Intelligent Octopus Go/Eon next drive + a dehumidifier ifier

waqasahmed

So the idea would be to get a heat pump eventually and that would obviously be the cheapest solution (in terms of running costs)

Has anyone ran a dehumidifier during the cheaper hours and then put gas heating on after, to find that their heating costs were a bit cheaper? I can see that it'd probably be more expensive if you didn't have such an energy plan, but with an energy plan where electricity is cheap overnight I'm not so sure.

Has anyone done this and noticed that their heating costs were cheaper? 

Petriix

I run a dehumidifier overnight on the cheap rate. It uses (and therefore outputs as heat) 320W so roughly 2kWh over the 6 hour cheap window on Intelligent Octopus Go.

It's impossible to measure whether the heating costs are lower because there are too many other variables but 1kWh of cheap electricity costs 7p and 1kWh of gas heating at 90% efficiency is pretty much the same so it's pretty much moot.

The real benefit of running the dehumidifier is the ability to keep windows closed, retaining heat indoors rather than venting it with the damp air. Probably quite a big saving there. And of course the absence of mould. 

waqasahmed

Petriix said:

I run a dehumidifier overnight on the cheap rate. It uses (and therefore outputs as heat) 320W so roughly 2kWh over the 6 hour cheap window on Intelligent Octopus Go.

It's impossible to measure whether the heating costs are lower because there are too many other variables but 1kWh of cheap electricity costs 7p and 1kWh of gas heating at 90% efficiency is pretty much the same so it's pretty much moot.

The real benefit of running the dehumidifier is the ability to keep windows closed, retaining heat indoors rather than venting it with the damp air. Probably quite a big saving there. And of course the absence of mould. 

The not venting it with damp air is more what I was getting at ie: I figured a less humid environment would make gas heating a bit cheaper too 

FlorayG

I have a whole house forced air ventilation system to keep the house dry and it DEFINITELY keeps the house warmer and makes heating costs less. I guess a humidifier would work but would you not need one in each room?

Newbie_John

One of the less known facts for dehumidifier is that they release more energy than they take from the grid - for simplicity let's say 1kWh taken from the grid results in 1.5kWh output in heat (heat from heating air + latent heat).

So there's a lot of little bits that can add up - also what @Petriix said, you don't have to open windows to dry the air (saving heat), some people say that dry air feels warmer etc.

Still more expensive than gas (unless cheap night tariff) and much much worse in efficiency than heat pump.

tlcgrantham

waqasahmed said:

So the idea would be to get a heat pump eventually and that would obviously be the cheapest solution (in terms of running costs)

Has anyone ran a dehumidifier during the cheaper hours and then put gas heating on after, to find that their heating costs were a bit cheaper? I can see that it'd probably be more expensive if you didn't have such an energy plan, but with an energy plan where electricity is cheap overnight I'm not so sure.

Has anyone done this and noticed that their heating costs were cheaper? 

I’ve started to run 2 dehumidifiers during a 5pkwh period during the night and have noticed a 20% reduction in gas heating use during the morning and the house heats up much quicker. 

waqasahmed

FlorayG said:

I have a whole house forced air ventilation system to keep the house dry and it DEFINITELY keeps the house warmer and makes heating costs less. I guess a humidifier would work but would you not need one in each room?

Perhaps but you can pick them up for between £0 and £20 On Facebook marketplace 

waqasahmed

tlcgrantham said:

waqasahmed said:

So the idea would be to get a heat pump eventually and that would obviously be the cheapest solution (in terms of running costs)

Has anyone ran a dehumidifier during the cheaper hours and then put gas heating on after, to find that their heating costs were a bit cheaper? I can see that it'd probably be more expensive if you didn't have such an energy plan, but with an energy plan where electricity is cheap overnight I'm not so sure.

Has anyone done this and noticed that their heating costs were cheaper? 

I’ve started to run 2 dehumidifiers during a 5pkwh period during the night and have noticed a 20% reduction in gas heating use during the morning and the house heats up much quicker. 

20% is a substantial saving. Assuming that's say 2000 kWh that's a saving of £110 ish of gas at 5.44p/kWh 

Reed_Richards

My dehumidifier uses about 225 W and I run it for the 7 hours of my cheap EV tariff electricity.  The total was 1.576 kW last night, according to my Tapo P110 which I use to schedule the on and off times.  This must be contributing a little to heating my house but as it is the open-plan living room+dining room+corridor I have never noticed a difference.  If I put it in a bedroom and close the door then I do notice that the room gets a bit warmer.  

waqasahmed

Newbie_John said:

One of the less known facts for dehumidifier is that they release more energy than they take from the grid - for simplicity let's say 1kWh taken from the grid results in 1.5kWh output in heat (heat from heating air + latent heat).

So there's a lot of little bits that can add up - also what @Petriix said, you don't have to open windows to dry the air (saving heat), some people say that dry air feels warmer etc.

Still more expensive than gas (unless cheap night tariff) and much much worse in efficiency than heat pump.

Do you have the more complex understanding of that?
I think that's quite interesting if so

QrizB

waqasahmed said:

Newbie_John said:

One of the less known facts for dehumidifier is that they release more energy than they take from the grid - for simplicity let's say 1kWh taken from the grid results in 1.5kWh output in heat (heat from heating air + latent heat).

Do you have the more complex understanding of that?
I think that's quite interesting if so

See for example:

https://forums.moneysavingexpert.com/discussion/comment/79505418/#Comment_79505418

or

https://forums.moneysavingexpert.com/discussion/6392759/using-a-dehumidifier-as-a-heater-efficiency-of-dessicant-vs-compressor

I think you'd struggle to return a COP of more than about 1.5, but (as Tesco say) every little helps!