[i3S]

The switch to Octopus completes in a couple of days and then onto the Agile tariff a few days later. I feel slightly disappointed in myself that I’m actually quite excited.

My intention is that we exploit the advance knowledge of cheaper rates as fully as we can. We both work from home, so that which doesn’t have a timer or smart functionality can be tuned on manually.

To that end, our central heating is a wet underfloor system married to an air source heat pump. Upstairs the same system supplies traditional wall radiators. We have Tado smart room thermostats.

It takes a while and a lot of kWhs for the heat to come through the screed floor from absolute cold, so the advice from the manufacturers (Joule & Samsung) is to keep the house at a constant temperature.
Stats are all set to 19 which works well for us.

So, currently the system turns on and off when it needs to regardless of time.

Does anyone here with Agile have a similar heating setup perhaps?

Given Agile offers advance knowledge of variable rates at half hourly intervals within any 24 hour period, have you found it’s cheaper to set up your stats so the heating can only come on at certain times?

Or, given such a setup could mean the system might be starting from a colder temperature, each time it’s allowed to fire up, have you found it’s having to draw that more power to reach the demanded temperature that it negates any saving over running it so the house is at a constant temperature?

The same question also applies to the hot water really. The same system also heats the water to a constant 48°. I’m wondering if it’s worth setting that up on the timer instead, balancing around cost and demand times for hot water.

Obviously, I could set the whole system up each day to only draw power during Plunge rates.....But pretty soon I’d have to invest all the savings I’d made into another house and a good divorce lawyer.

 

[dk6780]

We also have a wet UFH system with a 300 litre buffer tank with twin immersion heaters as an intermediary. However ours is gas fired via Octopus Tracker which currently has very low rates. This allows us to keep the water temperature relatively constant but to switch between Gas and electric as Agile rates vary. To maximize the benefits I have increased the range of temperature fluctuations that the Gas allows from 5C to 15C which has made little difference to the floor temperature but maximises the electricity usage at low rates. Note though that this has little effect on the water return temperature so clearly the flow rates through the floor are being varied more than normal.
I'm not sure how this is of benefit to you given the efficiency issues of operating the ASHP outside of its ideal temperatures and if you don't have an intermediate store.

 

[donald]

... ours is gas fired via Octopus Tracker which currently has very low rates. ...

Quick question, where do you see those rates for the day, and historically?

Maybe I might flip occasionally between Agile and Tracker, it is active the next day, so the web says.

 

[RunningStrong]

I don't have such a setup but a friend does and he's trying to get to grips with it himself.

My suggestion is to use the thermal mass of the floor during the lowest prices to boost the temperature and effectively create a thermal store. So instead of running a constant 19C, you could run at 21C during any negative pricing. Even if that means you're opening windows for a bit of cooling, you're still increasing the thermal mass in the slab. Ideally, you would do this overnight and with just the downstairs slab.

 

[KenB]

Heat Pumps are about small capacity running for long times if not permantly unlike a gas boiler of much higher capacity running for a much shorter time. This therefore does not tie in well with Agile playing. I would be just looking to make sure it does not come on at the peak time. If you were just using HP for HW then maybe.

 

[donald]

Heat Pumps are about small capacity running for long times if not permantly unlike a gas boiler of much higher capacity running for a much shorter time. This therefore does not tie in well with Agile playing. I would be just looking to make sure it does not come on at the peak time. If you were just using HP for HW then maybe.

If you look at Agile simply as a 'cheap plan, except 4PM to 7PM' then it would probably work well for storage-type heaters? Just turn it off 4-7 and I think you'd be quids in.

(My referral in my signature!! )

 

[i3S]

Heat Pumps are about small capacity running for long times if not permantly unlike a gas boiler of much higher capacity running for a much shorter time. This therefore does not tie in well with Agile playing. I would be just looking to make sure it does not come on at the peak time. If you were just using HP for HW then maybe.

This seemed to me to be the best way forward too.

The tank does have a hot water buffer tank and we only use the pump to heat it. The immersion heater’s never used.

 

[i3S]

I don't have such a setup but a friend does and he's trying to get to grips with it himself.

My suggestion is to use the thermal mass of the floor during the lowest prices to boost the temperature and effectively create a thermal store. So instead of running a constant 19C, you could run at 21C during any negative pricing. Even if that means you're opening windows for a bit of cooling, you're still increasing the thermal mass in the slab. Ideally, you would do this overnight and with just the downstairs slab.

This and @KenB’s suggestion to focus on not allowing the heating/water to come in peak sound like they’d work best.

21° is still a comfortable heat with windows closed. The house is pretty efficient so that residual heat would likely circulate for some time.

