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Idle power control – phase 2 complete

Posted by admin on Nov 18th, 2008
Nov 18

So phase 2 of the idle power consumption testing is complete, and with some surprising results. It seems that the X10 appliance module didn’t consume hardly any electricity going by the Kill-a-watt numbers. Unfortunately the time measurements aren’t exactly the same, but they are close enough to get a fairly conclusive result.

phase 1 test results (XBox plugged into an outlet):
Test hours = 172
kW used = 0.30

phase 2 results (XBox plugged into an X10 module):
Test hours = 168
kW used = 0.30

If I had let the test run another 4.5 hours to mimic the phase 1 test then it *might* have added another 0.01 or 0.02 kW maximum. So the overall consumption of the X10 module is actually, and surprisingly, negligible.

Phase 3 will involve the XBox plugged into the X10 module, and the module will be turned off for several hours a day to see how much electricity is actually conserved. It is starting to look like it will be more than I initially expected, at least going by the phase 2 results.

Idle power control – phase 1 complete

Posted by admin on Nov 11th, 2008
Nov 11

After a week (172.5 hours to be exact, or 7 days 4 hours and 30 minutes) I finally have my results of my phantom power test. The total phantom power used in that time was 0.30 kW total – or 300 watts, almost 1/3rd of a kilowatt. Here’s more math for you:

Hours in a year = 8736.00
Test hours = 172
kW used = 0.30
8736 / 172 = 50.79 time measurement units
50.79 x 0.30 = 15.24 kW of phantom power used in one year by the XBox

As of 1am PST on Nov. 11th, I’ve got the X10 appliance module plugged into the Kill-a-watt, the XBox plugged into the appliance module, and the module is “on”. I’ll need to figure out a good way to power on and off the module. I have two basic options. I can manually use the X10 remote used with the modules and turn off the unit before I go to work (@8:30am), and then turn it on after I get home (@around 8:30pm). The other option is to put my laptop out in the garage (where the test is being conducted), and set up a cron job to automatically turn the module on/off. I’m leaning towards the laptop option, but I’m not certain yet.

The main purpose of this part of the test is to see if using the module to totally cut power to the XBox actually saves any electricity or if the module itself will use as much, or more, power. I’m guessing it will actually use more since the module will always be in a powered state – and the amount of electricity saved by cutting the power to the XBox will be overridden and amplified by the constant draw of the module. We’ll find out in a week.

UPDATE: I’ve changed my mind about using the module to regulate the power flow to the XBox. Instead, I’m going to leave everything just the way it is but leave the module in the “on” mode for the entire week. That way we can see how much additional power the module utilizes in addition to the XBox.

Idle power control – phase 1

Posted by admin on Nov 4th, 2008
Nov 4

As I mentioned in my last post, I was going to plug an old Xbox that I had lying around to my Kill-a-watt, leave it powered off for a week, and see how much phantom power it used. I got it all set up last night out in the garage (which suddenly makes me wonder if weather/temperature will skew any of the results in any way….) and this morning, before I left for work, my curiosity got the better of me and I had to check the status.

According to the Kill-a-watt, it had been plugged in for 12 hours and 45 minutes, and had used .02 kW. That doesn’t seem like much, but after 24 hours it should be around .04 kW – again, I know, not much. *But* if you combine that with several other electronic devices plugged in around the house – tv, computer, computer monitor, dvd player, phone charger, clock, rechargeable batteries and/or flashlights, night lights, lamps, video game player, stereo, electric razor, hair dryer….I’m sure you get the picture – then it will turn into something quite substantial quickly. If I had 10 items pulling the same amount of phantom power as my “control” test, then they would be using a half a kW (500 watts) about every 30 hours. Here’s what could happen:

1 device @ 24 hours = .04 kW (40 watts)
10 devices @ 24 hours = .40 kW (400 watts - what a 200+ watt solar panel produces in two hours of full sun!)
.40 / 24 = .0167 kW per hour
.0167 kW * 30 hours = .501 (501 watts, or half a kW)
There are 8736 hours a year (24 hours * 7 days in a week * 52 weeks)
8736 total hours / 30 hours = 291.2 * .501 kW = 145.89 total kW used in a year

Almost 146 kW used in a year from only 10 plugged in and powered off devices. I know I have a lot more than that around my house, how many do you have?

Idle power control

Posted by admin on Nov 3rd, 2008
Nov 3

Due to a recent article on TreeHugger about BestBuy’s naming October 30th as “Vampire Awareness Day” (referring to the idle, or phantom, power consumption of the plugged-in-but-not-in-use electronics in our homes), it brought to mind a few items I had acquired a few years ago that I had completely forgotten about. I have a whole box of unused X10 lamp and appliance controllers just sitting in the garage.

Doing a quick check of the X10 website shows that the prices of the wall modules are still relatively inexpensive. Most of the modules are just plugged into an outlet then the electronic device – be it a tv, stereo, computer, etc – is plugged into the module. Then, using an ifra-red remote, the power to the device can be cut off at the wall, potentially saving a lot of phantom power usage. X10 also has wall outlets as well which allows for whole outlet to be disabled whenever needed. The other benefit to having such a device is for when we are away on a vacation. I can control the modules from my computer so I can turn on/off the lights for security. Pretty nifty.

Over the next few weeks I’m going to be installing many of these modules wherever I feel they may be useful. I’ll update on my progress and document the pro’s and con’s of the devices (and have pictures!). I think I’m going to do a trial run with a specific appliance, maybe a spare Xbox I have, and plug it in for a week with my Kill-A-Watt attached to see what kind of energy consumption it uses while powered off (for the entire week). Then the next week I’ll use an X10 module to cut the power for 10-12 hours a day and compare the difference. That should at least give me a basic baseline comparison. It would be difficult to get a consistent comparison with something that is randomly being used for varying periods of time – like the tv or the microwave.