Oct price cap increase likely to push energy bill to over £10k... for a family of 4...

Vincero

MariaAH said:

I have some questions that those following this thread may be able to answer:
1. Which devices on standby are likely to use the most energy? 
2. Can you change setting, eg on TV, to reduce standby energy use?
3. Do fully charged devices (laptops. mobile phones) carry in using energy if still plugged in after they are fully charged?
4. Do empty chargers still plugged in (after laptop/phone disconnected) still use energy?
5. Is it worthwhile turning our oven off at the wall when not in use? (rangemaster with induction hob, fan oven, smaller multiuse oven, grill and LED clock)

Thanks

Side note: You can always get proper electricity meters installed on a separate circuit but keep in mind that most houses have a whole floor sharing a mains ring. And these would need to be properly fitted by a qualified electrician, but they only cost £30-40. Useful if say you wanted to properly monitor appliances on a separate circuit you can't use a plug-in monitor for such as shower, cooker, garage, car charger, etc.

In terms of questions:
1. Generally the older it is the worse it will likely be. Older cookers and microwave ovens with displays/timers are not great sometimes, same as with TVs.
TV DVRs (virgin TiVo, Freeview or sky recorders) ar essentially mini computers so will use more energy than say a normal set top box when on standby and definitely when recording.

Also, sometimes think about all the devices you actually have on standby but are ignored - e.g. many newer washing/drying machines are on standby but they don't have an indicator like say a TV.

2. Some devices / TV / DVRs have lower power standby options but it may reduce functionality - in some cases it may mean slower switching on times or not being able to perform some scheduled recordings, etc.
Computers for example have the option to suspend (suspend to RAM) which keeps it in a ultra low power state but still on with quick resume time, hibernate (suspend to disk) which saves the system state and turns off the machine* and has a slower resume, and of course power off* (which since Windows 8 is actually not much different from hibernate to improve boot time). It's worth remembering that * powering off a PC really still is in a standby state - ever since the ATX standard (mid-90s) there isn't generally a physical power switch on the front (there may be on the back) and it's just an electronic power on button. Unless you've got a really old or inefficient machine, that standby is unlikely to result in a noticeable power use.

3. Yes they do. Let's say a phone/tablet needs to use 50mA to stay in standby - if it's plugged in then it will sip that overall power from the mains charger.
Same with a laptop and most battery backed devices. Even if a laptop is off, that same electronic design as any other PC/computer with its electronically controlled on/off button (or waiting for a turn on signal from another device or timer) still sips some energy.

4. Yes they will but anything from the last 5 years for mobile chargers is likely to use almost nothing at all. Laptop chargers from the last 10 years or so will likely be similar and have what's known by some as a '0-Watt' mode when nothing is plugged in.

5. If you're not worried by the clock not being right, yeah sure - arguably it's a tiny bit safer that way as well in general.

TheGardener

Turning off the cooker - we tried this but the oven wouldn't actually work at all unless the clock was set so turning it off was a bit of a pain as we had to reset the clock everytime we wanted to use it  - and it is one of those infuriatingly confusing clocks to set

inkydolphin

I second the point about standby wattage of older electricals. Until recently I was using a Sky+ HD box that was using 21 watts when on, 14 watts in standby, and even 7 watts when shut down but still plugged in (but that mode was useless as it took the Sky box about 5 minutes to turn on from there). 

kuratowski

TheGardener said:

Turning off the cooker - we tried this but the oven wouldn't actually work at all unless the clock was set so turning it off was a bit of a pain as we had to reset the clock everytime we wanted to use it  - and it is one of those infuriatingly confusing clocks to set

My oven does this too, but I just set the clock to midnight every time - it doesn't need to be correct, I just need to tap the buttons to set it...

Magnitio

inkydolphin said:

I second the point about standby wattage of older electricals. Until recently I was using a Sky+ HD box that was using 21 watts when on, 14 watts in standby, and even 7 watts when shut down but still plugged in (but that mode was useless as it took the Sky box about 5 minutes to turn on from there). 

The later Sky Q boxes aren't much better - 16.5W standby and 19W in use. There is a similar shut-down mode which it goes into for about 3 hours each night, but that doesn't represent a particularly large saving. At 35p/kWh, that's about £50 per annum for 5 hours a day usage.

michaels

Vincero said:

MariaAH said:

I have some questions that those following this thread may be able to answer:
1. Which devices on standby are likely to use the most energy? 
2. Can you change setting, eg on TV, to reduce standby energy use?
3. Do fully charged devices (laptops. mobile phones) carry in using energy if still plugged in after they are fully charged?
4. Do empty chargers still plugged in (after laptop/phone disconnected) still use energy?
5. Is it worthwhile turning our oven off at the wall when not in use? (rangemaster with induction hob, fan oven, smaller multiuse oven, grill and LED clock)

Thanks

Side note: You can always get proper electricity meters installed on a separate circuit but keep in mind that most houses have a whole floor sharing a mains ring. And these would need to be properly fitted by a qualified electrician, but they only cost £30-40. Useful if say you wanted to properly monitor appliances on a separate circuit you can't use a plug-in monitor for such as shower, cooker, garage, car charger, etc.

In terms of questions:
1. Generally the older it is the worse it will likely be. Older cookers and microwave ovens with displays/timers are not great sometimes, same as with TVs.
TV DVRs (virgin TiVo, Freeview or sky recorders) ar essentially mini computers so will use more energy than say a normal set top box when on standby and definitely when recording.

