Octopus Agile

Slinky

I didn't do anything last time and got 2p. If it's sunny we'll be exporting then.

Newbie_John

It must make some sense. Maybe they realised that most typical cycles oven roast, dishwasher, washing machine etc. take 2h so if typical person starts at 1pm for 0p and then at 2pm for 23p (when the cost for Octopus is very low, like 2p) they will actually end up paying back for their "free electricity".. we can only guess.

NedS

Netexporter said:

Newbie_John said:

To get more confused 2-3pm is the cheapest about 5p, but now received an email saying that the 8p slot between 1-2pm is free* 😅

*free above typical usage

Yes, I've been scratching my head about the logic of that. Still, any cheap/free leccy is welcome. Mustn't look a gift cephalopod in the mouth.

I think they've standardised on the 1-2pm slot for the "free" extra usage sessions, rather than keep moving the times around based on what is cheapest on the day.

Doesn't look like we will be able to take advantage. Looking back, our average weekend 1-2pm usage is around 1kW, and it's sunny so we'd need to use our 3kW of solar generation first, on top of that 1kW average usage to benefit, which is just not going to happen. If it were raining and solar was non-existent, then we'd be in with a shout. Still, not complaining - I think it's a great initiative from Octopus, and we are already benefiting from 3-4h of good prices anyway.

NedS

Our average import price paid for August on Agile was 11.0p per kWh (cheapest monthly average since April, and half the Ofgem cap). If I exclude all the negative days where I have used more electricity than I otherwise would, thus artificially pulling down the unit price, my average cost comes in at 14.8p per kWh, but which does not then reflect those negatively priced days having been excluded. Hence, my real average is likely somewhere between the two.

Very happy with that.

MP1995

NedS said:

Our average import price paid for August on Agile was 11.0p per kWh (cheapest monthly average since April, and half the Ofgem cap). If I exclude all the negative days where I have used more electricity than I otherwise would, thus artificially pulling down the unit price, my average cost comes in at 14.8p per kWh, but which does not then reflect those negatively priced days having been excluded. Hence, my real average is likely somewhere between the two.

Very happy with that.

8.46p kwh here for August.

We have a little off grid solar (1kw) and 4kw battery storage running the tumbledryer, gym aircon/ofgice and electric outside cooking so that has made a difference as well.

Newbie_John

August was good, same here 8.7p an average, resulting £19.40 (without charge fee) - cheapest month of the year, now only up I guess

What do others here without gas and without ASHP use to efficiently heat the house with Agile?

So far I've been using smart switch operated heaters, but given up on them this year as I have learnt a lot about safety of such combination. Recently purchased: Philips Ceramic Fan Heater 5000 Series (used like new are on Amazon Warehouse for £65) and it's really good - no issues setting it up with 2g/5g wifi network, the app is great, a lot of safety features, good brand (unlike variety of Chineese tat on Amazon) and it looks nice too.

Spies

11.9p for the last two months for me, will be interesting come October when I get my ASHP installed

NedS

Newbie_John said:

What do others here without gas and without ASHP use to efficiently heat the house with Agile?

Before we had our ASHP installed, we used electric heaters whenever prices were cheap / negative to supplement our oil central heating. We have a 1.5kW oil filled radiator with a built-in timer which could be conveniently set during the night to turn on/off during any cheap/free 30min slots, and during the day we'd (ab)use our Rangemaster twin electric ovens (5.2kW combined) to pump some heat into our main living space. Electric fan heaters are also cheap to buy and convenient to plug in.

This will be our first winter with our ASHP, so it will be difficult to get into the habit of just leaving it to run (other than a set back during the 4-7pm peak), but I'm sure we will be bumping up the temps in the cheap/free slots.

Spies

NedS said:

Newbie_John said:

What do others here without gas and without ASHP use to efficiently heat the house with Agile?

Before we had our ASHP installed, we used electric heaters whenever prices were cheap / negative to supplement our oil central heating. We have a 1.5kW oil filled radiator with a built-in timer which could be conveniently set during the night to turn on/off during any cheap/free 30min slots, and during the day we'd (ab)use our Rangemaster twin electric ovens (5.2kW combined) to pump some heat into our main living space. Electric fan heaters are also cheap to buy and convenient to plug in.

This will be our first winter with our ASHP, so it will be difficult to get into the habit of just leaving it to run (other than a set back during the 4-7pm peak), but I'm sure we will be bumping up the temps in the cheap/free slots.

Do you boost your water between 1 and 2pm to get highest COP? As that's what I'm considering and also make use of peak solar power.

NedS

Spies said:

NedS said:

Newbie_John said:

What do others here without gas and without ASHP use to efficiently heat the house with Agile?

Before we had our ASHP installed, we used electric heaters whenever prices were cheap / negative to supplement our oil central heating. We have a 1.5kW oil filled radiator with a built-in timer which could be conveniently set during the night to turn on/off during any cheap/free 30min slots, and during the day we'd (ab)use our Rangemaster twin electric ovens (5.2kW combined) to pump some heat into our main living space. Electric fan heaters are also cheap to buy and convenient to plug in.

This will be our first winter with our ASHP, so it will be difficult to get into the habit of just leaving it to run (other than a set back during the 4-7pm peak), but I'm sure we will be bumping up the temps in the cheap/free slots.

Do you boost your water between 1 and 2pm to get highest COP? As that's what I'm considering and also make use of peak solar power.

Firstly, I'm not overly fixated with obtaining the highest COP (some are, and just want to top the highly competitive league tables of COP!) - which is just an efficiency ratio. What is more important to me is to minimise my bill, even if that means my COP is a little lower (if that makes sense).

At the moment we are only heating our DHW once daily. There are multiple factors to consider that interplay:

1. All else being equal, we would like to select the cheapest 30min Agile slot in which to run the DHW cycle.

2. The ASHP will be more efficient at the warmest part of the day, thus reducing the amount of energy required to run the cycle. That may be a trade off with (1)

3. We have solar (but no batteries). SEG is 15p, so if the Agile price is more than the SEG price, we want to maximise solar usage (run when sunny) but if the Agile price is cheap, we want to import at that price and not use solar, so it may be cheaper to run during a cheap overnight slot to guarantee use of the lower Agile import price.

4. If prices are very cheap / negative, do we then heat the water hotter than normal to store a little energy in the hope that we start from a higher starting temp tomorrow and do not need to input as much energy tomorrow at what may be higher prices.

5. When prices are negative, lets switch on the immersion and run a legionella cycle for good measure.

Given the above, I tend to run my DHW cycle between 1pm and 4pm most afternoons, other than when negative overnight. Once we'd had our new bathroom completed, I'm pretty sure we will be running 2 cycles per day, so that will most likely just be the cheapest overnight and afternoon slots for the two runs.

Edit: It is typically more efficient to allow the DHW to cool and reheat once per day (or more if required), than to run the ASHP on constant demand, reheating whenever the tank temp drops by a set amount (say 5C). Ideally you want the tank temp to have cooled as much as possible so the heat pump gets to run for longer to reheat it, making the run more efficient. IOW, it's going to be cheaper overall to do one long run per day (1.5kWh) than two shorter 1.0kWh runs.