Energy Saving - the great standby fallacy

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Gulliver

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Lots of sources will tell you that there are huge energy losses when electrical items are on standby. I have heard it quoted that items (e.g. TVs) on standby use 1/3 of the energy of full operation. The UK government is reported to be about to legislate to remove the standby facility in future.

Here are the facts. My family averages 17.75 KWh per day according to my latest ESB bill. My TV (Pioneer 43") consumes 287w in full operation, and 0.4w in standby. If we assume 21hrs standby each day, then the equation for a 24hour period becomes:-
21 x 0.4 = 8.4w in standby
3 x 287 = 861w in operation​
So standby represents less than 1% of the energy used by the TV.
And standby represents .047 of 1% of the family's usage of electricity. In other words, I would have to have 21 similar devices on before standby would consume 1% of the family's usage.

If we expressed standby as a percentage of the total family usage of energy (heating oil, petrol, electricity) then standby is an even smaller percentage.

And what behaviour change would the removal of standby induce? I believe that we might leave the TV on for a minute or two more on average, since we have to get up from the couch to turn it off. Two minutes of extra TV would result in an overall higher energy usage.

I have checked other devices in the house, and the results are similar.

Someone in authority needs to get the facts straight.
 
Nope, Clubman

If you want to express them as KWh then they would read:-

21 x 0.0004 = .0084KWh

The figures in the original posting are correct
 
Clubman - I read the detailed specification - but if you really want to double check, I have the metering equipment with which I can check it precisely
 
I have often wondered about all the fuss made of turning off lights and electrical devices. Does the law of conservation of energy have any practical meaning in a domestic setting? It seems to me that most of the energy from a light bulb is in the form of heat, so it isn't really going to waste, just because you are not there to see it: - it is still (slightly) warming the room.

It seems to me that by far and away the two biggest things we can do to stop 'wasting' energy are:

1. building with better insulation and
2. the simple act of wearing a jumper indoors and turning down the thermostat.

I am not that old, and I can still remember frost on the inside of the window panes. Didn't do us any harm at all.
 
The use of energy saving lighting and controls offers the best savings in terms of energy consumption in an office or commercial environment for the simple reason that unwanted heat produced by lighting places an extra burden on the air handling/ cooling equipment required in those types of buildings. I'm sure that more modern appliances use less power on standby now than they did some years ago,but nonetheless I don't like to see appliances in standby mode at home when they are not being used.
I agree with MOB more insulation and turning down the thermostat are two of the most effective ways to conserve energy. Also the use of more efficient boilers and "A" appliances in the home should be considered. We are still putting a lot of quite innefficient oil burners into our new homes, at the very least we should be looking at condensing models or models that will run on biofuel. I really want to "believe" in CFL bulbs but I've had 3 or 4 of these "blow" on me at home after very little service (less than a 100 hours?). Conventional wisdom seems to suggest they are most suited for applications where lighting is left on continuously or for long periods without switching.
 
Is the message being conveyed by the 'power of one' campaign being missed here? It's not what one person or household can save but it's the effect achieved when a small saving is multiplied by for example the number of households in the country.

My pet hate is the number of lights that are left on inside or outside houses at night. Just as an example, 100W x 10hr = 1Kw x 1M households = 100Mw if my wonky maths are right. I'm not remotely against using lights overnight, but a PIR doesn't cost much and will make a huge difference to an outside light and low-energy bulbs etc will help inside.

Curiously, the 'power of one' website claims a saving of 20% if appliances are not left on standby. Do older TVs (still in the majority I'd say) use significantly more power on standby? What about stereo systems, computers, radios, microwaves, ovens, electric clocks, power-sockets and bars with indicators etc etc?
 
I don't know if you guys watched Dragon's Den on BBC2 last Tuesday night, there was an hitherto unheard of situation whereby all the dragons invested in an invention, two guys had come up with a system, (using a simple microporcessor to read then store the signal frequency of your remote), such that when you placed the tv/box-set into standby, from the comfort of your armchair, the chip would cut the power to the appliance. According to these guys certain box-sets consume the same amount of energy in standby as in 'on' mode.

