Measuring the Energy You Use? 184
centdollarman asks: "Everyone keeps talking about how energy is being wasted here and there. Energy bills keep soaring for me, and now I'm back to paper and pencil: just taking notice of the power meter values. Mine is nice, as it has a cute LED that blinks at 1/1000 of a KWh. However, there has to be a better way to do this, and I've started searching the web for someway to count my usage, automatically. Of course, this is easier said than done. It would also be nice to have some way to (cheaply!) measure the power consumption of a single device."
So, for the energy conscious among us: how are you measuring the power you use?
Stating the obvious (Score:5, Insightful)
Extensive tracking on a per device basis is probably going to use up energy itself, so I'm really not sure if that bit will achieve too much.
Weird units (Score:3, Funny)
In these parts, we call that a Watt-hour. What are you, some kind of Canadian?
Re:Weird units (Score:5, Funny)
Re: (Score:2)
Watt/kilowatt hours are a kind of convenience measurement, they are not international system units. Like kilometers per hour, those units simplify day-to-day use, but make things more complicated for calculations.
The real source of the problem is that there has never been an accepted day-to-day system of decimal multiples for the second, which is the SI unit of time. Ultimately, this would be a difficult thing to implement, given that human
Re: (Score:2)
One day is 10000 seconds, 100 minutes, 10 hours. How long is your TV show? A deca. Or half-deca after commercials. How long's it take to run a marathon (if you're worth your salt)? An hour. Fly from LA to NYC? 2.5 hours, or 2 hours and 50 minutes. Time to run the 100 meter dash? 1.04 seconds. A snap of the fingers? millisecond.
But yes, all for naught if you can't find a natural way to calibr
Re: (Score:2)
Re: (Score:2)
Re:Weird units (Score:5, Funny)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:3, Informative)
Re: (Score:2)
So it would blink once a minute.
For an individual device (Score:4, Informative)
Re:For an individual device (Score:4, Informative)
- It is big, so it blocks both parts of a duplex receptacle if you plug it in directly. Use it on a small extension cord.
- It is powered by the source you plug it into, with no retention of results when unplugged, and no light on the display when in place. Bring a flashlight and/or a longer extension cord if you're using it behind an appliance.
But in a well lighted location, it is quite informative.
Re:For an individual device (Score:5, Informative)
I have a Kill-A-Watt, and it has all the problems you mentioned, but it also does everything it promised to do, for cheap. I'm quite happy with it.
Re: (Score:2)
Re: (Score:2)
I have one. The parent's comments are right on target. Despite these little annoyances, it is quite handy. I found mine retail at Camping World of all places.
Re: (Score:3, Interesting)
Re: (Score:2)
I've also used it to measure current draw on my christmas lights [komar.org] to make sure I don't exceed 15 Amps on a circuit - I try to stay under 10 by load balancing.
Re: (Score:2)
That leaves the only real drawback at
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Datacentre (Score:4, Informative)
Very handy for figuring out where our power budget is going.
Google provides the following in quick order
http://www.energyoptimizersdirect.co.uk/acatalog/
http://www.blackbox.com/Catalog/Detail.aspx?cid=1
Enjoy
Conserve it anyway first (Score:2, Insightful)
2. Switch off the lights when you leave a room.
3. The TV doesn't need to run all the time.
Every little bit helps. If you're already doing stuff like this & you're bills are still soaring, then you can try the measurement parts.
Re: (Score:2, Informative)
I hate statements like this because they aren't logical. I'm not saying that it isn't logical to save energy, only that a shotgun approach is not the most logical method. If you want to save energy it would probably help to look at the items in your house that use significant amounts of power. While it may make you feel good to turn off a 40W light, it isn't going to make nearly as much difference compared to raising the temperature of your refrigerator, using your washing or dryin
Re: (Score:2)
Re: (Score:2)
Many other countries don't have them because their cities are old and retrofitting central air into an old house is expensive and difficult (especially if your house is listed as historic).
cheaply measure a single device (Score:2)
http://froogle.google.com/froogle?q=kill-a-watt&h
Re:cheaply measure a single device (Score:5, Informative)
Anyway, a clamp-on ammeter should be in your toolkit. (Get a DC-capable model and watch motherboard/peripheral power draw inside your PC!) Instead of slicing open an extension cord, consider an AC line splitter [google.com] to make your measurements with. The 10-winding side makes small measurements more accurate, and it looks more professional if you end up using it on the job.
Re: (Score:2)
Re: (Score:2)
Don't know if they have one for US voltages though.
Re: (Score:2)
Don't know if they have one for US voltages though.
It may be a good product, but their advertising is horrible. Yes, I hate flash.
They claim it "can save up to 25%" on your electric bill. That's simply a lie. It can show you how much power you use, but it can't save power. I never deal with liars like this - kind of like spammers.
