DAB radios in the UK

[Fanie]

Here is the proof

[charliecoutas]

Good comments. Bob: the set top box is on 24 hrs every day. It does use 22 watts which equates to £41.24 per year. This is what I listen to during the night. The new little Roberts Radio, which I love, is powered by a USB charger which I just measured at 0.83W on and 0.4W in standby.

The main TV (Samsung) uses 14 watts in standby, so this must be addressed first.

Energy prices in the UK are causing quite a lot of hardship.

Charlie

[Stephen Moss]

Stephen, CPR

Thanks for your input. I looked at the reviews of these radios and the worst ones were terrible.

I have a Azatom DAB clock radio (not the one I linked to) for a few years now and it has been fine, although I suspect the USB out for charging my phone may have died, but I don't use it with my new phone as it came with a fast charger.

The reason for this is as follows: I noticed that my smart meter said I was using 6.8 pence per hour, last thing at night when all the lights and most other things were off. What remained was all the stuff on standby - 2xTV, 2xFridge plus a whole load of plug-in wall psu's 5/12V. Now 6.8p/hour equates to £595.68 per year, which seems excessive.

That does seem rather excessive, as it is close to my annual bill, have you not miscalculated there?
Surely it is not 6.8p per hour as in time, which is how you appear to have calculated the total cost ((6.8p * 24h * 356d) / 100), but per Kilowatt hour, so it should take  several nights to consume 1KW of energy. Otherwise, if that was the cost just for your overnight standby power usage then I would think your full annual bill must be in excess of 5K.

[charliecoutas]

Thanks Stephen. If I press the right buttons on the smart meter, it says current load = 0.3KW. The little remote monitor also shows either 300W or 6.8p/hr. A pal lent me a Power Meter which I can plug individual items into, the attached shows some results so far (a bit messy at the end, EXCEL is not my thing).

Yes, my calculation was watts*24*365/100=Pounds to pay. Normal electricity bill £1200(ish), Gas £1100(ish)

By selectively switching off breakers on my consumer unit I found that Ring Main no1 contains the culprit, still looking into it.....

Charlie

[ken_k]

oops posted on wrong page please delete




 

[charliecoutas]

I think you are right Stephen, I'll have another look at my calculations. But the annual bill of £1200 is right.
Just driven back from the museum.

Charlie

[See_Mos]

I wondered about sticking a timer switch on the entertainment stack to cut everything off overnight.

There is a Humax Freesat box, Toshiba DVD player, Toshiba TV, a Marantz network receiver and Marantz CD player.

[RGV250]

Hi Charlie,
I think you are worried about the small appliances more than the big hitters. We had a directive at work to turn off conveyors etc but nothing about the 11kw fans. I tried to point out the logic but the big bosses had obviously been told by some university student what to do.
I would question your TV on standby, I have a 50" Hitachi in the kitchen and that is drawing less than 1W on standby so maybe that is wrong?, also only 42W when on. I also have a Samsung TV so will check that later when not watching. Also you calculated when on it costs £122/year but unless it is on 24/7 that is not accurate cost.

Bob

[John Lawton]

Charlie,

your PDF is interesting, but there seem to be a few omissions, namely household 'white goods' such as fridge, freezer, cooker, washing machine, dishwasher and also kettle and clothes iron, electric shower (if fitted). Some of these are high power but low duty cycle. I plugged our washing machine into a power plug for a week to measure it's cumulative (kWh) power consumption and although I can't remember the figures, I concluded that it was well worth running the machine on the overnight low tariff, the same applies to the dishwasher that is run most nights. All these items will add to your bill

John

[RGV250]

Hi,

I concluded that it was well worth running the machine on the overnight low tariff, the same applies to the dishwasher that is run most nights

I do that but I recently had a fire safety survey and he was dead against it.

Bob

[John Lawton]

So is it safe during the day but unsafe overnight?



John

[RGV250]

So is it safe during the day but unsafe overnight?

You are not asleep during the day so more likely to get out. I still do it though.

Another thought on turning devices off repeatedly that are designed to be on standby. Are you likely to cause premature failure?

Bob

[John Lawton]

Another thought on turning devices off repeatedly that are designed to be on standby. Are you likely to cause premature failure?

