Small things matter

[Joeboy]

Hi Joeboy, you're welcome. . I'm OK thanks, or as well as anyone with wits can be whilst watching our glorious leaders avoid tackling climate change

Good to hear, on our GL's? Best ignored and getting on with what we can ourselves. Keeps the anger levels down and optimism high!

[nowty]

You know what I mean

Think we all have anecdotal positives of thermal mass - how much real world, measured experience do we have ?

I have to say that my two storage heaters with a combined thermal capacity of around 15kWh has transformed the ability of my small 6kW heatpump (thermal output, runs on typically less than 2kW leccy) to heat a 1970s 4 bed detached house. Gas boiler still switched off.

Paying full price for leccy would be difficult, but the 6hrs of Octopus intelligent at 5p / kWh rivals gas prices if you can time shift it and storage heaters do that beautifully, whilst my batteries time shift the power required for the heatpump. I also have a 1kW leccy heated kitchen floor which last year I upgraded the underfloor insulation from 5cm to 10cm, that has made a big difference. I now have that switched on at the last hour of the cheap rate to add more cheap energy to the thermal mass which again helps.

[Stinsy]

You know what I mean

Think we all have anecdotal positives of thermal mass - how much real world, measured experience do we have ?

I have to say that my two storage heaters with a combined thermal capacity of around 15kWh has transformed the ability of my small 6kW heatpump (thermal output, runs on typically less than 2kW leccy) to heat a 1970s 4 bed detached house. Gas boiler still switched off.

Paying full price for leccy would be difficult, but the 6hrs of Octopus intelligent at 5p / kWh rivals gas prices if you can time shift it and storage heaters do that beautifully, whilst my batteries time shift the power required for the heatpump. I also have a 1kW leccy heated kitchen floor which last year I upgraded the underfloor insulation from 5cm to 10cm, that has made a big difference. I now have that switched on at the last hour of the cheap rate to add more cheap energy to the thermal mass which again helps.

Two questions:

1) How do you reconcile the cost of off-peak electric vs gas? I get that they’re closer now (I used to pay 3.4p per kWh for gas, went up to 4.37p last month) but gas is still cheaper than electric. I convince myself that my boiler cannot be as efficient as the manufacturer claims. I get that your heat pump is a no-brainier on cheap-rate and my garden office storage heater similar. But is cheap-rate resistive heating cost effective?

2) Have you found an easy way to manage the shifting nature of Intelligent Octopus? The reason to chose Go/Go-Faster over Agile has always been that you can set-and-forget all your various timers. Even when Agile was cheaper than Go/Go-Faster (seems like a long time ago) the shifting nature and complexity of living with it made it unattractive. All aspects of my system are designed with the principle that if I were incapacitated my instructions to the wife would be “Do nothing, it looks after itself”.

[Joeboy]

Frost on windscreens and grass this morning. Day 2 no GCH although it was close. Hive triggers at 16 deg, this morning the big room was at 16.4 degs. Going on Hive temp trace for the last week that would have been 15 degs and gas on if not for the TM. Away to collect my free building materials later this morning and then we'll start prepping for big Jenga.

If I can come close to doubling the current TM and then pass the SWMBO gaze it will i think offset the GCH until late Nov and hopefully perform a similar miracle at the other end of Winter. I should in theory (large guess) be able to cull around 8 weeks GCH annually from the current use.
Old gas use figure for Nov stands at 3,476kWh (2016), managed to get that down to 2,299kWh (2020), end of this month will be the first Nov with the WS operating.

[nowty]

You know what I mean

Think we all have anecdotal positives of thermal mass - how much real world, measured experience do we have ?

I have to say that my two storage heaters with a combined thermal capacity of around 15kWh has transformed the ability of my small 6kW heatpump (thermal output, runs on typically less than 2kW leccy) to heat a 1970s 4 bed detached house. Gas boiler still switched off.

Paying full price for leccy would be difficult, but the 6hrs of Octopus intelligent at 5p / kWh rivals gas prices if you can time shift it and storage heaters do that beautifully, whilst my batteries time shift the power required for the heatpump. I also have a 1kW leccy heated kitchen floor which last year I upgraded the underfloor insulation from 5cm to 10cm, that has made a big difference. I now have that switched on at the last hour of the cheap rate to add more cheap energy to the thermal mass which again helps.

Two questions:

1) How do you reconcile the cost of off-peak electric vs gas? I get that they’re closer now (I used to pay 3.4p per kWh for gas, went up to 4.37p last month) but gas is still cheaper than electric. I convince myself that my boiler cannot be as efficient as the manufacturer claims. I get that your heat pump is a no-brainier on cheap-rate and my garden office storage heater similar. But is cheap-rate resistive heating cost effective?

2) Have you found an easy way to manage the shifting nature of Intelligent Octopus? The reason to chose Go/Go-Faster over Agile has always been that you can set-and-forget all your various timers. Even when Agile was cheaper than Go/Go-Faster (seems like a long time ago) the shifting nature and complexity of living with it made it unattractive. All aspects of my system are designed with the principle that if I were incapacitated my instructions to the wife would be “Do nothing, it looks after itself”.

Stinsy, to answer your questions,

1) In the past I could not financially reconcile the cost of off peak leccy vs gas, although you could carbonwise. But now my gas is 4.2p / kWh and the off peak leccy is 5p / kWh. Given the inefficiencies of gas boilers the cost of resistive heating for me is practically identical so it is now cost effective. It also helps my relatively small heatpump work for longer into the heating season so the gas boiler can be turned off for longer. When the ripple wind turbine starts, the effective cost for me will go negative and arguably be zero carbon or even negative carbon if I don't use up all my generation quota.

