Which devices are boosting your electricity bill?

[daiking]

47 minutes ago, DamonHD said:

 

Mainly making sure that things are really off when we are not using them (eg the microwave, which otherwise used 5W for the clock we never set, over time possibly more than the energy we used cooking in it).

 

And very carefully checking the specs for replacement appliances as we bought them.  The range of consumptions for devices doing nominally the same thing is remarkable, and shops have been poor about pointing out anything other than the shiny shiny.  Trip up on that and you are wasting energy for the device's entire life.

 

That one smart plug for the the TV, DVD, Xbox makes a difference I think, which would otherwise push up our overnight use by ~50%.

 

I also cut down power for my servers sufficiently (from ~640W to ~2W) that the whole lot runs off-grid on a separate system.  The first bit (replacing a rack of servers with a Raspberry Pi) is the important part.  The off-grid system is more-or-less showing off having done that.

 

Nothing very clever.

 

Rgds

 

Damon

 

That’s quite extreme and I don’t think you are any more typical (well maybe ?) than AliG with his swimming pool.

 

IIRC you live (by choice) in a small house - that’s a great way of limiting consumption. Unfortunately in anything bigger it just runs away from you. And it must be an allegory for many things. I bet you don’t have a fridge freezer, wine cooler and refrigerated drinks machine (?) . Nor 3 small streaming speakers (5W on standby). Low consumption is a philosophy about more than just low energy appliances. And something, as AliG finds, you need obedient/faithful followers in a family situation. We increased a 75m2 house up to about 130m2 and filled it with more shit nobody needs. And when the riveting subject of energy costs comes up, I *think* we’re relatively reasonable here but it would drive me (even more) insane time seriously attempt to change behaviours or maintain a serious low consumption regime.

 

Where do you stand on cordless devices? Losses via batteries and devices permanently on charge and empty chargers permanently plugged in even when devices are in use. Plenty of boys and their 20 toys for LXT batteries here.

[AliG]

OK, I have put various devices into a spreadsheet depending on either tested consumption or the EU energy label.

 

There are more to add such as ovens and microwave.

 

I still think the most surprising one is that a Sky Q box uses more electricity than a fridge/freezer.

 

I already have accounted for around 11kWh here, I would expect the dehumidifier to be another couple and the various heating pumps to be quite a bit.

Device Consumption.xlsx

Edited August 9, 2020 by AliG

[Ferdinand]

A swimming pool and a games room AND a 70 sqm kitchen?

 

You old lounge lizard you.

 

(Personally I'm planning a dance floor - but not enough depth for the sprung maple version without digging up all the concrete and the ufh).

Edited August 9, 2020 by Ferdinand

[daiking]

2 minutes ago, AliG said:

OK, I have put various devices into a spreadsheet depending on either tested consumption or the EU energy label.

 

There are more to add such as ovens and microwave.

 

I still think the most surprising one is that a Sky Q box uses more electricity than a fridge/freezer.

 

I already have accounted for around 11kWh here, I would expect the dehumidifier to be another couple and the various heating pumps to be quite a bit.

Device Consumption.xlsx 11.62 kB · 0 downloads

Have you nothing better to do on a Sunday morning? ? Its lovely in Manchester, is it not in Scotland?

 

I have cleared a drain thats been blocked with a lump of concretey crap for 2 years (grim) and jet washed a path and now I smell like a blocked drain ?

So, this spreadsheet ....

 

[AliG]

I am watching the F1. So plenty of time to do other things.

[daiking]

10 minutes ago, AliG said:

I am watching the F1. So plenty of time to do other things.

Unless the leaders get punctures again, the spreadsheet is probably more interesting. At least I can’t watch it.

[joe90]

2 hours ago, AliG said:

I am watching the F1. So plenty of time to do other things.

I am watching the highlights on channel 4 later, so turned the radio off so I don’t hear which Mercedes won!

[Temp]

Don't you just hate it when you turn the TV on and someone has left it on the news channel and the first words you hear are "Hamilton/Botas has won the xyz GP......".   Why can't that start with "and in motoring news..."? At least that would give me time to turn my ears off.  

