Energy monitors – spend a little to save a lot?

Maybe useful in tracking down unusual or seemingly high electricity usage , but for most people reading the meter everyday for a week or so should give the same information.
Anyway for many its the gas fired heating which is the prime candidate for making savings on.

We recently acquired free of charge from Npower the Efergy Elite energy monitor, a Which Best Buy. It has already saved us hundreds of pounds per year.

Early one morning a few weeks ago my wife and I removed all the fuses in our house, replaced them one by one and religiously tested how much power each appliance actually uses, storing the results on a spreadsheet, so that we were made totally aware the impact each appliance makes.

But when we inserted the lighting fuse we noticed an immediate usage of 150 watts even though there were no lights switched on inside or outside the house. After a long investigation we found a light switch in our garage that is attached to a redundant fluorescent fitting with no bulb! When the switch was on it used 150 watts even though there has been no bulb for at least 10 years. The power was leaking away through the old lamp starter circuit (and this can happen even on a working lamp). 150 watts on my tariff costs £170 per year so could have cost us the equivalent of £1700 over the last 10 years!

Needless to say all my strip lights have now been replaced with energy saving lamps.

I believe one of the benefits of an Energy Monitor is to show you how much energy you use when appliances are on standby, say, during the night, as this is a constant drain 24 hours per day, 365 days per year. By concentrating hard on which items can be switched off and not just left on standby we have been able to reduce our overall consumption by around another 100 watts per hour, or £113 per year (and this is while we are asleep)

If you can be bothered putting in the time & effort using an Energy Monitor it will pay you back handsomely.

I’ve had an energy monitor for about 2 and half years now.
It’s actually pretty useless really if you are willing to put in the effort that rarrar and Colin (above) and I already have done: Every appliance has a rating shown on it. This is usually quite easy to find. If you know the rating then you can set up a spreadsheet like Colin refers to. I did this about 7 years ago when I was looking at whether Economy 7 would save me money.

If you simply pull out the plug of all appliances when they are not in use, and certainly before you go to bed or go out, leaving only things like the fridge, freezer, VCR or DVD recorder (if you have it set to record), aquarium (if you have one) and electric clocks (if you have any mains ones) then you have no interest in standby usage and are guaranteed not to consume more than you expected on standby. You also reduce by a vast amount the risk of fire in your home. (In fact most of my appliances are so old that they don’t even have standby so for people like me pulling the plug is a matter of routine and nothing new to get used to).

If, like Colin, you have a redundant appliance or fitting (like his garage light) you should have it permanently unplugged or disconnected for safety. Colin’s light fitting must have had a major fault to earth to use 150 watts with no tube in (I am qualified in this area, I’m not just making this up) so in fact it posed a shock (and possibly fire) hazard for all that time it had been left on. However, identifying such unknown faults is one GOOD use for an energy monitor and if, like Colin, it prompts you to get the fault rectified, it may also be a life saver.

Reading your meter regularly (like Rarrar suggests) is also very effective. This is also usefuk in identifying a meter fault: meters DO read “fast” and “slow” sometimes and they DO go faulty. Your energy monitor won’t show you that but regular meter readings will draw this to your attention. You can then get the electricity company out to replace the meter. (And this is worth doing even if the meter is reading “slow” and you are being UNDER charged, because if the energy company finds out about the fault later, they will estimate how long it’s been faulty for and expect you to pay up for the estimated extra energy you’ve used over what it said. Legally you have to pay at least some portion of this, even if you try a court battle first, so it’s in your interests to have an accurate meter at all times.)

In my case I set up my spreadsheet and read my meter at 11:30 p.m. and again at 7:30 a.m. every day for 6 months (spanning Jan to June one year) to see if I would benefit from Economy 7. My “base load” is around 450 watts because there is a fridge, freezer, aquarium and three ponds with filtration which are running 24/7. At the time of my experiment it was as broad as it was long to have E7, so I didn’t bother changing.

I bought my energy monitor just after buying a washer which was supposed to be energy saving trust recommended: it very quickly became apparent that my 25 year old machine had been using much much much less than a quarter of the electricity hat they new “energy efficient” one did. I bought the monitor to assist in a battle with trading standards, the manufacturer of the washer and the Energy Saving Trust, which resulted in the EST admitting that they knew that all new washers, and other new appliances, use more energy than their old counterparts, but they (the EST) only test agains other current machines not against old models. My Energy monitor therefore helped me to extract this admission from EST but the manufacturer still refused to offer any support so the new washer was sent to scrap and a reconditioned very old one bought which uses less power.

This leads me to one final point: keep old appliances until they are no longer serviceable: new ones may come with green claims but as you can see from the EST’s admission to me, these claims are not always what you might assume them to be.

So, in summary, I think energy monitors are only really of any use to people who don’t actually know how to read a meter and / or don’t really know what their appliances are rated at.

I haven’t bought an energy monitor because I am very sceptical about the practicalities of its use. I have tried to quantify the issue for my home by doing a quick count of the energy using devices. The totals came to:-
41 independently switched lights
22 permanently wired devices
40 devices permanently plugged in
23 devices plugged in occasionally

This is only the start of the problem. Most of the devices will have multiple modes of operation, many of them not under direct user control. A few examples are:-
• A washer/drier with 20 programmes, 12 of which I have used. Most of these programmes have multiple phases. There are also 5 independent buttons that control global modifications to some of the programmes.
• Fridges and freezers that may or may not have their compressors running at any one time. This will depend on such things as the ambient temperature, whether fresh food has been put into them, and whether the fast freeze button has been pressed.
• Chargers for rechargeable devices that detect when the device is fully charged.
• Central heating systems where the pump and 3 way valve will operate according to demand.
• TVs that vary their screen brightness according to the ambient light.
• PCs and all-in-one printers that vary their consumption depending on which components are active at any one time.
• Devices which have a standby mode, or perhaps more than one stage of standby. Some devices with an on/off switch will also use power in the off mode unless they are switched off at the mains.
• Toasters that use different amounts of power depending on how many slots are in use.

There will also be an annual churn of devices and light bulbs, as they either come to the end of their natural lives or when new types of device come along.

I know our household size (4) is larger than the average (2.4) and also our house is larger than average (a 5 bedroom semi). However, the figures still suggest that the average household would have to undertake a large programme of controlled experiments if they were to try to calibrate each device. The person doing the testing is unlikely to increase their popularity with other household members, given the disruption all this would cause.

I can’t help feeling that the current style of energy monitor is best suited to a person living alone in a small flat and with a lot of time on their hands.

Energy monitors are helpful when you first obtain them. We found the halogen lights to be the biggest user of electricity. Three rooms each with a minimum of 3 x 50watts really crank up the wattage and you never give it a thought. We are now trying to purchase some new low wattage versions that give the same light but use less electricity but they aren’t easy to find and can be very expensive. Also we are looking (unsuccessfully) for the plugs into which you can place individual appliances to check their usage. Again, these have been ‘out of stock’ on many web sites for months and months. So, monitors can be useful appliances but trying to solve the issues raised can be fraught with disaster.