People thinking that they are saving money from more energy efficient products

[mikeo01]

Until there is evidence of an intergalactic pink star-banana which shed seeds onto the planet to create the trees, I won't believe that either.

I believe evidence to simply be a perception of human understanding. Evidence isn't evidence because man-made is simply that; man-made. Course it'll give out results because we can only perceive things in a human way.

Just like we haven't a clue how the majority of all life on earth works because we are trying to understand things non-human.


But yes agree to disagree, I simply think humans are silly trying to solve or understand everything outside their own realm.

[peterb]

I don't buy the theory of side effects. For example, the heat generated through my modem is wasted because it's not controllable. I can't turn off the heat during summer, when I go out or go to bed. Heat generated through electricity is expensive compared to heat generated through my central heating which is two-thirds cheaper and more controllable.

I deliberately left out the type of energy - but you are quite right in that gas is cheaper and a more efficient way of heating a home. It takes roughly 2.5 times the amount of thermal energy at source to reproduce electricity. ie, for a 1Kw electric fire running for an hour 91KWh) it takes about 2,5Kwh of gas to produce it - possibly more taking into account transmission losses. That is a basic thermodynamic law based on the thermal cycle of converting chemical energy into mechanical energy into electrical energy. (oogle Carniot cycle or Rankine cycle for a detailed mathematical explanation.

But it is undeniable that every Kwh of electrical energy that enters your home ends up as heat and raises the ambient temperature, and therfore may result in a corresponding decrease in the use of direct heating. So if you reduce the electrical energy input, you may end up using more energy for direct heating.

So to use your Maplin energy meter to its full extent, you should be measuring the amount of gas consumed, by reading your gas meter, or unless you have a modern boiler with a modulating burner, you could put an elapsed time meter on the boiler gas solenoid and measure the time the boiler is producing heat. (If you cook useing gas, that gas cooker is also contributing to the ambient heating of your house, as does an electric cooker).

And while your energy meter might be reasonably useful in estimating the power consumption of a single device, you would get a better picture of your energy use by reading your gas and electricity meters every (say) week, and calculating your total energy use, and then see what difference using lower power devices makes.

But you really need to do that over a long period of time because unless your house is really well insulated, the ambient outside temperature will almost certainly have a greater effect on the heat loss from your house, and the energy requirement to compensate for that loss to maintain a comfortable living environment.

[DanceswithUnix]

I have a couple of energy meters, and the Maplin is the better of the two. But still I am finding it less and less useful as at low power levels I just can't trust it.

If I plug in a desk lamp, then I can put in an old 40W or 60W bulb and the reading is close enough to the bulb rating. If I put an LED or florescent bulb in though, then it the reading goes up when I turn it on but not by the 6 or 7W rating of the bulb. So I figure it is always a few watts out, which on my server that it is currently plugged into where it reads a steady 58W then that is under 10%, but on something like an access point that only draws about 5W a few watts out is a massive percentage. Sometimes with nothing plugged in it will read a few watts power draw, but not always. I presume that is down to some sort of self calibrate/tare facility so perhaps I need to be far more strict on how I deploy the thing.

I do find it useful for deltas though, eg without the kid's minecraft servers running my home server takes 53W, so minecraft is costing me about 2.5W per instance when no-one is logged in. It can go up when they start blowing the game's landscape up with TNT, but that is transient so I don't worry about that

[DanceswithUnix]

I simply think humans are silly trying to solve or understand everything outside their own realm.

People are curious and want to understand, you can't stop that. I find it sad when they resort to crystals and pyramid power, but that shows that even in a vacuum of knowledge there is a desire to make sense of stuff.

As a complete aside, there will come a time when your sig will stop working, you will need to upgrade it to an IPv6 compliant "There is no place like ::1"?

[peterb]

I have a couple of energy meters, and the Maplin is the better of the two. But still I am finding it less and less useful as at low power levels I just can't trust it.

