Original URL: https://www.theregister.co.uk/2012/06/29/energy_saving_trust_report/

War On Standby: Do the figures actually stack up?

Will you stop turning the TV off at the wall

By Lewis Page

Posted in Science, 29th June 2012 12:00 GMT

Analysis The War On Standby rumbles on: this week, courtesy of the UK government and "third sector" quangocracy, we heard yet again that gadgets left on standby suck vast, planet-wrecking, expensive amounts of energy from our electricity sockets.

It's an idea which has gained a lot of traction over the years. Many Reg readers (and hacks) nowadays find themselves continually nagged by persons of significance in their lives to the effect that they should be turning such things as TVs, games consoles and computers entirely off rather than leaving them on standby - or even unplugging them or switching them off at the wall when not in use. One of the great achievements of the human race - namely remote control, in particular the ability to walk into a room, flop or sit down, press a button of some sort and cause one's technology to spring to life without any fiddling about - is apparently too expensive and damaging to be permitted.

Meanwhile, curiously, it appears that such things as regular showers, hot drinks and food (previously refrigerated), powerful hair-furtling appliances, clothes and bedding laundered at frequent intervals, heating kept on at high levels throughout the winter etc etc; these are all inalienable human rights.

Does any of this make sense?

On the face of it, maybe so. No less a body than the Energy Saving Trust - a government funded, tax-free quango which also sells consultancy to business, and is warmly endorsed by Friends of the Earth - has just come out with a study of domestic energy use in the UK, which it carried out in cooperation with two government ministries: the Department for Energy and Climate Change and the Department for Environment, Food and Rural Affairs. In it, we learn that a normal UK household can be leeched to the tune of a thumping 600 kilowatt-hours (kWh) of 'leccy by kit left on standby in just one year - which could add £90 to the bill.

That's serious: let's have a look at the EST report (pdf). From it we learn that total draw from standby power in a house is at the lowest 47 watts, at the highest 81 watts. If you assume that consumption 20 hours a day, the high number gives you your 90 quid.

We know this because:

Consumer electronics and computer products were monitored continually with special software that could tease out of the wattmeter data the standby power and rate. Two types of standby power were measured: a minimum average value of standby and a maximum average standby power consumption. Details of how these two were measured can be found in the full report.

In fact the EST report is merely a dumbed-down version of the proper report, which we can read courtesy of DEFRA here (also pdf). We find that the study was carried out on a rather small group of households - just 11 houses were monitored continuously for a year, though others were monitored for a single month so that for each month of the study there were thirty-odd households being monitored; all occupied by the owners as no rental homes were included.

But what about this mysterious software which can tell when devices are on standby and accurately say how much power they use? How did we arrive at these very large amounts of power on standby? Because they are very large. Modern tellies use less than a watt of juice on standby - the latest ones less than a tenth of a watt. There are rogue 10W+ set-top boxes etc out there, but you'd need several duff gadgets at least to get up to 47 watts, let alone 81 - and it can't be the case that the average household contains several such dodgy devices and leaves them on 24/7 when not in use.

So what are the figures based on?

We are told:

The implemented in-situ measurements included monitoring of the household general energy consumption, as well as measuring the different appliances in the household. In most of the households, audiovisual and computer sites (which are the main sources [sic] of standby power in households) were continuously monitored with plug-in wattmeters. Using special software, it was possible to extract from the monitoring data all the standby power and the standby rate.

The "sites" include all the ancillary bits of kit as well as the main one: ie the AV site includes not just the telly but set-top boxes/DVRs, disc player etc. The computer site includes attached monitors, speakers, the modem/router, printer and so on.

The "low" figure of 47 Watts total standby power, we are informed, is calculated by adding up all the different bits of kit's individual consumption while on standby and averaging across the sampled households.

Getting into detail, the report says that the typical AV site on standby consumes 17.8 watts and the computer site 9.3 Watts: total 27.1 Watts, barely over half the 47-watt total. So even by the report's figures, it would seem that actually there must be some major standby villains in the home apart from gadgetry.

And frankly, delving further, the "special software" which can "tease out" the standby power would appear to produce erratic results to say the least of it. For instance, two appliances listed as "Aerials" were monitored during the study (one must assume that these were boosted aerials, as they were plugged in to power sockets).

Information on power consumption by 'Aerials' uncovered by the government and the Energy Saving Trust. Credit: DEFRA/DECC/EST

Aerials: The shocking truth. We never switch them on, therefore they are on 'standby' almost all the time. But if we did switch them on they would use no power!

According to the "special software", "Aerials" use zero watts when switched on - which they never were during the entire study period, apparently. But they were "on standby" for no less than 88 per cent of the time monitored, drawing 3.2 watts average. This is plainly bunk. They were simply on: but the software wasn't capable of detecting the fact.

Nobody ever has any kit turned on from 0300 to 0400

Running through some of the other kinds of appliance we see some other curious results. "Modems" in the study were "on standby" drawing 10 watts no less than 79 per cent of the time they were monitored. "Speakers" spent 32 per cent of their time on standby. Etc, etc.