[AliG]

OK, I found one thing.

 

The pool has two big LED lights that create a really nice effect.

 

They work off a wireless remote control, but the transformer is just plugged into a normal socket in the plant room.

 

The transformer uses 20W when the lights aren't on. 51W when they are on.

 

So that's around 175kWh a year.

 

I will switch it off and people can flick the switch before they use the pool. It has had an unexpectedly high amount of use this year with lockdown.

 

My wife likes to compare the house to a cruise ship where you can always sit somewhere else and find something else to do. In this analogy, I may be the cruise ship maintenance people!

 

My daughter says the cost of the projector for her endless watching of The Simpsons is totally worth it, but she might try not to turn on all the kitchen lights every time.

Edited August 9, 2020 by AliG

[Ferdinand]

9 minutes ago, AliG said:

OK, I found one thing.

 

The pool has two big LED lights that create a really nice effect.

 

They work off a wireless remote control, but the transformer is just plugged into a normal socket in the plant room.

 

The transformer uses 20W when the lights aren't on. 51W when they are on.

 

So that's around 175kWh a year.

 

I will switch it off and people can flick the switch before they use the pool. It has had an unexpectedly high amount of use this year with lockdown.

 

My wife likes to compare the house to a cruise ship where you can always sit somewhere else and find something else to do. In this analogy, I may be the cruise ship maintenance people!

 

My daughter says the cost of the projector for her endless watching of The Simpsons is totally worth it, but she might try not to turn on all the kitchen lights every time.

 

You need to borrow the head of somebody's secret police...

Edited August 9, 2020 by Ferdinand

[AliG]

Right, I found the original specification for the pool dehumidifier.

 

It states 2850 kWh per year assuming 1 hour of use a day. I suspect I am maybe nearer to 2500.

 

Actually their estimate of the energy consumption for the pool was pretty accurate.

 

 

[AliG]

I reckon I can get consumption down around 4-500kWh a year with this information. £5-60 a year. Not a massive saving, but I suspect everyone could get their consumption down by around 5% if they did this kind of audit.

 

I did invest £9 into a Wi-Fi smart plug that measured consumption.

 

I had already done quite a few things to reduce consumption -

 

Setting lights to switch off automatically.

SettingTVs to switch off after a period of zero use.

Retiming the heating so that it is more likely to be running everywhere at the same time so the boiler and pumps are not firing up for just one room, this reduced gas consumption also.

Switching off devices that are never used and have a few watts of standby consumption.

 

What is interesting is that as fast as things are getting more efficient, the proliferation of smart devices that are always on is eating into some of the consumption saving. Also TVs have a lower consumption per inch, but this has been pretty much offset by the TVs becoming massively larger.

 

A funny example of this is a feature that Tesla recently introduced. A great feature of electric cars is that you can turn he heater on to warm them up before you get in. They have introduced a feature where you can set the car to be warm at the same time every week day or 7 days a week. Of course once you turn this feature on the heater runs every day whether or not you are going anywhere. Probably uses 1kWh every time it runs, the heater uses 6kW. So this might be using a few hundred kWh a year. They have finally moved to an ASHP in the Model Y to reduce this waste. Still a warm car in the morning is worth it.

 

The one I am most pleased with is that the LED strip in the cinema room was running at 80W. I reduced the dimmer to just less than 50W consumption with no visible reduction in the light output. It is the second most used light in the house. I did try on the kitchen lights but they started to dim almost immediately.

 

 

Edited August 9, 2020 by AliG

[pdf27]

50 minutes ago, AliG said:

Right, I found the original specification for the pool dehumidifier.

It states 2850 kWh per year assuming 1 hour of use a day. I suspect I am maybe nearer to 2500.

Actually their estimate of the energy consumption for the pool was pretty accurate.

That's astonishingly high. Any chance you could address the problem differently, for instance by fitting an appropriately sized MVHR system running off a humidistat?

[SteamyTea]

17 MWh a year does not sound too bad.

I use between 3.8 and 5 MWh a year depending on how cold the winter is.