I reckon we'll be hearing more about it in the coming months.

ALERT.
 
Problem with generalisation about standby energy consumptin is that it depends on the specific device you are talking about.
 
alert said:
According to these guys certain box-sets consume the same amount of energy in standby as in 'on' mode.
Click to expand...

Sky digi boxes are always on, so they can load software updates and have instant up to date program listings. When in standby more they just shut down the RF and Video outputs.

Towger
 
Carpenter said:
I really want to "believe" in CFL bulbs but I've had 3 or 4 of these "blow" on me at home after very little service (less than a 100 hours?). Conventional wisdom seems to suggest they are most suited for applications where lighting is left on continuously or for long periods without switching.
Click to expand...
I've had similar problems with CFLs. AFAIK they have only so many on/off's before they blow so are not ideal in every situation. I think I read some nonsense idea recently about banning or putting extra tax on the standard light bulb.
 
so it isn't really going to waste, just because you are not there to see it: - it is still (slightly) warming the room.
Click to expand...

It might be slightly warming the room, but it's doing it very inefficiently. It would be a very expensive way to heat your house.
 
MOB said:
It seems to me that by far and away the two biggest things we can do to stop 'wasting' energy are:

1. building with better insulation and
2. the simple act of wearing a jumper indoors and turning down the thermostat.
Click to expand...
Indeed.
Hidden electrical bandits

Things that use electricity even when they're off

Most people waste so much energy that they don't need to worry about this section -- they'll get LOTS more benefit by insulating, using the AC less, installing ceiling fans, using compact fluorescent lights, and turning out lights when they're not using them.
Click to expand...
As ever it probably makes sense to concentrate on the things that give the biggest bang for one's buck first. However usually it's not much hassle to also deal with some of the smaller things such as switching off devices rather than leaving them on standby so why not do it?
 
I don't see why like a computer like powersaving can't be in more everyday devices like water heater immersions etc. I mean if you leave a immersion on for over 3 hrs its obviously by accident. I'm sure theres other things aswell. Kettle with no water. How about devices that have no human activity for hours VCRs, DVD/HD recorders. They should automatically go into powersaving. Most don't.

I'm driven mad with heating systems. Quite often the thermostats setting have no real effect other than off/on switches. On a hot day the heating will still come on. Seems to be a common problem.
 
aircobra19 said:
I mean if you leave a immersion on for over 3 hrs its obviously by accident. I'm sure theres other things aswell. Kettle with no water.
I'm driven mad with heating systems. Quite often the thermostats setting have no real effect other than off/on switches. On a hot day the heating will still come on. Seems to be a common problem.
Click to expand...

Immersions do have a cut-off thermostat, which is accessible when you remove the cover. So if you do leave the immersion on accidentally (presuming it is not faulty or set too high) it will cut out once the set temperature has been reached. There's also the additional option of fitting a timer control. Most newer kettles feature a "boil dry" automatic cut-off device which is designed to protect the appliance, mainly.

This is not a personal comment but in my experience most problems with heating systems that do not perform as expected can be attributed to either of two things: improper use of the existing controls (through ignorance of the user) or faulty controls/ poor design or installation. A little basic knowledge about the simple functions of TRVS, room stats and motorised valves are central to understanding how to use our heating systems most effectively.
 
Back to the start of the thread - I agree with turning off lights. I agree with insulation. I agree with any form of genuine energy saving.

But I detest being bullied by false information. We are being sold a lie in the debate about standby. I have checked the numbers, believe me. Modern TV, DVD, HiFi, etc. uses an infinitesmal amount of energy in standby. Less than 4 kwh if my 43" TV was on standby 24x365 for a full year. Less than 1/10th of the smallest CFL bulb.

Removing standby from these items will not save a significant amount of electricity - even when applied to the whole population. It's a myth, a fallacy.
 
Gulliver said:
It's a myth, a fallacy.
Click to expand...
Perhaps it's an over simplification or a case of "gilding the lily" but I think the campaigns do help to raise the collective awareness about energy use- why have something on standby mode unless it's necessary, why leave lights on unnecessarily? There are a great many people who don't care about energy use at all.
 
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