Extra Uses For Off-Peak Electricity

[ME_UK]

My post was at a 'consider' stage but I subsequently decided against this prior to reading your reply.

I've also looked at a freestanding infrared heater panel because my wife is often at home for several hours during the day, mainly in the open plan kitchen-dining-conservatory area. Maybe I will try one as the cost is relatively low & it would be powered from overnight battery storage plus any winter solar generation on cold sunnier days.

​

We're only 11 days in but here's the cost for keeping our conservatory (glass roof) at 19 degrees for the last week - that's an average of 51p that we're more than happy with.....

I realise this isn't portable or meets your brief - but for anyone else interested in one!

Date	KW	Cost
17/09/2022​	8.5​	£ 0.61
18/09/2022​	10.9​	£ 0.78
19/09/2022​	8.6​	£ 0.61
20/09/2022​	0.1​	£ 0.01
21/09/2022​	11.4​	£ 0.81
22/09/2022​	1​	£ 0.07
23/09/2022​	9.8​	£ 0.70
24/09/2022​	10​	£ 0.71
25/09/2022​	0​	£ -
26/09/2022​	11.6​	£ 0.83​

 

[thewishy]

My post was at a 'consider' stage but I subsequently decided against this prior to reading your reply.

I've also looked at a freestanding infrared heater panel because my wife is often at home for several hours during the day, mainly in the open plan kitchen-dining-conservatory area. Maybe I will try one as the cost is relatively low & it would be powered from overnight battery storage plus any winter solar generation on cold sunnier days.

​

Cool, I hear good things about IR for rooms which aren't frequented for extended periods. A2A ASHP also goes a good job of heating the air, so it feels warm quickly (well before the fabric of the room heats up)

 

[NewbieT]

I'd like to consider one or two night storage heaters to charge up overnight (Intelligent Octopus, winter months) for the part of the house most commonly used in the day.

Can anyone recommend a product to achieve the following:

• Charge overnight to set schedule, discharge programmable preferably via an app or wifi
• Discharge easily adjustable to accommodate different daily requirements but can also accommodate simple on-off
• Moveable
• Can be plugged in, not hard wired

& To give me some idea....From an ambient ~6ºC in a 12m² space, what energy rating would be required (2kW, 2.5kW etc) to give at least 6 hours heat at 19-20ºC?

If you can compromise on ‘portable’. Have a look at Dimplex Quantum. The bricks inside are very heavy but that’s how they store the energy. Might need a timer & contactor on the supply. With 1 and 2 kW input sizes you could run off a 3 pin plug.

Edit: officially the manual says fused spur, so speak to a friendly electrician!

 

[Jason71]

If you can compromise on ‘portable’. Have a look at Dimplex Quantum. The bricks inside are very heavy but that’s how they store the energy. Might need a timer & contactor on the supply. With 1 and 2 kW input sizes you could run off a 3 pin plug.

I was under the impression there was no such thing as a portable storage heater? I thought they had to be mounted for safety reasons

 

[Drew57]

Yes, when I looked into it, storage heaters do need a fused spur and also wall mounting.

The Quantum range looks good but I won't be pursuing that.

 

[SteveJol]

My hot water tank is currently heated by the gas boiler once a day. It also has an electric immersion heater as backup.

This thread has me thinking whether installing a timer and switching to heating via the immersion, off peak, might be worth it?

Anyone else doing this already?

 

[robmcm]

My hot water tank is currently heated by the gas boiler once a day. It also has an electric immersion heater as backup.

This thread has me thinking whether installing a timer and switching to heating via the immersion, off peak, might be worth it?

Anyone else doing this already?

Looking into it, someone recommended this https://www.amazon.co.uk/gp/aw/d/B00BJIB97K/ref=cm_cr_othr_mb_bdcrb_top?ie=UTF8#

Will work well with Go Faster ending at 6:30, shame IO finishes at 5:30

 

[Mrklaw]

Looking into it, someone recommended this https://www.amazon.co.uk/gp/aw/d/B00BJIB97K/ref=cm_cr_othr_mb_bdcrb_top?ie=UTF8#

Will work well with Go Faster ending at 6:30, shame IO finishes at 5:30

immersion should hold hot water fine after 5:30 definitely worth it.

My experiment with the ufh not so much. Put it on for an hour set to 24c so it should be on full bore, ending at 5:30 end of IO period - got up at 6:45 and the ensuite was barely noticable and the main bathroom not at all.

Will try two hours tonight but much more than that and I might as well just have it on for when we get up at peak (but shorter time)

 

[Bacon]

My hot water tank is currently heated by the gas boiler once a day. It also has an electric immersion heater as backup.

This thread has me thinking whether installing a timer and switching to heating via the immersion, off peak, might be worth it?

Anyone else doing this already?

I have been doing a few weeks.

With the boiler using gas for 30 minutes to heating the hot water, it used 8.5kwh.

The immersion heater which runs on and off for 3 hours overnight used 3kwh of electricity.

 

[scdoubleu]

Be careful which time switch you use for an immersion heater. Most of the generic timers are not really rated for a 3 kW load for hours at a time. I would recommend this one as it's specifically designed for the purpose. Ours has been doing a sterling job since the start of the year.