It's plain that a lot of the time the software was assessing things as being on standby when they were actually on and working. Furthermore, the software also seriously contradicts the idea that one can assume (as the Energy Saving Trust figures do) that standby power (as determined by the software) is consumed by devices 20 hours a day. Looking at the figures for the "sites" and individual appliances, it's plain that the software assessed that even kit which had standby modes was switched off much of the time when not in use, as well as sometimes being put on standby.

It's plain that the Energy Saving Trust either didn't read the full report, or didn't understand it.

So we can disregard the 47-watt figure and the lower annual standby consumption estimate from the EST: it was utter bunk to start with, and then was interpreted by the EST in a way which contradicted everything the full study said!

OK, what about the high 81-watt total-standby-power-inna-house estimate, the one which produced the headlining £90 annual figure? Where did that come from?

This was produced by measuring the total electric power draw by the study houses between 0300 and 0400 and subtracting comsumption by appliances assessed as being probably "on" at that time - mainly fridges - then assuming that all the rest of the power coming in through the meter was being drawn by kit on standby. We are blithely told:

Energy use during the night exists in all types of households. It is unlikely that this consumption could be entirely due to night users but is, more probably, due to standby consumption.

This despite the fact that over a quarter of the sampled households were "multiple person households with no dependent children" - the kind in which young night-bird adults live. And indeed the full report includes many graphs confirming that even in the view of the a-bit-special software plenty of the power draw from 0300 to 0400 is not attributable to standby consumption. And we must again remember that far from being left on "standby" 20 hours a day, the special software assures us that the kit in the study was often switched completely off.

So that figure is bunk, too. As is the 600 kWh and 90 quid derived from it. To be fair the EST consultant Paula Owen, drafting the "summary" report, sort of admits as much:

Due to the nature of the monitoring, and the quantity and complexity of unpicking each appliance’s power-use pattern, we cannot at this point ascertain exactly for how long the standby consumption is present. These current figures should be seen as a best estimate until further research can be carried out.

No they shouldn't: they should be thrown in the bin. They are based on rubbish - the data set from the full report is very small to begin with and amazingly badly tabulated. TV signal boosters are recorded variously as "Aerials" and "Boosters", we find a batch of "Xboxes" of unspecified model and then some noted as "Xbox 360s", separate "Modems" and "Routers" - almost all of which were most likely combination boxes - etc etc.

And we can forget the idea that this study tells us gadget power consumption is up, too. Even Owen writes:

The surprise here is the smaller contribution of consumer electronics compared with [previous figures]. Entertainment products fall from first to third place. However, if combined with the ICT sector, which is increasingly the case with the continuing convergence of these product types, these two sectors make up 25 per cent of the total [down from 33!] ...

The breakdown of where electricity demand comes from offers some surprises. Consumer electronic devices do not seem to be increasing their ‘market share’ of electricity consumption at the rate previously estimated ... Refrigeration and lighting are still the highest consuming product groups.

Of course this study was so shoddily carried out that it doesn't really tell us anything. But if it does, it tells us that gadgets - and in particular, gadgets on standby - just aren't a big issue in terms of electricity bills or carbon emissions.

If Owen had wanted to try and extract something useful she might have chosen instead to look at things like this in the full report:

It is notable that lighting consumption during the night occurred in all types of household. It is unlikely that this consumption could be entirely due to night time uses such as getting up to use the bathroom. It was not possible in this case to identify the lights that were responsible for the night consumption.

Of course people do leave lights on at night! But actually there's a tendency for inexpensive modern lighting to use shoddy power bricks which suck a lot of juice even when the light is switched off. This was noticed by rather more serious power researchers quite a long time ago, but if the EST wanted to give some good advice they would tell us either not to buy cheap lights with power bricks or to turn them off at the wall - as opposed to the inoffensive new telly with its 0.1-watt standby draw.*

But the fact is, it's not really domestic 'leccy that's the main issue, if you worry about energy use and associated carbon emissions. Nor is it much to do with food.

Whenever an eco-activist starts going on about gadgets or electricity or food, ignore them. The big stuff is travel, making and having things (ie buildings, furniture, tools, interior decor, infrastructure etc) and heating/cooling (a large amount of this is laundry and personal hygiene).

Remember: skipping one bath or shower saves as much energy as switching off a typical gadget at the wall for a year.

And also remember: If you see a news report on energy which cites the Energy Saving Trust or the consultants and contractors who prepared the reports - it's pretty safe to ignore it. ®


*The paragraph quoted above refers to ceiling lights powered from 5A lighting circuits, not ones plugged into the wall: but these often use transformers too - for instance for low-voltage ceiling spotlights. In such cases, of course, it is often not feasible to cut power to the transformer without knocking off a breaker or pulling out the light fitting. It's odd that the very people so keen to unplug the telly are often big fans of such spotlights, and would never believe that they waste far more juice even when switched "off" than the TV does on standby.