If I plug in a desk lamp, then I can put in an old 40W or 60W bulb and the reading is close enough to the bulb rating. If I put an LED or florescent bulb in though, then it the reading goes up when I turn it on but not by the 6 or 7W rating of the bulb. So I figure it is always a few watts out, which on my server that it is currently plugged into where it reads a steady 58W then that is under 10%, but on something like an access point that only draws about 5W a few watts out is a massive percentage. Sometimes with nothing plugged in it will read a few watts power draw, but not always. I presume that is down to some sort of self calibrate/tare facility so perhaps I need to be far more strict on how I deploy the thing.

I do find it useful for deltas though, eg without the kid's minecraft servers running my home server takes 53W, so minecraft is costing me about 2.5W per instance when no-one is logged in. It can go up when they start blowing the game's landscape up with TNT, but that is transient so I don't worry about that

I'm not sure that the cheaper ones take into account true mains voltage, I think some just assume a nominal value. and if they just measure current, they are not measuring true power if they are connected to a reactive load, but will be calculating VA. I would expect a CFL, with its control gear, to have a higher reactive component than a purely resistive load like an incandescent lamp.

Some plug in power meters do present a reading for VA and that implies some phase measurement, but in a low cost instrument, I'd question the absolute accuracy of that, especially if the waveform is not truly sinusoidal, but has a high harmonic content, which is often the case when the load is a switching regulator.

[DanceswithUnix]

I'm not sure that the cheaper ones take into account true mains voltage, I think some just assume a nominal value. and if they just measure current, they are not measuring true power if they are connected to a reactive load, but will be calculating VA. I would expect a CFL, with its control gear, to have a higher reactive component than a purely resistive load like an incandescent lamp.

Some plug in power meters do present a reading for VA and that implies some phase measurement, but in a low cost instrument, I'd question the absolute accuracy of that, especially if the waveform is not truly sinusoidal, but has a high harmonic content, which is often the case when the load is a switching regulator.

The Maplin one I have gives you a choice of VA or Watts and ISTR will tell you the power factor. So yes it has some idea of what it going on, but proper power meters cost thousands and this one costs £20 unless you get it on a good offer like I did. So hence it isn't miles out, but a cheap device designed to work from 0 to 3000W it is reasonable to expect it to be +/- 5W, which on a modern 5W load isn't helpful.

Most of my usage is "does this improve things", so for a relative measurement like that it works well. I just take the absolute value with some salty pinches.

Edit to add: Looks like they still sell the one I use: http://www.maplin.co.uk/p/15a-plug-i...-monitor-l61aq

[TheAnimus]

So many of those monitors have terrible reviews:

http://www.maplin.co.uk/c/batteries-...aving-monitors

It's funny, it's something that's never really bothered me, as the cost of an accurate enough meter, would probably negate the saving. My PC is not only left running almost 24/7, but the UPS is most definitely too.

I am not sure I would ever trust the majority of these cheap meters to say faithfully measure the quiescent load of my wireless charging pillow for my phone

Peterb, do you happen to be familiar with the official electric meters process? Are they still just simple electromagnets turning cogs due to the hot wires current draw?

[Top_gun]

But it is undeniable that every Kwh of electrical energy that enters your home ends up as heat and raises the ambient temperature, and therfore may result in a corresponding decrease in the use of direct heating. So if you reduce the electrical energy input, you may end up using more energy for direct heating..

I very much doubt this electrical waste provides meaningful ambient heat. Try switching off your central heating and see how far you get on a cold winter day!

It's far more cost effective to replace or turn off the inefficient energy device and then use the money saved towards the fuel for central heating, a much cheaper way of providing heat.

I have a couple of energy meters, and the Maplin is the better of the two. But still I am finding it less and less useful as at low power levels I just can't trust it.

I deliberately avoided that particular model because of its inability to measure small amount of wattages. So a few years ago I chose a recommended model which is accurate to within 0.1 watts according to this review link.

http://www.earth.org.uk/note-on-plug...UK-REVIEW.html

It seems remarkably accurate when I test the item in my own home.