And there is only me, in a small house.

So if there is 4 of you, and your house probably has 4 times the area, or more, than mine, and you have a pool, just pay the bill.

200 W of LED lighting seems excessive mind. My whole house only has 30 W.

[AliG]

That’s just the cost of running a swimming pool.

 

There is 40,000 litres of water in the pool, so it is dealing with constant evaporation from that. The room is kept at a constant relative humidity level of 60 and I have never seen even the slightest hint of condensation in the room. To be exact the metal lock on the patio doors does see water condense on it. Indeed it all looks as good as new after three years.
 

For the last 18 days we have been running 39kWh per day of usage.  Usage by the car will have been a lot less than normal, offset by more use from being at home.

 

We have generated around 16kWh a day over the same period.

 

I have had a stab at food cooking usage and I reckon that runs to around 1.5kWh per day so over 500 a year. All of us seem to eat different items for most meals otherwise you could cut this down a bit.

 

The various heating pumps use around 40W when they are running. They actually display instantaneous usage on the pumps. In the summer probably three of these pumps run 3 hours a day for hot water and pool heating so that would be 360w say 65kWh for 6 months of the year and 9 pumps running 5 hours a day in the winter so. So 320kWh in the winter or around 400kWh a year. This is probably the vast majority of higher electricity usage in the winter for us plus a bit more use of lights.

 

 

 

 

[AliG]

2 minutes ago, SteamyTea said:

17 MWh a year does not sound too bad.

I use between 3.8 and 5 MWh a year depending on how cold the winter is.

And there is only me, in a small house.

So if there is 4 of you, and your house probably has 4 times the area, or more, than mine, and you have a pool, just pay the bill.

200 W of LED lighting seems excessive mind. My whole house only has 30 W.

It’s excessive relative to the average person but not relative to the size of the house. It is quite unusual in that the electricity bill is higher than our gas bill. 
 

It is more me just enjoying the process of optimising things and seeing if there are any obvious areas of waste. I am sure if my wife ran things it would be over 20000kWh a year and the gas bill would also be a third higher.

[SteamyTea]

4 minutes ago, AliG said:

It is more me just enjoying the process of optimising things and seeing if there are any obvious areas of waste.

Go to eBay, find and old CurrentCost energy meter, get a RPi and a TTL lead and get some real decent data. Seeing what happens every 6 seconds can be quite interesting.

It picked up my faulty fridge within 2 days of it going wrong.

 

Also my old PC was using 250 W, then the newer laptop used 30 W, current one 8 W.

Edited August 9, 2020 by SteamyTea

[AliG]

We used to have something like that in our old place that we were sent by the electricity company.

 

I assumed that we would have a smart meter here, but there still are not 3 phase smart meters available.

 

Just checked the consumption of the boiler which brings the total on my spreadsheet to around 14.5kWh a year which seems about right before adding in the consumption the Tesla.

[Nickfromwales]

More PV???

[Reiver]

We used to have s

4 minutes ago, AliG said:

We used to have something like that in our old place that we were sent by the electricity company.

I assumed that we would have a smart meter here, but there still are not 3 phase smart meters available.

Such things do exist - would it be worth checking around different energy companies to see if a different one could provide it?

[SteamyTea]

The old CT clamp CurrentCost does 3 phase.

It is at @joe90s at the moment.

Though it should not be hard to make up something that just reads the normal meter LED flashing.

[pdf27]

26 minutes ago, AliG said:

That’s just the cost of running a swimming pool.

 

There is 40,000 litres of water in the pool, so it is dealing with constant evaporation from that. The room is kept at a constant relative humidity level of 60 and I have never seen even the slightest hint of condensation in the room. To be exact the metal lock on the patio doors does see water condense on it. Indeed it all looks as good as new after three years.

Big swimming pools use heat exchange ventilation to control humidity (https://www.dantherm.com/gb/technologies/swimming-pool-dehumidification/how-to-choose-the-right-dehumidifier-for-indoor-pools/), with dehumidifiers used for small ones due to the lower capital cost.