Also, sometimes think about all the devices you actually have on standby but are ignored - e.g. many newer washing/drying machines are on standby but they don't have an indicator like say a TV.

2. Some devices / TV / DVRs have lower power standby options but it may reduce functionality - in some cases it may mean slower switching on times or not being able to perform some scheduled recordings, etc.
Computers for example have the option to suspend (suspend to RAM) which keeps it in a ultra low power state but still on with quick resume time, hibernate (suspend to disk) which saves the system state and turns off the machine* and has a slower resume, and of course power off* (which since Windows 8 is actually not much different from hibernate to improve boot time). It's worth remembering that * powering off a PC really still is in a standby state - ever since the ATX standard (mid-90s) there isn't generally a physical power switch on the front (there may be on the back) and it's just an electronic power on button. Unless you've got a really old or inefficient machine, that standby is unlikely to result in a noticeable power use.

3. Yes they do. Let's say a phone/tablet needs to use 50mA to stay in standby - if it's plugged in then it will sip that overall power from the mains charger.
Same with a laptop and most battery backed devices. Even if a laptop is off, that same electronic design as any other PC/computer with its electronically controlled on/off button (or waiting for a turn on signal from another device or timer) still sips some energy.

4. Yes they will but anything from the last 5 years for mobile chargers is likely to use almost nothing at all. Laptop chargers from the last 10 years or so will likely be similar and have what's known by some as a '0-Watt' mode when nothing is plugged in.

5. If you're not worried by the clock not being right, yeah sure - arguably it's a tiny bit safer that way as well in general.

You need to think about what is material.  Pretty much anything that runs off a battery (except for a car) will be negligible when charging or using, for example a phone on a charger will use pretty much zero to charge and as close to zero as makes no difference when charged whether plugged in or not.

The main tip is to do the touch test.  Waste electricity is heat so if a set top box, charger brick etc is moderately warm then it is consuming power, otherwise don't worry about it.

Vincero

michaels said:

You need to think about what is material.  Pretty much anything that runs off a battery (except for a car) will be negligible when charging or using, for example a phone on a charger will use pretty much zero to charge and as close to zero as makes no difference when charged whether plugged in or not.

The main tip is to do the touch test.  Waste electricity is heat so if a set top box, charger brick etc is moderately warm then it is consuming power, otherwise don't worry about it.

Agreed, but I tried to be as factual as possible. It would be wrong to say there is absolutely no vampire power from some charger devices when there is nothing attached.

In terms of a phone left on a charger, assuming it uses say 15 mAh to keep itself in standby with cell and WiFi connections live and it was left connected and unused like that for a year, would use at least 486 Wh in a year. It would likely be a bit higher (which is why I assumed 50mAh in example) for a phone someone actually uses properly with background apps, etc.

An absolutely inconsequential to most people, but not zero.
What people would find more shocking is that for the average smartphone user they probably use around 100 kWh a year charging their phone....

Edit: made a mistake - roughly 4kWh over a year...

xeny

An absolutely inconsequential to most people, but not zero.
What people would find more shocking is that for the average smartphone user they probably use around 100 kWh a year charging their phone....

273 Wh/day ? That seems a bit excessive.

k_man

Vincero said:

michaels said:

You need to think about what is material.  Pretty much anything that runs off a battery (except for a car) will be negligible when charging or using, for example a phone on a charger will use pretty much zero to charge and as close to zero as makes no difference when charged whether plugged in or not.

The main tip is to do the touch test.  Waste electricity is heat so if a set top box, charger brick etc is moderately warm then it is consuming power, otherwise don't worry about it.

Agreed, but I tried to be as factual as possible. It would be wrong to say there is absolutely no vampire power from some charger devices when there is nothing attached.

In terms of a phone left on a charger, assuming it uses say 15 mAh to keep itself in standby with cell and WiFi connections live and it was left connected and unused like that for a year, would use at least 486 Wh in a year. It would likely be a bit higher (which is why I assumed 50mAh in example) for a phone someone actually uses properly with background apps, etc.

An absolutely inconsequential to most people, but not zero.
What people would find more shocking is that for the average smartphone user they probably use around 100 kWh a year charging their phone....

Can you confirm you use of mAh? Over what period?

Regarding standby power while plugged in, wouldn't the standby power get used whether the phone is left on the charger or not, but just be running down the battery in the latter. The battery then needs to be charged.
Unless you are comparing phone left plugged in Vs phone unplugged and turned off?

And, as above, can you check your maths on the 100 kWh per year?
Most mobiles have batteries of around 4000mAh.
At a nominal 5V (to make the maths easier) is 20Wh.
Note this matches the typical 1 - 2 hour charges at 10 - 20W (2 to 4A at 5V).

Assuming charged once per day gives approx 7 kWh per year.

To get to 100 kWh, it would need to be charging at full rate almost 24/7.

k_man

@Vincero

Were you possibly missing out the 3.7v for the 50mA that a mobile uses in standby.

Which is only 0.2W. or 4Wh per day.

Back to the OP.
Mobile chargers don't use much, even when charging, and virtually nothing when devices are fully charged.
Your Tapo will confirm this.

So if they are regularly used turning off has little benefit.
But if rarely used then turning off/unplugging may be worth it.