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Everyone's talking about cost savings, or system wear.... I'll attack it from a different angle....
Could I lower my bill by powering down some servers? Certainly. However, they serve a purpose, and they can't serve that purpose if they're offline.
Why not buy a Kill-A-Watt?
It seems it would be less dangerous.
You should also buy a Kill-A-Watt to measure everything, like the wattage it’s using, amperage, and cost to you as well… they’re cheap on Amazon and really handy around the house
P3 International P4460 Kill A Watt EZ Electricity Usage Monitor [link]
Absolutely! Only way to know for sure is to get a product that will monitor you Kw consumption. In my old place I had a non-energy star rated commercial refrigerator, and it easily cost me extra $40/mo in electric bill.
As an aside note, if you're looking to curb your electric bills, look into the usual LED lights and home automation. These really help in reducing your general energy usage. Smaller carbon footprint is just a bonus in addition to having a much lower utility bill each month.
If they're AFCI it's possible that one of your appliances is shorted to neutral and causing it to trip.
In my office/server setup, I use a Kill-A-Watt to monitor how much power is being drawn. This will tell you if you're getting close to using that 15 AMP limit.
Mine does. Here ill edit in a link to amazon.
It records the amount of electricity used and also allows you to set a price for the electricity and then over time it will add your costs up automatically.
In addition to what other folks have recommended, you might consider picking up a Kill A Watt (or similar) device. They make it easy to determine how much power a specific appliance is using, and can be a big help in tracking down this sort of problem.
Have you measured the power consumption of the fridge? Seems like it would account for maybe $40-$50 a month at most.
Plug it into a meter and see if that’s really what’s taking the power.
It would be good to have a proper watt meter, this is my go to for people having issues like you are experiencing: P3 International P4460 Kill A Watt EZ Electricity Usage Monitor [link]
That being said the AC units really vary up and down in use as they get going. Some start and take a ton of power, but many start the fan and wait a bit to start up the compressor which depending on the size of the unit would take all of the capacity of your line. (there should be a sticker showing maximum amps or locked rotor amps or something like that. There are new AC units that are specifically made to
be much more efficient and they ramp up gently so work in many more homes.
Hope that helps.
Kind of sounds mechanical or electromechanical, like the sound a relay makes when it closes.
What model PSU? Have checked the manufacturer specs on AC input amps? For example, a 1600W EVGA supernova, according to evga website, draws up to 17A on 120V, or 10A on 240V (these are max figures). Is it possible between the PC, monitor, and whatever other goodies you have plugged in that you're nearing the threshold of the surge protector?
Maybe you could try plugging a kill-a-watt meter into the wall, and plugging the surge protector into the kill-a-watt and seeing how much input current youths drawing through the strip?
Electricity is priced per kilowatt-hour (kWh). The average price per kWh in the us is around 12¢. If your bike has a 500Wh battery, that would make the cost to charge it from completely empty to completely full around 6¢. That's roughly equivalent to:
Also keep in mind that you're not usually charging the full 500Wh of your battery. If your roommates are concerned about the impact to the electricity bill, you can get an inexpensive kWh meter on Amazon. That will tell you exactly how many kWh your charging cycles use. You should be able to find your kWh rate on your utility bill. It might be lower than 12¢.
I'm a little late to the party, but I tested the power draw of my system.
Using a Kill-A-Watt meter I drew:
I'm no expert, but I'd venture to say that the 3090 would work in my setup comfortably. It looks like I have ~450W buffer with my normal use (gaming, school/web, and programming). The best thing you can do is get this bad boi and test your current power consumption with the various ways you use your system normally. Maybe a more knowledgeable person here can advise, but I'd want to have at least 150W buffer at max GPU load to even consider the 3090 going into my system. It sounds like you will have more than that.
I bought a Kill-A-Watt and tested all of my electronics and appliances so I knew what to worry about and what to let go.
For me saving 27¢ a year on something isn't worth stressing over.
But it did prompt me to replace my family room refrigerator.