You may also need an additional heavy-duty/heat-resistant cable between the timer and immersion heater. This one is recommended.

Don't skimp on these things.

 

[ME_UK]

Be careful which time switch you use for an immersion heater. Most of the generic timers are not really rated for a 3 kW load for hours at a time. I would recommend this one as it's specifically designed for the purpose. Ours has been doing a sterling job since the start of the year.

You may also need an additional heavy-duty/heat-resistant cable between the timer and immersion heater. This one is recommended.

Don't skimp on these things.

This looks good to me... LAP Digital Immersion Timer

 

[yessuz]

Be careful which time switch you use for an immersion heater. Most of the generic timers are not really rated for a 3 kW load for hours at a time. I would recommend this one as it's specifically designed for the purpose. Ours has been doing a sterling job since the start of the year.

You may also need an additional heavy-duty/heat-resistant cable between the timer and immersion heater. This one is recommended.

Don't skimp on these things.

well, if the wiring is already there (in the wall) it must be sufficient. then it's just a simple replacement of the switch.

I have been doing a few weeks.

With the boiler using gas for 30 minutes to heating the hot water, it used 8.5kwh.

The immersion heater which runs on and off for 3 hours overnight used 3kwh of electricity.

so 3 kwh of electricity is 22.5p off peak.
8.5 kwh gas is 6.29p/kWh, so 53.55p - twice :O

 

[ACarneiro]

well, if the wiring is already there (in the wall) it must be sufficient. then it's just a simple replacement of the switch.


so 3 kwh of electricity is 22.5p off peak.
8.5 kwh gas is 6.29p/kWh, so 53.55p - twice :O

That is a very low gas tariff. Most people will be above 10p/kWh which makes off-peak electrical heating even more compelling (for the first time ever!)
I've been doing it for weeks and seems got be working OK, although my 100A supply is getting pretty hammered and tight for capacity at cheap-o'clock now...

 

[yessuz]

That is a very low gas tariff. Most people will be above 10p/kWh which makes off-peak electrical heating even more compelling (for the first time ever!)
I've been doing it for weeks and seems got be working OK, although my 100A supply is getting pretty hammered and tight for capacity at cheap-o'clock now...

yeah.. my gas is up for the renewal soon....

 

[chemirocha]

Be careful which time switch you use for an immersion heater. Most of the generic timers are not really rated for a 3 kW load for hours at a time. I would recommend this one as it's specifically designed for the purpose. Ours has been doing a sterling job since the start of the year.

You may also need an additional heavy-duty/heat-resistant cable between the timer and immersion heater. This one is recommended.

Don't skimp on these things.

I'd second that. I would also add a word of caution if, like me, your immersion heater has a 3-pin plug on it, designed to be an emergency use only if the gas boiler fails.

A lot of 3-pin plugs and sockets, despite being rated for 13A continuous, will not cope with this over an extended period and may fail. Very few 3-pin timers or smart plugs will be able to handle the demand - see home automation forums for some very scary pictures of melted installations.

A 3kW immersion heater drawing 13A for several hours will highlight any weaknesses you may have in your wiring circuits. Although a modern, well installed ring circuit should cope, ideally you want a dedicated fused spur direct from the CU.

So, assuming you have a fused spur, you will want to replace the outlet with a timer specifically designed for switching a high current load. As scdoubleu said, don't skimp on this.

Given that this will be in operation overnight, when everyone is asleep, I would be very careful. At the very least, make sure your smoke alarms are working!

 

[scdoubleu]

well, if the wiring is already there (in the wall) it must be sufficient. then it's just a simple replacement of the switch.

The time-switch I linked to is not designed to replace a regular immersion switch on a back-box. I kept the original wall switch and mounted the timer nearby. Original cable wasn't long enough to split so the cable I also linked to was required.

I definitely wouldn't trust some random-jumble-of-letters Chinesium brand timeswitch from Amazon Marketplace.

 

[Jason71]

My hot water tank is currently heated by the gas boiler once a day. It also has an electric immersion heater as backup.

This thread has me thinking whether installing a timer and switching to heating via the immersion, off peak, might be worth it?

Anyone else doing this already?

I did it two weeks ago. but my tank has an immersion towards the bottom in addition to the one at the top. if you only have one at the top it is not really suitable for heating the whole tank just a bit at the top in case the boiler is down so not sure how well that will work.

 

[ME_UK]

Don't forget, if you decide to heat up the car in the morning, then it will use the mains electric not the battery - unless you unplug first. Maybe there's a way to turn this off, but I haven't yet found it. You're effectively running fan heaters and electrical elements from the peak rate if you forget......

 

[PITA]

Don't forget, if you decide to heat up the car in the morning, then it will use the mains electric not the battery - unless you unplug first. Maybe there's a way to turn this off, but I haven't yet found it. You're effectively running fan heaters and electrical elements from the peak rate if you forget......

... unless your Ev charging lead is connected to Powerwalls...

 

[yessuz]

Anyone tried to:
1) start preheat
2) unlock charge port?