Take a look at this: http://www.tequipment.net/Ideal61-701.asp [tequipment.net]
Same idea, and a good multimeter as well.
Re: (Score:2)
Two things wrong with them at the moment IMHO: too expensive and no history display.
Re: (Score:2)
Re: (Score:2)
In any case I can clear this up since I had a quick look through the online manual. It turns out that you specify the voltage in the setup so you can use it in the US. The default currency is even dollars! Unfortunately, they're going to be about $150 to import so I doubt they get many US orders.
If you know about power factors you will know that
well, (Score:5, Informative)
The only way I can think of doing that, although it would be a hastle, would be to switch off all items in your house and verify that with your little light not blinking, then switch your oven on and time how long it takes you to use a Watt/hour. Then switch that off and see about the lights you would normally have one. This would give you some ideas on how much these things use. As a way of reducing the amount of power that they use you could get energy efficient bulbs (they cost more innitially but less in the long term) and if you need to replace your oven you can look for the most energy efficient one you can find (and if gas or electric is cheaper in your area angle your purchase towards that).
There are also good savings to be made by changing your fridge/freezer and your washing machine to something more efficient (If you live in England we already have a rating service for these, buy only A rated things and you'll save - if not then you'll have to do some investigating on your own)
Re: (Score:2)
Re: (Score:2)
How much does my fridge use/day at setting X? setting X-5?
How much does my oven use to cook dinner? Microwave?
How much power does my rig use playing MULE for an hour? Idling?
You can learn a lot. Listed power is only predictable for trivial devices that are always on, not devices with variable load or duty cycles.
Re: (Score:3, Interesting)
Take this a step further: plug your TV/HiFi/etc into a powerstrip with its own on/off switch. When you're not using the devices, turn the powerstrip off, and get used to always doing that. Then you'll be using exactly zero Watts! European electronic devices can normally be switched off (in addition to any stanby modes), but it seems that this is not the case in the US. BTW: you can get powerstrips
Re: (Score:2)
The small hastle of losing the clock on a TV and having to walk over to do it is nothing when thinking about the energy you'll save
Re: (Score:2)
Replacing Appliances Usually Not Worth It (Score:2)
Say you have a fridge that cost $800 to buy, and you've had it for 10 years. If you think it will last another 10 years (not unlikely), then by throwing it out now, you're throwing out $400 worth of value (using a gross simplification). How many kWh would you have to save over the next 10 years to add up to th
Re: (Score:2)
The benefit part of the analysis is not always simply savings on your electric bill. If you live off-grid or have a whole-house backup power system the reduced energy consumption of a highly efficent appliance reduces the cost of your power storage/generation requirements or extends your backup times.
You can als
Re: (Score:2)
If you bought a fridge 25 years ago it is highly likely it will last another 15 years.
My washer and dryer are over 25 years old. I'll probably get 40 years service from them. My old fridge has a pink steel shell in it and has to date to the 60's. I'll probably get another 25 years from it. But the last fridge I bought which is in the kitchen has broken 3 times in the last 4 years.
Modern appliances suk.
Re: (Score:3, Interesting)
I suppose this comes down to if you can trust the manufactures and what they say. I agree about you with the warming up period, but it is only for a minute or so, and worth it in the long run (if you do indeed get the full 10,000 hours)
Re: (Score:2)
Normal fluorescent lamps lifetime professionally is not rated in hours but in switch-on operations. Leave it on for a month, you might have decreased its lifetime by 0.01%. Toggle the switch 500 times in 1 hour, you decreased the lifetime by 10%. Bulbs are way more resistant to this problem, but switching them on does shorten their life too.
Another factor is working conditions. Primaril
Re: (Score:2, Interesting)
Opposing anectodical evidence: (Score:3, Interesting)
About 4-5 years ago, i started replacing the broken ones with fluorescent bulbs.
Not a single of those ever died.
Re: (Score:2)
Ouch! Fortunately, I haven't had the same bad luck as you.
About three years ago I started switching over to compact fluorescent (CF) bulbs as my tungsten bulbs have died. The ones I've bought have a 7 year guarantee (cheapos from Home Depot.) I've taken to writing the install date on them with a sharpie marker before putting them in the fixtures. Yes, I know I'll never find the original
Re: (Score:2)
I also like the ability to get more light from a fixture rated at 60W. The biggest problem I have with CFs indoors is that I can't use them in chandeliers or other fixtures where the bulbs are a visible part of the design -- they're simply u
Re: (Score:2)
Insane measuring (Score:2, Informative)
Easily said. (Score:3, Insightful)
Sure I do switch off the obvious things. Then still my bill is high. Then I check: The monitor (22" CRT) is rated at 40 Watt in standby mode. The ethernet switch is pretty hot. I have no idea how much the laser printer needs in stand-by, but likely not all that little. All these toys plugged into the USB hub, do they remain off when I power off the computer? The BNC ethernet wire was shocking me with electricity. I grounded it, but how much does leak to ground that way? The grounding sparks a little when disconnected. If I leave the battery charger plugged in, it's warm even if it's not charging any batteries.
