I've been on a tear of late to eliminate or minimize standby loads. This arises from data revealing that during spring and fall, when HVAC use is minimal, standby loads comprise 25%, 5 kwh / day of our home's total usage.
5 kwh / day exceeds the total usage of our entire kitchen - fridge, chest freezer, range, dishwasher, etc.
At national average electric rates of $0.11 / kwh, each Watt of standby usage works out to a buck a year, so the sneaky little loads add up fast.
An early victory came in the form of learning that the starting battery trickle charger on our standby genny consumes 30-35 Watts. A $40, 10 Watt PV panel from Amazon has allowed me to kill that load while still maintaining the genny's cranking battery.
We have 3 garage door openers, specifically Overhead Door Phantoms. They are quiet and have been relatively trouble-free. Imagine my shock at learning each uses 14.5 Watts while sitting and doing nothing.
Doing the math, the three (aptly named) Phantoms have cost us $200 in standby power since we built the house in early 2008.
Coincidentally, your recommendation is how we are now operating - 1 bay is unplugged, 1 bay is left plugged in (wife and kids) and 1 bay is rigged with an extension cord for intermittent use (my occasional use car)
House is 3400 SF, 5 residents, future aging family apartment included.
We don't "need" 3 garage door openers, and this thread wandered off into a multi-page debate about lifestyles, but my original complaint / inquiry was about excessive standby loads by the garage door openers and how I might mitigate them.
As to your client, start assisting her, but be sure to invoice for advice given and value received
I appreciate everyone's feedback regarding the specifics of my garage door opener standby power.
As to the much wider philosophic differences, I'm "through with engines"
Seems to me the quick easy would be to install a simple switch to shut off power once all the vehicles are in the garage for the night. Most garages have all of their garage door switches centrally located near the entry door to the home. bundle up the positive leads to a switch and let the owner turn it off once the garage is full and on again the following morning.
Unless they are night owls, they should be able to cut their yearly phantom load by 1/3. Cost = $5 plus install time.
Thanks, but alas not so easy - door opener receptacles in ceiling hardwired back to elec panel dedicated breaker. No handy wall switch...
I haven't tried it myself, as we don't pay that much attention to phantom loads in my shop, we're more about the bigger stuff. Still, I would think there would be a way that if you kill the on/off switches, which send a singal to the motor unit, there would be a way to shut that off by the same means. Might have to add ind. relays at the main units as well. Just a thought - trying to brainstorm here is all...
I appreciate the extra set of eyes on this one - I just don't want to incorporate extra complications into operating the doors as such would eat into the convenience of having them in the first place.
The first time I or my wife rolls up and the door won't open, necessitating a walk up around in down and back will be cause for complaint...same when kids are all loaded up and have to get back out and turn power on - we often run late anyway.
I will solve this in a manner transparent to users.
This is a long thread. Quick question. Did you ever find an acceptable solution.
Not yet - the motors are DC, and I've toyed with the idea of running all three off just one of the three standby-hungry big iron transformers. Another option would be to lose the iron altogether and run all three from a mid size deep cycle 12 VDC battery on a very small trickle charger. That would be a substantial rebuild of the openers and I haven't time to take that on. I haven't come up with a wiring diagram, either.
Ironically, newer generation openers take advantage of the DC motors by way of offering a battery backed up opening capability during power outages.
The situation still annoys me greatly - those 3 comprise 1/4 of total house standby load.
Thanks for the feedback. My situation is not as bad. My opener takes 6 Watt at idle, but it still really bothers me. I'm not sure if I would have the ambition dig in to changing the power supply to the opener.
Curt are you sure they are DC? The original transformer if I remember correctly was 12VAC 180VA. That is about a 15Amp max 12volt AC circuit. (per your early thread).
Check and see if you can get service manual either online or from manufacturer. The 12VAC circuit when rectified would get you 1.414 X the 12VAC -- roughly 17Volts DC, so they must have some kind of regulation circuit for the motor - and some really good filtering. My guess is the only time you really hit the full load on the transformer is if the door is jammed.
You can find 12VDC switched mode power supplies (SMPS) that are much closer to the 90% efficient when under load. But they less efficient when lightly loaded. So the suggestion -- if you can find the service manual -- is to separate the motor onto its own power supply - put the receiver on its own small supply. Only enable the big transformer / or new 12VDC SMPS when receiver says open/close.
But then for all the effort and cost of making the changes -- it can be easier just to replace the openers.
Remember that worse case for the motor - is when it is jammed and must immediately reverse. This can happen if a small child falls and is trapped under the door. Garage openers in the last twenty or thirty year are designed to sense the jam and ALWAYS be able to open the door, Changing out power supplies, moving to a battery, or solar panels - if not carefully done - might negate the safety feature.