If you have them (which it sounds like), just get a Kill A Watt and plug them into it. No more calculating or estimating.
If you have them on a UPS, your UPS might tell you too.
How far down the rabbit hole do you want to go?
I plugged mine into a dimmer switch and this thing...
I'd get the smoke rolling at about 150 watts then turn it down to 60-70 watts for the duration of the smoke. It would keep going after you switched it off most of the time but it wasn't reliable. At 60-75 watts it was 100% reliable and it didn't over smoke
Get one of these.
It won't protect from overload, but it will show you what kind of power stuff is using.
Anyone that is interested in learning their power consumption should get one of these:
**You can even plug in your local power cost and it will calculate it for you.
I use one on my home lab to see how much extra things draw (put a powerstrip on it and everything else into that). I'm creeping up toward 100 Watts on 120V. I eventually want to get an UPS that can run my setup for at least 3 hours so I would like to keep the total power consumption under 150 Watts if at all possible.
Internet - Fios ONT
Router - Netgate RCC-VE-4860
Switch - Ubiquiti US-24
AP - Ubiquiti UAP-AC-HD
Server - Rpi3
Buy a cheap power meter, [link]
Or basically just search Kill A Watt.
You use it to see exactly how much it pulls from the wall and that'll tell you what UPS will and won't work.
Also they are just handy to have around, at least in a shitty old house like mine that doesn't have very many circuits.
Have you manually OC'd the card, or are you using stock settings? I get an extra 4-5 Mh/s on my 1080 with an OC. Comes at the cost of slightly higher power draw. I use one of these to monitor the electricity I'm using:
I'm assuming you're outlets are different because of your "0.3€/kWh" comment, but I'm sure there's a euro style one on amazon.
> The best way to see how much power you're using is with a Kill-A-Watt or something similar.
I used to have one of those things! Not that exact model though and unfortunately it broke. Back when it was new I could switch it between Volts, Amps, Watts, Volt-Amps and kilowatt hours. Now though, whatever I press it just stays locked on the volts mode.
> You could also downclock and or undervolt
Oh no... This all sounds like really basic stuff, but yet, 15 years of building, and I've never heard of this. Undervolt? Does that mean like flicking the 230v switch on my PSU to 115v?
(Slight sarcasm, whilst I'm not sure what you mean - I'm guessing it's a setting in the BIOS maybe? I do know what flicking that PSU switch does. A guy from my school did it way back when. Blue flash, loud bang, lots of smoke. His dad was uh, not a happy bunny. Oddly enough they're all auto-sensing these days)
It probably won't be running at full tilt just running a node. You could also downclock and or undervolt it so it keeps power to a minimum.
I run a dedicated node system on the AM1 platform for Bitcoin and Gridcoin. Uses 40W from the wall. The CPUs on the AM1 platform are 25W TDP.
The best way to see how much power you're using is with a Kill-A-Watt or something similar. My node is connected to a UPS that displays how much power is being used.
I see. Well, I can understand that from a safety and CYA perspective. But say you/your company were to measure one of the computer's power draw yourself with one of these and see that you could get away with smaller PSUs. At that point you could quantify what that would gain for you with the contractor on paper and determine whether that's worth the amount of expansion it would afford.
Hey there - I too have a decommed server from my office.
I have a HP Proliant ML 350G5. Close to what you have. This thing is HUGE and LOUD. Also very power hungry. I don't know why I haven't just gotten rid of it already. I am not using this thing for anything... Just sits in a closet. I instead am using a retired desktop (also from my office) a Dell Optiplex 9020 as my FreeNAS host. Does everything I need in terms of a NAS.
Depends on what your use-case is for your server. Are you looking for pure storage? Are you spinning up some VMs?
To satisfy my VM curiosity, I've purchased a Dell Poweredge R610 off eBay for ~$170 for all of my virtualization exploration.
The server you have CAN definitely do any of the above, but you will need to take some time to identify what roles you have in mind for this server. If you want it running 24/7, you might want to invest in a killawat meter to see how much it'll cost in electricity bills to keep it on.