Re: (Score:2)
I always hated thinnet's little electrical fangs. Remember to only ground one end.
If I might ask... Why are you still running it?
Re: (Score:2)
Re: (Score:2)
If the 22" CRT really uses 40W in standby, put it on a switched outlet. If your computer documentation doesn't say whether USB gets standby power, measure it with a meter. Unplug your battery
Re: (Score:2)
Watt Meter for European Sockets? (Score:2)
Where can I buy an inexpensive Watt meter for use with European sockets? Preferably in the Netherlands, but any place that will ship to the Netherlands is fine, too.
Re: (Score:2)
(i know that reichelt, ELV and conrad catalogues have them listed)
Even for RC planes (Score:2)
two cheap AVOs (Score:2, Informative)
Re: (Score:3, Informative)
If you don't know what you're doing, a real laboratory instrument will be much, much less accurate than an inexpensive device specifically intended as a
My UPS has a report (Score:2)
Of course, a 50 pound battery isn't very portable, and I wouldn't drag it around to the refrigerator, dishwasher, lamp, or garage. But I'm mostly interested in the computer's draw anyway, sin
Handy Display (Score:4, Interesting)
How can we expect people to conserve without any easy-to-see meausrement of consumption.
-Geoff
Re: (Score:2)
It's low power, compact,
Possibilities (Score:2)
For automation, it getst expensive. Basically you need a power meter with some sort of interface. I expect this to be in the $300 plus price class, since it is professional equipment and not mass-market.
AMR meter (Score:3, Insightful)
See if you can get your power company to install an electrical meter with radio-read capabilities. I'm more familiar with water meters, which come in at least two flavours - radio read that sends a signal back in response to a message from the meter reader (using a hand-held meter reading "gun"), and a unit which sends a small packet of meter information every 1-5 minutes. Some info on Wikipedia about automatic meter reading [wikipedia.org] (AMR).
Then all you have to do is possibly reverse engineer their protocol, or at least connect a radio transceiver to your PC and program your own meter reading software.
Of course, I think you are worrying too much about having instantaneous data. I would approach your power usage as an environmental auditing problem. Your power use is more a result of your long term habits and the devices you use. Does it really matter whether your computer and 22" CRT use 600 or 800 watts combined when you know that a Mac mini and LCD would probably use half of that or less? Do you really need to leave your computer on overnight? Does it matter that you have energy saving light bulbs if you leave every light in the house on all day? Is your refrigerator more than 10 years old? Are your appliances energy star rated? Do you hang your clothes to dry outside whenever you can, or do you use an electric clothes dryer?
For power consumption, average long term values are more going to be more important than real-time numbers. By changing your habits and the way you use energy, and tracking the changes and the effects on power consumption as you do that, you'll have more of an impact, that will last far longer than your current fascination with your power usage. You might want to measure the total energy used in a day or a week by various appliances such as your fridge or your TV, in order to determine whether it makes sense to replace them with more energy-efficient models. Beyond that, electrical powered devices use power, just like cars use gasoline. If you choose to use them, you're going to have to pay.
(cheaply!) -- Is free cheap enough? (Score:5, Interesting)
Check out the standby power consumption. I was surprised by my powered subwoofer taking 8 watts when it's "off". Along with the TV (6 watts), receiver (6 watts), and DVD player (4 watts), that was enough waste to make me turn them off at the power strip.
Turn off everything you don't need (Score:2, Insightful)
This seems pretty obvious but I constantly see people leaving stuff turned on when they're not using it.
Leaving the TV set on when you're not watching, leaving the light on when you're not in the room, leaving the water running while you brush your teeth, you name it, wate of energy and natural resources seems to flow in some people's bloodstream!
And those poor bastards who use that lame-excuse-for-an-instant-messaging-program called MSN Messenger have a special way of wasting energy: leaving their comp [borfast.com]
But I know the culprit (Score:5, Informative)
For my house, A/C is by far the biggest chomper of energy. During the summer months my electric bill gets as high as $270, and during the winter it gets as low as $70. Not only that, but on hot (97 degrees f) days my upstairs never gets cooler than about 78f.
It's a fairly new house, so I can't simply replace the upstairs unit, but I think it's clear that they didn't install a large enough one. What can I do? Put another powered roof ventilator in? Add more insulation in the attic? Put a radiant barrier on the underside of my roof?
This website [ornl.gov] helps to answer these questions. It provides some analysis of the different scenarios. Dunno if the analysis is accurate or not...
Re: (Score:2)
Good luck.