 

Max water carrying capacity of air is 0.025 kg/kg at 28°C (https://www.engineeringtoolbox.com/humidity-ratio-air-d_686.html), so 0.015 kg/kg at 60% humidity is about right in the exhaust air. 

40m³ pool suggests a surface area of about 30m² and an air volume of about 150m³. That suggests the most the air could absorb before it's saturated is a couple of litres (150m³ of air weighs ~180kg, at 28°C it takes 0.01kg of water per kg of air to saturate it -> 1.8kg of water). I'm guessing your run the dehumidifier multiple times per day for short periods?

Best I can find is energy efficiency values of 0.5 kWh/l, so you're looking at 16 litres of water to remove from the air per day (less if it's less efficient).

Assuming the outside air is 20°C and 60% humidity, every m³ of air ventilation would remove ~0.1 l of water, so you would need ventilation at ~160 m³/day which is pretty minimal. Pretty much any MVHR unit would do that, although you'd need an external humidistat to prevent the humidity going too low. There might be a couple of days per year when it isn't enough (very hot and humid outside), but there would be no need to remove the existing dehumidifier, just turn it off normally.

 

Looks like payback time for a cheap MVHR unit (DIY installed) would be 12-18 months to me...

[AliG]

I put as much PV on as I could whilst keeping the roof looking nice, I wouldn't start messing around with it now.

 

I wasn't just thinking about my consumption, I thought it would be interesting for everyone to think which devices are the biggest energy hogs in the house.I have updated the spreadsheet and included the car which has averaged 492w/Mile since purchase. we would normally do 7000 miles a year. 

 

Device Consumption.xlsx

[Ferdinand]

Can you do anything about that Tumble Dryer?

 

eg Pulley Maid.

[AliG]

24 minutes ago, pdf27 said:

Big swimming pools use heat exchange ventilation to control humidity (https://www.dantherm.com/gb/technologies/swimming-pool-dehumidification/how-to-choose-the-right-dehumidifier-for-indoor-pools/), with dehumidifiers used for small ones due to the lower capital cost.

 

Max water carrying capacity of air is 0.025 kg/kg at 28°C (https://www.engineeringtoolbox.com/humidity-ratio-air-d_686.html), so 0.015 kg/kg at 60% humidity is about right in the exhaust air. 

40m³ pool suggests a surface area of about 30m² and an air volume of about 150m³. That suggests the most the air could absorb before it's saturated is a couple of litres (150m³ of air weighs ~180kg, at 28°C it takes 0.01kg of water per kg of air to saturate it -> 1.8kg of water). I'm guessing your run the dehumidifier multiple times per day for short periods?

Best I can find is energy efficiency values of 0.5 kWh/l, so you're looking at 16 litres of water to remove from the air per day (less if it's less efficient).

Assuming the outside air is 20°C and 60% humidity, every m³ of air ventilation would remove ~0.1 l of water, so you would need ventilation at ~160 m³/day which is pretty minimal. Pretty much any MVHR unit would do that, although you'd need an external humidistat to prevent the humidity going too low. There might be a couple of days per year when it isn't enough (very hot and humid outside), but there would be no need to remove the existing dehumidifier, just turn it off normally.

 

Looks like payback time for a cheap MVHR unit (DIY installed) would be 12-18 months to me...

 

Thanks for that very detailed response. I am just calling it a dehumidifier, but it is a massive box that also heats the pool using a heat exchanger connected to the boiler and supplies fresh air to vents in front of all the windows in the room to prevent condensation and improve air quality.

 

The spec has been set up to remove an average of 2l/hr from the air and for a room of 338m3 versus the roughly 220m3 of volume that we actually have. So it may be that it is using somewhat less electricity than in the spec or it is over ventilating the room. The spec is based on an average of 0.5 changes per hour.

 

It does indeed run for a short amount of time many times a day, but it also is tasked with quickly raising the air temperature in the room form 22C to the high 20s when you open the pool and start to use it.

 

As I assume it runs off the humidistat, if the spec over ventilates the room, I would assume it uses less electricity in practice than the spec suggests.

 

 

 

Edited August 9, 2020 by AliG