That's too much, something is eating your power. I'd use something like this and plug it up to all your devices and figure out if it really is your computer eating all that power. If it is then maybe you need to change the power supply out. [link]
You need a usage monitor to know how much the power supply is taking from the wall socket (what you pay in your monthly bill). For the real power consumption, you need to take into account the power supply's efficiency.
For example, if the PSU needs to give 400W to the components and the efficiency is 80% then it will take 500W from the wall, which means 100W are lost in the AC/DC conversion.
I was just using one of these guys. It does measure PF and also provides the actual wattage.
Though as others have made clear, it would seem the power draw is coming from the thermostat. Which makes sense considering it has a simple on-board CPU, WiFi, etc.
Got it. It sounds like there's at least one more variable to consider in the calculation--a variable that I can't measure/control.
A new wrinkle has been added to my investigation. I now am in possession of an electricity usage monitor (similar to this). It looks like I won't be able to plug my air con unit into this, since it does not appear to have a plug (I guess it is hard wired into the power in the walls somewhere?). But could I still use this monitor, in conjunction with my other appliances and my apartment's power meter, to make any measurements that would help illuminate excess power consumption (if any) from the a/c unit? I think the answer is 'no,' but maybe I can bounce it off you.
I say 'no' because this new electricity monitor doesn't really give me access to any new information about the a/c unit. It gives me new information about any appliances plugged into the monitor. But since I can't do that with the a/c unit, the monitor is irrelevant. It just sounds like there are too many variables that I can't control and/or isolate.
THEORETICALLY though, if I was able to attach a proper wire and plug to my air con, could I plug it into the monitor and glean any information about excess power consumption? Or are there still additional variables that I wouldn't be able to measure/control? Please understand that I have absolutely no intention of trying this. I have already made up my mind to move apartments, and for many many reasons I would never attempt such tinkering. I just want to know for my own edification.
Make sure you buy one that is rated for a high enough load on the battery-backup outlets. The "surge protection only" ports can take any amount of power (below your breaker's rating for that circuit), but the "battery backup" ports have a specified draw limit that will trip the UPS if you exceed it. The rating on the UPS is for how much load can be put on all battery backup ports combined - so if it's 330w, you can't exceed 330w even if it's on AC power. If you do, it will overload and whine at you.
You can figure out the load of your system by using one of these guys on your current power strip for both systems: [link] then you can size your UPS appropriately.
The best tool that I use is a watt meter. This one is pretty much idiot proof. It shows you watts, amps, ohms, and shows you the total usage over the course of a day.
My server is a Xeon, 16GB RAM, 10 drives, a few other bells and whistles. Under load it uses about 230W/hr.
Every year, you should go to the circuit breaker box and turn off the big circuit breaker, then turn each smaller circuit breaker on and off a few times before turning the big breaker back on. Test GFIs by pressing the test button and then the reset button, but it's possible for there to be loose or weak wire connectors at a GFI.
Where we used to live, at least 3 outlets and switches failed because their back-stabbed connections loosened. Get a Kill-A-Watt, about $15-20, and test each AC outlet by plugging a hair dryer into the Kill-A-Watt and observing how much the voltage drops when you turn on the hair dryer full blast. If it drops more than about 6 volts, there could be a bad connection -- loose contacts on the outlet, poor connections behind the outlet, or even a bad splice upstream.
You can buy a Watt Meter and see what your power draw actually is. Just stress the GPU/CPU while plugged into this thing and you can see how close to the 500 Watts you actually are.
You will be fine but it will give you a good idea of how much you can add to your computer before needing to upgrade your PSU.
I'd say this all depends on exactly what kinds of surges or dips we're talking about here. OP, consider picking up a Kill-A-Watt. They're quite useful for this sort of issue and will help you determine whether it's a more serious issue or not. You can probably find one locally, which would be quicker than ordering one online.