That's an interesting point. I recently revisited a client's house where there were some LED lighting systems installed over 10 years ago that I had designed. We removed a couple of them as the client is downsizing.

I ran the units on the bench with their original 24V 250W psu's that had been running on standby for all that time. One of them failed within a day after having being switched on and off a number of times. That shows how the switch-on surge can be very stressful for equipment. We are reinstalling the lights with new power supplies...

John

[charliecoutas]

I didn't include kettles cookers showers and dishwashers etc because it's the power used when not in use the bothers me and all these are either on or off. The  two fridge/freezers are buggers to get at their mains supplies but I may have to. The Samsung TV and everything else was measured using a Kikusui power meter which we know has been calibrated, so those are correct. I saw some directive/European Union thingy that said standby power had to be 1W  or less. Ha!

My calculations were done as follows: 1kw/hr cost me 21.4p. So if I burn 1000 watts for 1 hour I get charged 21.4p. (Plus standing charge and VAT but ignore that for now).

This means that burning 1 watt for 1 year will be 1x24x365 watt/hours=8760 Divide this by 1000 and get kw/hr
8760/1000=8.76kw/hr. Multiply this by the cost of 1kw/hr 8.76x21.4=£1.87   So burning 1 watt for a whole year will cost £1.87. Therefore the cost of my Samsung TV on standby for the year is 13.3Wx1.87=£24.87

I slipped up somewhere because this is not quite the same as I had before, but I think it's near enough.

Could somebody in the know explain if we pay a penalty for a low power factor? Many of my items have a poor PF and I wonder how this will affect the price?

I agree about the dangers of overnight high power devices. We won't do that nor will we leave the clothes dryer on when we go out. Do you pay a bit more for daytime power on these overnight deals?

Charlie

[RGV250]

Do you pay a bit more for daytime power on these overnight deals

Yes, I think the break even point is around 30% but have not got the figures to hand. That might be different when I finally have to have the anxiety meter.

I do find it laughable the reason I have to change is the equipment is old.

The Radio Teleswitch Service (RTS), which allows older Economy 7 meters to switch automatically between peak and off-peak rates, is being switched off because the technology is obsolete, no longer maintainable, and reaching the end of its operational life.

I am sure somebody on the forum could probable design a new one for peanuts but that doesn't suit their agenda.

As for the power factor, I do not think it is like industry where you get fined otherwise there would be companies selling household power factor correction equipment. Does the meter show if it is leading or lagging.

BTW, my Samsung TV does not even show on the meter on standby, 50W when on.

Bob

[John Lawton]

My digital dual rate meter has a voltage input line that switches the rate.
This is fed from an old rotary dial timeswitch which has various tabs to set the on/off times.

Not very digital at all and it works fine

Octopus still keep suggesting a 'smart' meter but I ignore them.

John

[charliecoutas]

Bob, "Does the meter show if it is leading or lagging."  Probably but I don't know how to do it. It measures phase angle, reactive power and can even tell you what Fanie had for supper but I don't know how. I suspect the PF's are all leading due to the widespread use of switched mode psu's. They usually rectify the mains up to around 340V DC and bung it in a capacitor before switching operations. It's the leading-edge charging of that capacitor that causes the leading power factor. Over the whole country that must represent a large loss of actual power?

John: The name Venner Time Switch came to mind. Can you, er, adjust the timings yourself?

Charlie

[John Lawton]

SMPS are supposed to have power factor correction circuitry in order to pass EMC regs on mains harmonics for some time now so it's odd if they don't.

John: The name Venner Time Switch came to mind. Can you, er, adjust the timings yourself?

Yes, like that. I could do if I cut the security tag off, but would I?



John

[charliecoutas]

Power factor correction only applies above a certain power level, and I think it's above 1.5Kw but I'm not sure.

I visited a friend many years ago and on the kitchen wall was an electricity meter with a short length of 2.5mm insulated (brown) copper wire jammed between the AC live in and the AC live out.

"What's that for?" I asked?
It reduces the bill considerably" was his answer!

Charlie

[John Lawton]

No it's much worse than that. For lighting power supplies I believe the power output threshold is 25W, otherwise it's 75W, so it catches a lot of equipment.

I say 'believe' because getting correct information on the current standards is a nightmare in itself.

John