this comes from studies performed over the years with a utility company.

-- milam gerick (milamgerick@juno.com), January 24, 2002.


I'm trying to get some information from my electric company right now. My bill usually runs $75 each month (I growl about that!) but last month was $165!! EEP! ERK! Financial RUIN!! So I've contacted my cable company to come out and assess my usage. My house was built in '57 so it doesn't have any grounded wire. I suspect that I am leaching power out somewhere. I know that my two tank heaters (one for the horses and one for the extra goat/chicken/rabbit/geese/duck/guinea/dog water) is running it up. But WOW! I had the person check and she said it has historically run higher for me those months. I suspect heaters. But it will be nice to get some more info from them.

-- Gailann Schrader (gtschrader@aol.com), January 24, 2002.


Gailann, They probably misread your meter. This has happened to us before. The bill will tell the day they read the meter. When you get the bill, usually only a few days have passed. You can still go out and read the meter -- it will only have changed a little. If it is not close, call and ask them to re=read you meter. My electric was read wrong 2 months in a row-only time in 18 years. We had a good laugh about it with the customer service rep.. Maybe a new meter reader.

-- connie in nm (karrelandconnie@msn.com), January 24, 2002.

Yes there is its ----Digital Power Meter--you can measure watts & watt-hours. It's good- it works very well.-Brand Electronics-1-888-433-6600--www.brandelectronics.com

Several models starting at $150......not cheap...but their good!.

-- Jim-mi (hartalteng@voyager.net), January 24, 2002.


Brand Electronics----Digital Power Meter----1-888-433-6600---www.brandelectronics.com----measures watts & watt-hours etc. etc. Starting at $150 ----not cheap, but works good!!!

-- Jim-mi (hartalteng@voyager.net), January 24, 2002.

If you have a digital multimeter, you can calculate the value using the power formula P=VI.

-- Jay Blair in N. AL (jayblair678@yahoo.com), January 24, 2002.

We here at the Alternative Energy Store also sell the Brand Meter mentioned above for $134.55 and $152.49 for the 1850W and 3700W version, respectively. I have been using the 1850W one for 3 months now solely for curiosity's sake - to see if the Energy Star rating is correct. So far, my Whirlpool fridge actually appeared to consume less KWHr's - according to the running average that the meter has kept so far. My next step is to test our washer and see if I can justify buying the ultra-efficient Staber washer for our home.

Here are the links for the two brand meters on the Alt-E Store's online shop:

Brand Power Meter 1850W 115VAC http://www.AltEnergyStore.com/cart/195.html

Brand Power Meter 3700W: http://www.AltEnergyStore.com/cart/196.html

Kind Wishes - Sascha

-- Sascha Deri (sascha.deri@altenergystore.com), January 25, 2002.



You mention two electric heaters for water...horse and goats.

What is the wattage of each? and how long do they run...are they on all the time?

For example: 2- 750watt heaters left running for 1 month and assuming the water temp is set so they operate all the time:

750watts x 2 htrs = 1500 watts or 1.5 KW 1.5kw x 720 hrs per month = 1080 kwh @ 10 cents per kwh = $108

You need to check is you can set the temperature at proper temp without having freezing problem to save on $$$.

The other item mentioned is the ground. I assume you mean no ground indoors at the outlets. By all means you should have a ground rod outside with a ground wire to the box and equipment for safety purposes.

Hope this helps...

-- milam gerick (milamgerick@junoc.om), January 25, 2002.


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