As far as a "power srip", the quality of those varies widely. Without a specific model, nobody can definitively say if you're adequately protected. In the absence of any real details, I'd say it seems you're probably fine but best to be sure.
We use about 15 killowatthours/day and our bill is usually less then $60/month.
There are a few easy ways to cut your energy use if you're interested.
If you have electric heat, keep your thermostat as low as you can stand it. Electric heat is expensive.
You can turn the temperature of your hot water heater down. This will save quite a bit, but don't turn it too far down because you can get algae growth. There are plenty of guilds online to show you how to do this.
If you have cable, put your cable box on an automatic timer to turn it off at night. These things use a fair amount of power even if you're not using them. Actually, lots of appliances use a fair amount of power even when they are ''off''. Get a kill-a-watt meter to see how much they are using. Anything sucking too much power gets a timer switch to turn it off at night or during the day while you're at work.
Replace any regular light bulbs with CFL's or LED's. I like LED's better because the light quality seems nicer. I don't like that CFL's take forever to ''warm up.''
For monitoring actual power usage I would recommend buying a Kill-A-Watt or similar power monitor. They work great for figuring out exactly what each device in your house is using. https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q
It’s going to be pennies. Your scooter is almost certainly not to blame.
This might help: [link]
And if you need to prove it, buy this: P3 International P4460 Kill A Watt EZ Electricity Usage Monitor [link]
> It's not in the lease agreement at all as it was once just included in the rent, then all of a sudden the landlord said that the bill was going too high and we would have to split.
That is illegal. Your landlord is violating the terms of your lease. How the power is metered/supplied is a fundamental lease term, and he'd have to either offer you a new lease (which you could happily refuse to sign and insist on sticking with the old lease until the term was up), or abide by the terms of the old lease until it was up and then put the power change in the new lease. I suggest read through your lease- if it says power is included for $x/mo anything he's tried to charge you above that is a breach of contract.
That said, you didn't ask for legal advice, you asked for technical advice, so I will try to help.
First, to understand how power is measured. Power flow is measured in amps or watts- the specifics don't matter, other than to know volts times amps equals watts. So a 15 amp circuit, at 120 volts, can handle a maximum of 1800 watts. Amps and watts are both momentary measurements of flow rate, like gallons per minute on a pump.
Power usage is measured in kilowatt-hours. 1 KWh is the amount of power consumed if you run a 1000 watt consuming device for 1 hour. Or, a 500 watt device for 2 hours, or a 2000 watt device for 30 minutes, or a 10 watt device for 100 hours. You get the idea.
Every electrical device is marked with its maximum power consumption on the 120v side. So for example the gaming computer marked as 900 watts, might only use 30-60 watts when idle, and 450 watts under load- it just has a power supply capable of handling 900 watts even though it will never actually use that much.
One way to measure power use is with a kill-a-watt meter. Plug it into the wall, plug the device to measure into it, and it will tell you how much power the device is actually using. Leave it plugged in and it will tell you the total KWh consumed.
A few things to expect- if you use LED lights, your lighting won't draw much. A 100W incandescent bulb pulls 100 watts, but the 100W equivalent LED is only 15-20 watts. Laptop computers can pull 40-120w while running or charging, but on standby (not charging, not on) should be under 10 watts or so. Kitchen appliances frequently pull 1000+ watts, especially anything with a heater (toaster oven, microwave, air fryer, etc). Cable TV boxes are a notorious vampire- they usually keep all their decode circuitry on 24/7 to get software updates, so they can be using 30-60w 24/7.
The big consumers are often things that are hardwired. A stove or oven pulls a few thousand watts when operating. Same thing with a central air conditioner. Most of those have their rating in amps- keep in mind they run on 240 volts not 120v so multiply accordingly. Electric plug in heaters will be 1200-1800w, central electric heat will again be in the thousands of watts range. Electric washing machines are usually a few hundred watts when running, electric dryers are like ovens, few thousand watts. Dishwashers can pull 1000+ watts during a cycle as they run their heating coil to heat the water.
