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Posted By: twh Home Automation - 07/02/08 05:00 AM
One of our wholesalers is pushing a home automation system that will save electricity, extend the life of light bulbs, and provide security. I'm not against every new idea, but my email inbox is full of great ideas that need a little extra scrutiny.

My understanding is that the system dims lights to 80%, to save energy and extend the life of the bulb, and turns the lights on automatically to make the house look occupied.

Wouldn't it be better to use compact fluorescent lights to save energy?

When incandescent bulbs are no longer available, will it be cost efficient to use dimmable CFLs? Do they last longer if they are dimmed?

Isn't turning lights on when you are away the exact opposite of saving energy? Wouldn't an alarm system be energy efficient and a good deterrent to intruders?
Posted By: renosteinke Re: Home Automation - 07/02/08 02:55 PM
Advertising hype is nothing new. It's kind of like those 'gas saving gadgets' .... despite brisk sales, I have yet to see someone pull into a gas station to drain the excess from their tank.
Posted By: gfretwell Re: Home Automation - 07/02/08 03:02 PM
I think the best energy saving for lighting is a 2 level system with task lighting and low intensity room lighting controlled by occupancy detectors.
In real life I doubt lighting is the main load in any house these days. It is certainly insignificant in my $250 electric bill.
Posted By: renosteinke Re: Home Automation - 07/02/08 03:49 PM
Quite true, Greg.

I recently went through this with a plant manager, who was convinced his lighting was the cause of his high electric bills. I wanted to do a survey of every circuit in the plant, to learn exactly where the power was being used .... he didn't want to do that.

Now, several months later, he has admitted that the problem seems to be related to whether he's welding that day, or not.

In my home, the electrical use seems to break down as such:
#1 The fridge
#2 The water heater
#3 The fish pond
#4 The computer / TV / Stereo
#5 Lighting
#6 Everything else.

How do I know? Simply put, the "Kill-A-Watt," which I used to measure most appliances and power strips, plus data from when the water heater was metered separately. (Note: I've started making new measurements just for this thread ... see post below).
Posted By: gfretwell Re: Home Automation - 07/03/08 01:27 AM
I have a pool and a spa that suck some juice but probably not much more than the 4 PCs that run 24x7
Posted By: SteveFehr Re: Home Automation - 07/03/08 10:51 AM
Christmas lights kill me in december. One year we put up a bazillion lights and decided since we spent so much time and money on the decorations, and they looked very nice during the day, too, we'd just leave them on 24/7 and left them up well into january. A very unpleasant $300 increase in our electric bill followed...

The major part of my electric bill is heat, followed by AC.

Hmm... I wonder if we could repack our freezers and drink the extra beer, and turn off the 3rd fridge that's sitting in the garage?
Posted By: gfretwell Re: Home Automation - 07/03/08 01:10 PM
I have a fridge outside in my pool bar. Same deal.
We are not really that big on the Christmas lights tho. I gave her 20 amps.
Posted By: renosteinke Re: Home Automation - 07/03/08 01:41 PM
Timing is everything ....

Completely unrelated to this thread, i was looking at some design info last night. For the kitchen, the author claimed that fridges made today use 1/3 the power of those made 30 years ago.


Just for grins and giggles, I'm going to re-visit this post over the next week. Using the "Kill-A-Watt," I'll post the results of my latest power use. All measurements will be over a 24 hour period.

Total Use (PoCo meter):9.41 kwh (PoCo meter doesn't read this fine; reading will be taken over longer term and averaged.)
Hot Water (Estimate): 4.67 kwh (From old PoCo bill that had separate metering. Daily average.)
Refrigerator: 2.98 kwh
TV / Stereo: 0.09 kwh
Computer / Pond: 3.61 kwh
. (Will break out later. Pond figure will be low, due to little need for heating,)
Primary Lighting: 0.71 kwh
Night Lights (Estimate): 0.03 kwh

(Keep watching this post ... I will be 'fine tuning' with additional measurements as time goes on.)
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