2) The quick answer to your question is yes, just plug the EV in at 23:30 and its the same as the Go tariff but with 6 hours cheap rate instead of 4 hours.

Now the long explanation,

Everyday I get 5p / kWh for a FIXED 6 hour slot starting at 23:30 and finishing at 05:30, so thats 12 half hour slots. So in that respect its better than the Go or Go Faster tariffs. I don't need to change timers or anything.

The only difficulty with the tariff is if you plug in earlier in the evening from 5pm, the APP works out the best charging regime for the EV to suit Octopus but not me. But it does not change any of my fixed 12 half hour cheap slots (23:30 to 05:30) from cheap to peak rate. What it does do is decide not to charge the car in some of those cheap slots and may also choose to charge the car in some peak rate slots. But, if Octopus chooses to charge the car during any peak time slots, those peak time slots change to additional cheap rate slots, not just for the car but for the whole house. So it would normally be a win win, but in my case if I don't re-programme my battery inverter for any additional cheap slots, the first 6kW is coming out of my battery inverter and not the grid.

However, sometimes if its really cold, its nice to have some additional cheap slots earlier in the evening to run the heatpump, cook the dinner, etc.

[Joeboy]

I have to say that my two storage heaters with a combined thermal capacity of around 15kWh has transformed the ability of my small 6kW heatpump (thermal output, runs on typically less than 2kW leccy) to heat a 1970s 4 bed detached house. Gas boiler still switched off.

Paying full price for leccy would be difficult, but the 6hrs of Octopus intelligent at 5p / kWh rivals gas prices if you can time shift it and storage heaters do that beautifully, whilst my batteries time shift the power required for the heatpump. I also have a 1kW leccy heated kitchen floor which last year I upgraded the underfloor insulation from 5cm to 10cm, that has made a big difference. I now have that switched on at the last hour of the cheap rate to add more cheap energy to the thermal mass which again helps.

Two questions:

1) How do you reconcile the cost of off-peak electric vs gas? I get that they’re closer now (I used to pay 3.4p per kWh for gas, went up to 4.37p last month) but gas is still cheaper than electric. I convince myself that my boiler cannot be as efficient as the manufacturer claims. I get that your heat pump is a no-brainier on cheap-rate and my garden office storage heater similar. But is cheap-rate resistive heating cost effective?

2) Have you found an easy way to manage the shifting nature of Intelligent Octopus? The reason to chose Go/Go-Faster over Agile has always been that you can set-and-forget all your various timers. Even when Agile was cheaper than Go/Go-Faster (seems like a long time ago) the shifting nature and complexity of living with it made it unattractive. All aspects of my system are designed with the principle that if I were incapacitated my instructions to the wife would be “Do nothing, it looks after itself”.

Stinsy, to answer your questions,

1) In the past I could not financially reconcile the cost of off peak leccy vs gas, although you could carbonwise. But now my gas is 4.2p / kWh and the off peak leccy is 5p / kWh. Given the inefficiencies of gas boilers the cost of resistive heating for me is practically identical so it is now cost effective. It also helps my relatively small heatpump work for longer into the heating season so the gas boiler can be turned off for longer. When the ripple wind turbine starts, the effective cost for me will go negative and arguably be zero carbon or even negative carbon if I don't use up all my generation quota.

2) The quick answer to your question is yes, just plug the EV in at 23:30 and its the same as the Go tariff but with 6 hours cheap rate instead of 4 hours.

Now the long explanation,

Everyday I get 5p / kWh for a FIXED 6 hour slot starting at 23:30 and finishing at 05:30, so thats 12 half hour slots. So in that respect its better than the Go or Go Faster tariffs. I don't need to change timers or anything.

The only difficulty with the tariff is if you plug in earlier in the evening from 5pm, the APP works out the best charging regime for the EV to suit Octopus but not me. But it does not change any of my fixed 12 half hour cheap slots (23:30 to 05:30) from cheap to peak rate. What it does do is decide not to charge the car in some of those cheap slots and may also choose to charge the car in some peak rate slots. But, if Octopus chooses to charge the car during any peak time slots, those peak time slots change to additional cheap rate slots, not just for the car but for the whole house. So it would normally be a win win, but in my case if I don't re-programme my battery inverter for any additional cheap slots, the first 6kW is coming out of my battery inverter and not the grid.

However, sometimes if its really cold, its nice to have some additional cheap slots earlier in the evening to run the heatpump, cook the dinner, etc.

Cheers Nowty, I will refer to this post once the SMET2 is sorted and outputting once more

Collected some storage bricks this morning and had a crack at cutting the edges off to give full contact face to face. A 115mm diamond tipped disc on my little battery powered angle grinder did the trick. Messed about with a cob mix for the edges and currently baking dry my first 15kg block of thermal mass.

[Stinsy]

However, sometimes if its really cold, its nice to have some additional cheap slots earlier in the evening to run the heatpump, cook the dinner, etc.

I think we'd all like a few extra cheap-rate slots early in the evening this time of year! I don't know about you chaps but my batteries struggle to get me through the day when there is little-to-no solar to be found. The challenge is reprogramming the inverter-charger and smart-plugs every day...

[Joeboy]

Old v's new. The 'cob' being used is along the lines of thermal paste on a CPU heatsink.

[Joeboy]

The first 'official' line is in! Weighs 60 kg's. Have seen it peak at 170 degs on the inner blocks and around 30 deg below that at outer blocks. Plenty left to do, first step only.

GCH remains dormant.

[nowty]

The first 'official' line is in! Weighs 60 kg's. Have seen it peak at 170 degs on the inner blocks and around 30 deg below that at outer blocks. Plenty left to do, first step only.

GCH remains dormant.

I'd paint the front exposed face with some black heat resistant paint so it matches better. Might give you more buy in from SWMBO.