A better way to measure power is right at the breaker. If you have a breaker panel in your unit, that's a good thing. There are a few gadgets where you clamp sensors around the main feed wires in your breaker panel, then it can sense how much power is flowing and tell you your total usage over a month. This of course requires you to have a breaker panel in your unit that feeds ALL your unit's power.
Ultimately though I suspect no matter how much tech you throw at this, you will end up with a legal problem. If you get billed for 350 KWh, and you can prove you only used 100KWh (which is ONLY possible if you have a clamp meter in your breaker box), then you will need to persuade your neighbor to pay their fair share, which may require persuading the landlord to demand they do it.
Hope that helps!
TLDR there is (currently) not a practical way to do this with batteries, at least not something like this battery pack you linked. Maybe a truck bed full of lead-acid batteries and a stout inverter would do it, but it is not ideal.
You would need to measure both the peak and sustained power draw from your system at whatever volume you desire, then roughly calculate the watts*hours to figure out what kind of stored power you need. While the (claimed) 3300 watts peak of that battery pack may be sufficient to run the amps in your speakers, the (again, claimed) 1260 watt-hours is probably not going to last long. If your system draws 1000W continuous then the battery would run it for roughly an hour. If it was 500W continuous then 2 hours.
You can measure the draw of your system using a kill-a-watt or similar device, although you may need to measure the sub(s)+tops separately. (There are other ways to do this, but this is the easy/user-friendly way) You would plug them into the device and run them at your desired volume and program material for, say, 10 minutes and calculate the watt-hours used, then multiply to get your runtime. So the kill-a-watt may tell you that your subs+tops combined used 200Wh in 10 minutes. That would come out to 1200Wh for 1 hour runtime using the very expensive battery you listed. Also keep in mind that device is probably exaggerating its real power ratings so I'd fuzz those numbers down somewhat to get a realistic number.
More practical would be to buy or rent a quiet inverter generator and run a long cable down to the beach, if that's possible. The Honda EU3000is or Yamaha EF3000i are good choices for this kind of setup. If you can park a truck 100-200 feet away and run the generator in the truck bed (maybe with some material to muffle the sound), that will work. Use heavy (12ga) cable for the power feed. If that's not possible you're looking at lots of batteries and a DIY battery-inverter rig. Ultimately a gas generator is the way to go here, unfortunately.
Hook it up to a kill-a-watt ([link]) and test its power consumption. I am pretty sure they probably use less wattage than you think. Especially after it initially warms up.
Energy evaluation device eg. Kill-A-Watt? https://www.amazon.ca/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q
Understanding power consumption in general is good. I see people here commenting about LED lightbulbs, and turning lights off. But once you're on LED light, the power consumption is neglible compared to, say, a space heater or tumble-drier.
The other answers about checking the power requirements of the devices and comparing their total to the ratings of the extension cords and power strips are correct. If you're unsure of the device requirements, using a power meter can reassure you.
If you want to understand where the popular concern over plugging multiple power strips into each other comes from, and what parts of it you should actually be concerned about, this video is great.
Is this what you're referring to? Or is there a more ideal one to consider?
Here’s one on Amazon
P3 International P4460 Kill A Watt EZ Electricity Usage Monitor [link]
Called a kill-a-watt meter
Not sure that youre missing anything, but now that youve made me aware of it, Im slapping a Kill-A-Watt (LINK) on all of my panel setups one by one and checking into this for my setups. If this end up being the case for me Ill have a problem and will be unplugging them or using a smart plug/switch. I had vampire sapping electronics and I would have thought NanoLeaf would have figured out how to be efficient. Obviously not with their DNS requests though (LINK)
I am a cheap bastard and keep my house at 50F and bedroom at 64F, to keep my fingers warm I use a 500-watt desktop heater. My electrical rate is 10 cents a kWh so it costs me 5 cents an hour to run. So an hour a day is $1.50 a month.
Edit: from my other post -
I have 3 of the newer P4460, they have memory backup so if you lose power your data doesn't get lost. You can also enter your kWh cost and it will keep a running total.
