Energy conservation

[gar]

090402-1721 EST

Last night I installed the "TED" power monitor at my home. I am done with bench testing for now.

I really do not like the small thinly insulated wires that come from the current transformers. Mechanically I do not like their use in a main panel. Too easy to damage. Because I have 0000 wire into the main panel I had some difficulty in getting the transformers installed. There is no bending those wires.

I was running a residual load around 360 W last night, but it was necessary to turn some things off to get to this level. Prior to removing some load I was around 500 W.

Today I have run in the range of 1 to 2 KW. But I have kept some items off that normally I would leave on. From 1015 this morning to 1711 this afternoon, almost 7 hours, the DTE Energy reading changed from 10808.2 to 10819.0 and the TED reading changed from 9.6 to 19.9. The differences were 10.8 and 10.3. I had peaks greater than 2 and mins less than 1. 10.3/7 = 1.47 for an average KW load or 1.47 KWH average.

Their data logging software is called "Footprints". I do not care for their design, and I believe the graphing and printing parts have bugs.

Their live "Dashboard" showed a peak voltage of 127.2 V at 0155. There was no data recorded until
"2009-04-02 05:59:23","1.07","0","122.7" .
They showed a minimum voltage of 113.4 V at 1408. There was no data recorded at 1408. There was a gap of data between
"2009-04-02 13:56:57","1.53","0","123"
"2009-04-02 15:53:34","1.75","0","122.2"
because I was collecting on a different computer.

Using their program to export data from their *.db database file to a *.cvs file I got the above information.

On one computer I can not get data plotted from the database even though on that computer it puts data into the database.

I have errors on trying to print their manual for the software. They do not provide a printed copy. However, for the most part the manual does not solve my problems. Also I get errors on trying to print the graph. There needs to be great improvement in their software.

.

 

[gar]

090402-2000 EST

Looking at voltage thru the day it was generally in the range of 123-124 V from about 0700 EDT to 1945 EDT and gradually dropped to about 121 by 2015 EDT, and now at 2100 EDT it is about 122.5 .

.

 

[glene77is]

We've got something similar on top of our telly and its just brilliant. ...

Buckley,

On the website, the demo 'flash' screen was very dramatic.
IF GAR saw the demo page, :smile:
THEN he would switch from 300 W tube monitors to the 50 W LCD monitors.

It is obvious that with this reminder of Current Wattage Used
any person could save enough (10%) to pay for it.
The green feeling would be great.
I have a customer who did the simple switch,
where I replaced ALL the incandescent light bulbs with CFL's.
Next I will put LED twinkle lights in her "socializing garden" trees.
I don't know if they will save enough to pay the switch-over costs,
not in the first year at least,
but as they said "The Green Feeling is Great!" :smile:

 

[SAC]

Thanks gar - from what you say it isn't perfect but it looks like it does enough to be worthwhile to me. I also poked around on the web, and people have even reverse engineered the power line protocol and the usb protocol, and written their own data collectors to bypass the footprints software. Not sure that's a project that I'd like to take on, but there seems to be enough interested out there that maybe someone will do a shareware app that is better than the footprints software - or maybe footprints will be improved over time.

 

[glene77is]

Quote\
"Last week I order one of the "TED" units, and it arrived today."
\Quote

Gar,
You are an experimentors dream !

 

[glene77is]

Quote\
"Last week I order one of the "TED" units, and it arrived today."
\Quote

Gar,
You are an experimenters dream !

The following is "IMO" as an older student.
It is intended only to show what I perceive as a different perspective
on the same subject, Power, as seen from Electrical and Electronic.

Regarding 'why' an ET would think the power could be RMS,
I enclose a circuit I designed some years back, as an "ET".
Note that Electrical methods and Electronic analog design methods
have some different approaches to the same subject.
IF, all real world electrical values are occurring at an "Instant",
Then they are ,only, 'peak' values, and nothing more.

In ET, the approach is to sample the stream of instantaneous values.
The typical method of obtaining an RMS voltage value
from an input signal (of real world 'peak' values),
is to calculate the Mean, then apply the anti-log controls.
Using a similar approach from a CT (coil pickup) for current,
we then have two RMS values, which could be logged, and summed.
To some, it would seem OK to name the final result
to be an "RMS" result.
Since we are referring to Power,
Then the 'erroneous' term "RMS power" might come up.