Thanks for sharing your concern but really it wasn't needed in my case, chaps!

[CAT-THE-FIFTH]

my wireless charging pillow for my phone

I thought you were joking for a minute.

You were not!!

http://www.microsoft.com/en-gb/mobile/accessory/dt-901/

[TheAnimus]

I thought you were joking for a minute.

You were not!!

http://www.microsoft.com/en-gb/mobile/accessory/dt-901/

Yup I got one free from an event a while back. I've got 3 wireless chargers now. I really want the car holder one. I just like the idea of slam, phone in holder, no messing about plugging the wire in, think how much better my life would be?

It does remind me of Charlie Brooker, back when his writing was funny, reviewing the iPhone 4, and describing the proper usage so as for it to not drop signal:
http://www.theguardian.com/commentis...ne-4-apple-new

[Rens11]

I use this logic when explaining the constant GPU upgrades to the MRS.

[Butuz]

http://forums.hexus.net/psus/314477-...ml#post3198149

[CAT-THE-FIFTH]

LOL,on OcUK some poor chap was asking whether a R9 290 if reduced to £200 in the store,would be worth it over a £260 GTX970. One of the long serving members said the GTX970 was worth it in primary order for the lower power consumption...!

Had to go on and tell the chap how much money he would be saving each year in lower power consumption,which was not really worth a potential £60 upfront saving if power consumption was included as a major factor,plus additional money(around £20 to £30) from the game bundle.

[watercooled]

So many of those monitors have terrible reviews:

http://www.maplin.co.uk/c/batteries-...aving-monitors

It's funny, it's something that's never really bothered me, as the cost of an accurate enough meter, would probably negate the saving. My PC is not only left running almost 24/7, but the UPS is most definitely too.

I am not sure I would ever trust the majority of these cheap meters to say faithfully measure the quiescent load of my wireless charging pillow for my phone

Peterb, do you happen to be familiar with the official electric meters process? Are they still just simple electromagnets turning cogs due to the hot wires current draw?

Most of the recently-installed meters I've seen have been solid-state models; there are probably still a load of electromechanical ones out there but they tend to lose accuracy (measure low due to e.g. increased friction) over time so many are in the process of being replaced. In terms of accuracy, AFAIK the solid-state ones are superior, and work by sampling and comparing the current and voltage waveforms. Interestingly it seems many of them use FeRAM for their non-volatile backup. The reports of 'poor' accuracy on these meters, in many cases, might just be because customers were previously being undercharged.

Those clamp-on meters however can be catastrophically inaccurate. All they're able to do is measure the current waveform and assume the voltage is fixed and in-phase. The worrying thing is, I seem to remember some companies accepting those measurements for billing. One can only hope it was at least compared against an average PF and only used for interim measurements, with 'proper' measurements still occurring on occasion.

I'm not too sure about the plug-in meters in general, but I know the one I have only has 1W resolution, and can read low at least for fairly low loads. E.g. some DC-side of PSU measurements (which are likely to be quite accurate) come out higher than the AC power reported by that meter, even taking rounding into account.

[Zak33]

With reference to the back ground heat from electrical equipment either positively improving heating bills or being uncontrolled and worthless - when I had two dogs they slept in my computer room at night . I'm winter I ran my laptop over night FOLDING@ HOME to warm their room. I didn't turn on the gas cental heating and warm the entire house or go round adjusting all the radiator valves every night and morning to just warm their room. It worked . Cost little. Was effective.
When we watch a film on our projector in autumn / winter we turn off the central heating early in the evening knowing the film watching will warm that room!

With good insulation..I don't grumble about light bulbs being left on or the TV still being on over the cold winter months. The heat is fairly well retained in my house.

[wasabi]

Graphics cards are an interesting issue because they're an interesting exercise in understanding the difference between maximum, mean, median and mode current draw. Peak, sleep mode, how it behaves when just web browsing, how it behaves in SLI, all important issues.