For my whole house, I have an 8 circuit current transformer set up in my breaker box that gives real-time data down to the second to a phone app.
The three possibilities I can think of are:
The power measuring circuitry is not designed for accuracy near idle.
GPU-Z is reading the sensor wrong.
Your system is misconfigured in some way that prevents your GPU from clocking down at idle.
Maybe try an external power meter (anything above 60W at idle is cause for concern), or a first-party app.
First, determine what watts average you are trying to supply power for. I'm talking real world idle/running figures. This meter on Amazon is good to figure that out and is fun to use around the house.
Then determine how long you want/need to power your electronics for when the power goes out. Either on the side of long enough to shut everything down or upwards of like a 1-2 hour runtime.
Then take a look at the UPS runtime performance chart. It will usually be a graph that shows runtime for various watts. You can find this on the manufacturers product page.
Also, you will have to decide if you need a modulated or pure sinewave UPS. The latter is between 50-100% more expensive. Some electronics are finnicky with how clean the power is and might require pure sinewave.
Another value you have to be aware of is the amount of watts the UPS can handle.
My situation is my entire lab pulls 90 watts on idle and when the server steps up, I can see upwards of 120 watts normally. For me being under 100 watts normally, and wanting a 1 hour runtime with everything running, and pure sinewave, I settled on the following 750VA UPS. It will give me an hour for 100 watts and if I configure my server to shutdown when on UPS power, I can extend my network runtime to about 1.5 hours. Also, it is capable of handling up to 500 watts so I have some room to grow into as I'll only be utilizing about 20% of it's capable max.
Product page - [link]
Product page runtime graph - [link]
Another good thing to have for setting up your power distribution is a Kill-a-Watt meter that plugs into the wall, then you plug the load (pins) into it. https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q/ref=sr_1_9?dchild=1&keywords=killawatt&qid=1594923110&sr=8-9Will tell you the line voltage, and the power being drawing (Amps, Watts). After checking one circuit, you can unplug it and move it to another circuit. It is code to only load circuits up to 80% or so of the circuit's rating. This protects your wiring from overheating.
Thanks. I had a Kill-A-Watt but I loaned it out to my sister and now I need a new one.
I used a portable in a (smaller) apartment and it never was that expensive (when scaled for number of units). I would buy a Kill A Watt and try to isolate the offending appliance: https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q/ref=pd_lpo_sbs_79_t_1?_encoding=UTF8&psc=1&refRID=JR2HP87D5G1W67W2KJYF
Maybe just use one of these:
414 watts on my PC w a 1070 and 1070ti mining. the kill-a-watt is your best friend.
Best way would be to get a watt metre, and monitor the electricity usage.
Then you can easily calculate your GPUs electricity cost as follows
Watts * 24 hours * 30 days / 1000 = X kWh
Then you can multiply the result with your electricity rate.
X kWh * your electricity rate = cost of running the GPU for a month
If your expected revenue in terms of coin price is more than the cost of running the GPU, then go for it, otherwise it would be a waste.
For a quick rough estimate, I would suggested looking at [link]
I'm not getting that option for the P3 with Pro Ebiz as the seller.
I mocked up something like this:
PCPartPicker part list / Price breakdown by merchant
Fairly low power CPU and GPU. CPU has a 65W TDP and GPU has a 75W TDP.
The CPU is not going to come close to that. Even under load, it will likely be around 50W. The GPU will hit right up against that that 75W barrier.
But for the sake of thoroughness, we will account for the full TDP of both: 65 + 75 = 140W.
The rest of the system combine will be less than 100W. Even 100W is a pretty heavy over estimate: 140W + 100W = 240W.
So, for 240W, you get a pretty capable 1080p gaming PC.
In real world use, power consumption will likely be closer to only 200W.
Actually, given this information, you can upgrade to a GTX 1060, if you're comfortable with hitting right up against your 300W barrier.