I hope the attached circuit helps in showing the ET approach.

 

[gar]

090403-2056 EST

glene:

Do you have any curves or data showing how well your circuit performed?

There should be no difference in the definition of RMS whether applied to mechanical measurements, such as surface finish measurement, electrical of any kind, pneumatic, or anything else.

It appears that the Federal Trade Commission and lawyers is where the incorrect use was originated.

No matter what is measured RMS is going to mean the square root of the average value of the integral of a variable squared. The integral evaluated over a range and divided by that range produces the average value. You either do this over a large number of cycles, or an integral number of cycles.


Tonight I have seen the supply voltage gradually drop from about 124 V to 122 V over a 2 hour period from 1845 EDT to 2030 EDT. It generally was around 124 V throughout the day. This change was a rather uniform slope. This probably implies the gradual increase in load as darkness developed and dinner was cooking. This was not caused by my loads, and/or my neighbor. This originated from the grid. And now the voltage has gradually risen over about 1.0 hour to near 123 V.

My 120 V 1.5 KW heater test load produces a voltage drop of about 0.5 V at the main panel as seen by TED.

I had some very erroneous power readings at two points this afternoon. One was exactly 51.78 KW for 2 minutes and 47 seconds. When these power errors occurred there was no corresponding change in the voltage. 52 KW would have produced many volts drop.

There are also times when TED gets no data for a moderate period of time. Meaning many seconds or maybe as long as a minute. I think it would be much better to transfer data by wire rather than carrier current.


SAC:

Based on you poking around comment I did some and it appears that others also find fault with the TED Footprints software. It is useful to have something that allows data collection and plotting, but something much better is needed.

.

 

[gar]

090404-1158 EST

For 2-10-09 thru 3-12-09 my total KWH used were 1311 for a daily average of 43.7. This is from the electric bill.

For the day 4-3-09 my total usage was about 36 KWH based on TED's reading. I had kept some equipment off that would normally be on. If I could consistently reduce usage by 7 KWH/day, then this is 365*7 = 2555 KWH/year. My current cost is $0.127/KWH. Thus, 7 KWH saving per day is $324/year,

Our electric rates are expected to go up about 15% fairly soon.

This morning from midnight to 0647 EST I consumed 7.4 KWH, or an average of 1.1 KWH. From 0647 to 1315 the consumption was 15.0-7.4 = 7.6 KWH or 1.18 KWH average.

From watching the data I find that the furnace blower motor is on most of the time, and our outside temperature was in the range of 30 to 40 deg. F. This motor uses about 400 W. Would the house be as comfortable if the duty cycle was lower? I do not know.

Today I have had another erroneous reading. This time it is exactly 18.33 KW for 2 minutes at 0815:13. Clearly there is a hardware, software, or communication problem. It is clear measurements were being received once each second, or at least the program thought so. One really needs to know what is the actual data from the carrier current signal to identify the problem.


The April 2009 Fortune Small Business publication had an article on Tendril. I truely do not understand what they are making or selling. One would conclude they make some sort of power monitors, but their site is un-understandable. See www.tendrilinc.com .

.

 

[gar]

090728-0811 EST

I am continuing to use the TED monitor. There are times when I can hold my total usage per day down to about 30 KWH.

Now I am starting some new experiments using the "Kill A Watt" meter. I have an upright Admiral freezer that we purchased used from the local recycle facility in town. It works very well, even in 0 degree weather in the garage.

The temperature setting is such that it cools to approximately 1 degrees and warms to about 6 degrees before cooling starts again. Both cooling and warming are long time constants. This freezer is currently relatively full.

The thermistor temperature sensor gaging element is near the freezer top placed between some packages of food. The hysteresis of 5 degrees is at the thermistor location, and may be somewhat larger at the freezer thermostat. In the future I should setup a pair of thermocouples to measure the difference between ambient and internal temperature.

The outside box of the freezer is 30" wide, 27" front face of door to rear, and 61" high on front face of door. This is a total outside surface area of 3660 + 3294 + 1620 = 8574 square inches, or 59.54 square feet. This is approximately the heat loss surface area.