Same here. (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
One thing people can do is to put their other resources to work for them. Most people can't afford to retrofit a geothermal heat pump underneath their house, but there's other options!
Do you have a pool??? Think about how AC units work: they remove heat from inside of the house, and move it outside into the atmosphere. Air, being an excellent insulator, is probably the worst medium to discharge excess heat efficientl
Re: (Score:2)
Centameter (Score:2)
I use a Centameter [centameter.com.au]. The measuring device is installed in the meter box. You carry around a wireless LCD display that shows power usage in either kWh or A. I managed to reduce my house standby power usage from 0.44kWh to 0.21kWh because I discovered some appliances with atrocious standby usage; they're now turned off when not in use. That's going to save me $282 per year - I pay 14c/kWh - so the meter has paid for itself already.
Indirect solution (Score:3, Interesting)
Gasoline produces 32 megajoule/litre, 1 kWh is equivalent to 3.6 megajoule so 1 litre of gas ~= 10kWh. 1 kwH of electricity ranges from 5c to 25c depending where you are.
For Canada:
1 MJ of oil energy ~ $0.04
1 MJ of electric energy ~ $0.03
How much is a MJ of of electric or oil energy where you live?
Re: (Score:2)
2 x 1000w HPS lights == 720 KwH ~ $0.06 == $43.20 per month X 3 months == $129.60
That would be 2Kg of MJ for $129.60
Kill-A-Watt (Score:2)
Search for Kill-A-Watt.
It will track the consumption of a device (or even a breakout block with 4 sockets, with this thing in the wall) over a period of time.
The alternative is replace the power distribution box in your house so you can monitor each room's usage.
For the true geek who needs to know his power usag (Score:2)
http://www.edcheung.com/automa/power.htm [edcheung.com]
I read about a great solution some time ago (Score:2)
http://www.kondra.com/circuit/circuit.html [kondra.com]
It's very involved and detailed and it looks like anyone who tried to replicate the system would have to spend quite a bit of money, but then you'd have access to all of the data you could ever want about your power consumption.
I'll include the last page of the linked
network enabled meters (Score:2)
Umm buy a meter? (Score:2)
Or even better yet how about that thing on the side of your house that has the little shiny spinning disk.. Its not from mars, it tells you total energy useage for your place, both in real time and elapsed.. Its how you get billed each month. Its called a watt-meter, go figure.
Re: (Score:2, Funny)
Re: (Score:3, Interesting)
Or get a power-shower. Or, even better, shower at the gym. I do it because (a) it forces me to stay in the habit of going to the gym every morning, and (b) someone else pays for my hot water. Sure, I pay a gym membership, but I would pay it anyway (at the same price) just to keep fit.
Simple, inefficient solution: save your own energy, use someone else's.
Re: (Score:2)
"but I would pay it anyway (at the same price) just to keep fit."
If there were no showers at the gym, would it be the same price? If the cost of energy doubled, would it still be the same price? The answers are no, and no, you irrational punk.
Re: (Score:2)
Good show,
-l
Re: (Score:2)
People use electricity to heat the water tank? How inefficient.
Re: (Score:2)
You could probably find some on Google [google.com].
Re: (Score:2)
1) Flicker. Easy to solve with a good high frequency ballast, but do you think the lowest-bidder bulbs at Home Despot or Walfart are going to have one? No, they'll flicker like a cheap neon sign in a red-light district.
2) Buzz. Pretty much the same issues as flicker.
3) Light quality. The color rendering index of an incandescent bulb is 100. That of a fluorescent, anywhere from in the miserable 50s to the not-so-g
Re: (Score:2)
1. Flicker is a non-issue on my bulbs. I can't percieve it at all, neither can anyone else. Some of them are surprised to learn that I have CFLs in my lamps and fixtures.
2. Buzz is a non-issue too.
3. Light quality is tougher to measure. While it looks fine to me, I wouldn't be surprised to see that it's missing certain portions of the spectrum. However, this is one of the things where brand matters a lot. The bad CFLs have absolutely terrible c
Re: (Score:2)
Light quality is easy to measure. The measurement results a couple of numbers -- color temperature, and CRI (Color Rendering Index). Color temperature can be easily manipulated by the bulb maker. CRI is much harder. To get a decent CRI you need to use several phosphors, some of them expensive. And you still don't even approach that of an i
Re: (Score:2)
Another good measure is if the bulb is on before your finger leaves the switch.
Re #6 (Score:2)
I happen to recall I got close to 10 years from at least one of the previous bulbs. I had to replace both (I was using 2 back t
Re: (Score:2)
In the second scenario, if greenhouse gas effect dropped, you would need to heat more in the winter, but cool less in the summer from cooler summer temperatures.
Re: (Score:2)
I call that Americanitis, If enough is good, too much is better!