That should be able to max out pretty much anything at 1080p though. (with a GTX 1060)
I also included a 80+ Gold power supply so that less power is wasted in the AC to DC power conversion.
You can always buy a killawatt meter if you want to take more accurate measurements.
80ºC is acceptable for nvidia. Little on the warm side but still acceptable.
Something you could check is if your psu is providing enough wattage to support the demands of your pc hardware by using a wattage meter.
Buying one from amazon isn't a terribly expensive considering the benefits.
I dont see how a brand new evga graphics card could be faulty. I own close to two dozen evga graphics cards and every one of them has been flawless.
I'm more inclined to want to measure the wattage demands under full gpu load. 550 watt power supply should be adequate however every pc is different despite what's estimated on pcpartpicker as an estimate.
Old stock or just old power supplies the capacitors degrade with age and can provide less wattage and be incapable of providing stable power delivery. If your power supply tops out at 350 watts on a watt meter with your GPU and cpu running at maximum load it's possibly faulty and 350 watts is definitely inadequate to run a 1080 and the rest of your pc components.
Often when your considering power supplies it's very wise to check reviews or info from jonnyguru or his forums.
What i see based on this is that antec power supply design is quite old. PC power supply ATX component standards have updated in 8 to 10 years.
Compared to a new design manufactured within the past two years that has a near flawless review.
Generational compatibility of pc components can make a difference with system performance and stability due to component manufacturing standards such as the ATX power supply design specifications.
The meek nerds on buildapc and pcmasterrace commonly recommend obsolete power supply designs due to peer recommendations and often not based on specifications so be wary of that issue.
Kill A Watt
You're better off using a physical power meter like the Kill-a-watt.
For an exact measure get a KillaWatt device
For getting an estimate, others have provided software that could do it like HWMonitor
Something like this.
I just used one of these.
It was pulling .21 Amps at 120 volts. Not .21 Watts.
Yes. Something like this is how you test and check the power draw. Check it for a few hours.
its a wattage monitor.
It is a opportunity to maybe make some extra money.
If you rent out a kill-a-watt for $1^99 per day, and the customer finds out his entertainment centre has a noticeable phantom load, even when in the "off" position (and/or too many 'on/off' switches for their liking), you could sell them a switched power strip with a few dollars markup (right then, right there, as it saves them the fuel on a hardware-store trip).
If, using a few thermometers, you can show there is a temperature loss in the hot water pipes (and how much energy that costs during the next 25 years), you might get the job right then, right there, (if you 'just happen to have' those insulating sleeves in your car, else they might google-fu for the cheapest bidder).
I'm not saying you should (heavily) invest in equipment/material, just study it and (possibly) bring it up with potential customers (if for no other reason than to make them aware it exists and that there are solutions).
Even if the customer does not select you for 'the works', they still might hire you as 'knowledgeable independent specialist' to look at other offers, or (using a rented thermal camera), verify 'the works' by another contractor has been done properly.
Something like this
kill a watt
Computers don't draw the amount of power the PSU is rated at. There is a tool called a clamp meter that can calculate the power used.
They also produce idiot proof versions like this.
where do you roast? My house is crazy old and the garage is detached and has it's own fuse box so I knew it would not be perfect. I suppose if you are living in a more modern place, the power should not be an issue. Do you have a multimeter? they are super cheap on eBay, or whatever the equivalent to Radio Shack is. I googled how to do it before I went and rammed things into a socket. But it was immediately evident that instead of the 120v I needed, I was running at 110-113. There seems to be a lot of debate as to whether that matters and most homes run less than 120 (some run higher) but I know, that the 10% power loss I was experiencing was enough to make the difference. I am still learning and not all my roasts are great and I should probably start logging what I do, but now that I can dial in the power it at least eliminates that variable from the equation.
variac and this so an extra $130 expense...but, for me, worth it. Check your power first before investing though. good luck!
Hack one of (these) and send the digital data to your favorite hobby microcontroller. Arduino?
Raspberry Pi, Arduino, Kill A Watt energy meter