Some limited results are:

Date-Time Ambient Int   Voltage Amperes Power  VAmp   PF   KWH    Time  Ave Power
          Temp    Temp 

090727
  -1410     76           122.4            29               0.00   0.00
  -1416     76           120.5           277    409  0.66    
  -1430     77           122.2           263    414  0.63  0.09   0.33     270
  -1508                  122.3    3.30   250    404  0.61  0.25   1.00     250
                   4     122.5            29     30  0.98     
  -1735     80     4     121.8    3.39   266    413  0.64  0.52   3.47     150
  -2000     80     2     124.9    0.24    30     30  0.99  1.06   5.85     181
  -2130     80     6                     374    500  0.74  1.11   7.37     151

090728
  -0742     70     2     123.9    0.24    30     30  0.99  2.97  17.57     169
  -0815     70     3     124.6    0.24    30     30  0.99  2.99  18.12     165
  -0837     70     4     124.8    0.24    30     30  0.99  3.00  18.48     162
  -0851     70     4     124.4    0.24    30     30  0.99  3.01  18.70     161
  -0927     70     6     122.7    3.64   307    447  0.68  3.10  19.32     160

Some observations. This is a limited test to get a feel for how to run the experiment. The above tests were essentially without opening the freezer door except near the beginning of the test run.

An approximation of my yearly cost is 0.160*365*24*0.13 = $182.

I noticed that when the compressor first turns on that power input is greater and this gradually decreases over many minutes. At -2130 I got a reading very close to when the compressor was turned on. At -0927 it had been on for a short time. At -1508 it was probably near the end of a cooling cycle.

With no cooling it appears the temperature rate of rise is about 3 degree per hour. Note: the rise of temperature curve is an exponential curve like an RC curve.

.

 

[sgunsel]

Gar,

Looks useful to me. Are the CTs clamp on?
I can't seem to locate for less than $120, quite a bit above $80. Sources?

Thanks.

 

[gar]

090728-1936 EST

sgunsel:

The current transformers are clamp on and about a 1" hole.

I believe there is no price of $80 for the TED 1001 new. The basic unit plus software is about $180 and you can probably save that much in less than a year if you make good use of the information. You can not build the product yourself for that kind of money.

At the moment I have a 1.55 KW load. That is close to my daily average at the present time. If I make an effort I can get down to about 30 KWH per day.

If you play with the TED device you can add to your broad base of background knowledge. I would also suggest that you get two "Kill A Volt" P4400 meters.

I just turned off the kitchen and some shop lights and the load is 1.04 KW.

.

 

[gar]

090728-1959 EST

Some additions to my freezer chart.

Date-Time Ambient Int   Voltage Amperes Power  VAmp   PF   KWH    Time  Ave Power
          Temp    Temp 

090727
  -1410     76           122.4            29               0.00   0.00
  -1416     76           120.5           277    409  0.66    
  -1430     77           122.2           263    414  0.63  0.09   0.33     270
  -1508                  122.3    3.30   250    404  0.61  0.25   1.00     250
                   4     122.5            29     30  0.98     
  -1735     80     4     121.8    3.39   266    413  0.64  0.52   3.47     150
  -2000     80     2     124.9    0.24    30     30  0.99  1.06   5.85     181
  -2130     80     6                     374    500  0.74  1.11   7.37     151

090728
  -0742     70     2     123.9    0.24    30     30  0.99  2.97  17.57     169
  -0815     70     3     124.6    0.24    30     30  0.99  2.99  18.12     165
  -0837     70     4     124.8    0.24    30     30  0.99  3.00  18.48     162
  -0851     70     4     124,4    0.24    30     30  0.99  3.01  18.70     161
  -0927     70     6     122.7    3.64   307    447  0.68  3.10  19.32     160

  -0949     70     4     122.6    3.40   270    417  0.64  3.20  19.67     162
  -1010     70     3     123.6    3.39   261    418  0.62  3.29  20.02     164
  -1037     70     2     123.1    3.35   257    370  0.62  3.41  20.48     167
  -1151     74     3     124.6    0.24    30     30  0.99  3.56  21.70     164
  -2030     78     4     125.4    0.24    30     30  1.00  5.00  30.38     165

Thus, 164 W average power consumption looks to be a good value for the current ambient air temperature.

.

 

[76nemo]

Seen these?

Seen these?

http://www.bluelineinnovations.com/default.asp?mn=1.274.285.388


We used to work on those. For $160, they took off well.

 

[weressl]

http://www.bluelineinnovations.com/default.asp?mn=1.274.285.388


We used to work on those. For $160, they took off well.

So let me understand this. These are units that tell me that I am using too much electricity?

Uhmmmmm........ who turned on those devices in the first place?

So is it like the adult version of "turn off the light when you leave the room" admonishment? If you haven't learned when you were a kid, now they SELL you a gizmo that tell you what you weren't able to learn while you were a kid?

Duh........

Or am I missing something here?

 

[gar]

090729-1020 EST

Having instruments that can provide reasonably accurate quantitative data and intelligently used can have a substantial impact on energy usage.

As an example, as I started to respond here, I noticed that my TED indicator was at about 2.5 KW. This seemed high. First guess was that my wife left the dressing room lights on. It is two flights up from the basement where I am. Yes they were on. Also I had left some work area lights on that I really do not need at the moment. Turned these off and I am at 1.15 KW. Major items on at the moment --- 1 refrigerator, 1 freezer (not the one from which I am collecting data), and my computer.

On the freezer I am currently testing the on period is about 44% (164/370) of the total cycle time. An experiment I will run later will be with about 4" of foam insulation around the outside of the cabinet. This experiment should show a substantial change.

Assuming no air leakage the heat loss from an enclosure in still air is a function of the outside surface area and the thermal resistance to the interior. The thermal resistance is determined by the insulation between the outside surface and the interior. A typical calculus question is what rectangular shape box has the least surface area to interior volume? This shape is a cube.

I looked at the discussion on the Power Cost Monitor mentioned by 76nemo and it looks less useful than the TED unit. The computer logging capability of the TED unit is very useful.

For monitoring a single device the Kill A Watt 4400 is a very useful instrument for the money. Aside from its power monitoring it can be used as a voltmeter to look for high resistance joints in branch circuits, including neutral problems. Its resolution is 0.1 V.

.

 

[Doug S.]

So let me understand this. These are units that tell me that I am using too much electricity?

Uhmmmmm........ who turned on those devices in the first place?

So is it like the adult version of "turn off the light when you leave the room" admonishment? If you haven't learned when you were a kid, now they SELL you a gizmo that tell you what you weren't able to learn while you were a kid?

Duh........

Or am I missing something here?

Actually I think you are on to something. Are any of the fine people that did voices for Hanna Barbara still alive? I bet a plug in device that has Fred Flintstone yell TUURRNN OOOUUTTT THOOOSE LIIIIGHTS! would sell at a decent margin. :smile:

Doug S.

 

[bpk]

These things remind me of those mpg units that some vehicles have. It seems like useless information but now when times are tight I have started to watch mine a lot more and been less likely to step on it when takeing off from a stop light. I bet some homeowners have no idea of what certain appliances and other loads cost to run. Just lately my wife was running the clothes dryer with 1 shirt in it, she has no idea that its equivelant to about 80 60 watt light bulbs.

 

[Mike01]

Meter Reading

Meter Reading

Just curious how to you read / caculate from a standard meter?

 

[Jraef]

These things remind me of those mpg units that some vehicles have. It seems like useless information but now when times are tight I have started to watch mine a lot more and been less likely to step on it when takeing off from a stop light. I bet some homeowners have no idea of what certain appliances and other loads cost to run. Just lately my wife was running the clothes dryer with 1 shirt in it, she has no idea that its equivelant to about 80 60 watt light bulbs.

I have similar arguments with my wife. She gets on me for leaving a 9W CFL burning in my workshop as a night light because I hate going in there with my hands full and fumbling around for the light switch. Then she leaves the TV on for hours when she isn't in the room because "she likes the background noise". I have made the argument that a 1500W TV running for 3 extra hours per day for a week is still worse than my 9W CFL running 24/7 or 3 months. She just doesn't get it. She is "logic challenged".

 

[gar]

090730-1121 EST

Mike01:

What is a standard meter? Are you referring to the KWH meter on the side of your house? To a Simpson 260? A Fluke 87? A Weston or Simpson wattmeter?

I will point out that the neat little trademark product "Kill A Watt" meter reads --- V, I, W, VA, Freq, PF, KWH, T since last reset. Its voltmeter works fairly well from 110 to 130. Accuracy starts to fail below about 110 and is useless by 102 to 105. This voltage range is potentially a serious limitation.

What is your present class level? What courses have you had? Any instrumentation courses?

.