 

[RunningStrong]

21° is still a comfortable heat with windows closed. The house is pretty efficient so that residual heat would likely circulate for some time.

I'd be melting at 21C lol

 

[i3S]

I'd be melting at 21C lol

😬

 

[dk6780]

Quick question, where do you see those rates for the day, and historically?

Maybe I might flip occasionally between Agile and Tracker, it is active the next day, so the web says.

I don't think that you can switch between Agile and Tracker that easily. An explanation of how Tracker is calculated is available

Octopus Energy

I'm on it because it is better value than the gas variable rate and there is no "Agile" for gas at present.

 

[Edd Beesley]

The switch to Octopus completes in a couple of days and then onto the Agile tariff a few days later. I feel slightly disappointed in myself that I’m actually quite excited.

My intention is that we exploit the advance knowledge of cheaper rates as fully as we can. We both work from home, so that which doesn’t have a timer or smart functionality can be tuned on manually.

To that end, our central heating is a wet underfloor system married to an air source heat pump. Upstairs the same system supplies traditional wall radiators. We have Tado smart room thermostats.

It takes a while and a lot of kWhs for the heat to come through the screed floor from absolute cold, so the advice from the manufacturers (Joule & Samsung) is to keep the house at a constant temperature.
Stats are all set to 19 which works well for us.

So, currently the system turns on and off when it needs to regardless of time.

Does anyone here with Agile have a similar heating setup perhaps?

Given Agile offers advance knowledge of variable rates at half hourly intervals within any 24 hour period, have you found it’s cheaper to set up your stats so the heating can only come on at certain times?

Or, given such a setup could mean the system might be starting from a colder temperature, each time it’s allowed to fire up, have you found it’s having to draw that more power to reach the demanded temperature that it negates any saving over running it so the house is at a constant temperature?

The same question also applies to the hot water really. The same system also heats the water to a constant 48°. I’m wondering if it’s worth setting that up on the timer instead, balancing around cost and demand times for hot water.

Obviously, I could set the whole system up each day to only draw power during Plunge rates.....But pretty soon I’d have to invest all the savings I’d made into another house and a good divorce lawyer.

You're over thinking it - just don't run it between 4PM and 7PM.

 

[Kingpleb1]

I'd ask the manufacturer if there is a way to activate it at all during E7 or E10 cycles. If there is and all you have to do is supply voltage to a connector on the unit then a smart plug like what's been done by a member here with a Zappi would be perfect.

 

[i3S]

You're over thinking it - just don't run it between 4PM and 7PM.

If one wants to limit ones savings, sure. Plenty of time on my hands to try different options and see what can actually be achieved.

 

[Edd Beesley]

I'd ask the manufacturer if there is a way to activate it at all during E7 or E10 cycles. If there is and all you have to do is supply voltage to a connector on the unit then a smart plug like what's been done by a member here with a Zappi would be perfect.

With Agile it's pretty much E21, only 4-7PM have materially higher rates.

 

[Edd Beesley]

If one wants to limit ones savings, sure. Plenty of time on my hands to try different options and see what can actually be achieved.

OK you're going to spend hours chasing pennies though!

 

[Kingpleb1]

With Agile it's pretty much E21, only 4-7PM have materially higher rates.

True, but it's more like 7p/kWh where as I'm tight and would rather do it at below 4p/kWh or even less us possible

 

[i3S]

OK you're going to spend hours chasing pennies though!

“Hours”, probably not. Current consumption runs to about £1,500 a year at the mo. Every bit of cash I’m not giving to a utility firm is a win in my book.

 

[Peter Devon]

Quick question, where do you see those rates for the day, and historically?

Octopus Energy see How is the price of the Octopus Tracker calculated?
For electricity, wholesale costs are based on the Nordpool day ahead auction price. To find the latest figure, follow the previous link, set the currency to “GBP” and convert the price to kWh by dividing by 1,000.

For gas, wholesale costs are based on the Marex Spectron Day-Ahead Index. To find the latest figure, download the CSV from the previous link, and open it in a spreadsheet program such as Microsoft Excel or Google Sheets. Take the “Average” number for the most recent entry where IndexName is “NBP All Day D.A” (National Balancing Point, All Day, Day Ahead).

I collect the data and put the figures on my website. Nordpool is designed to prevent data scraping as well as forbidding it. I collect the data each day from Octopus by automatically reading my account.
The gas data can be scraped from Marex.

 

[Rowley]

Someone else said above to speak to your manufacturer/fitter. I did that as its the hot water heat that uses the most electricity so I asked if I could zone that out between 1600 and 1900. There sure is a way to do that and he led me through the setup over the phone. Now I have two times that the hot water will be on, one early morning and one evening. The actual heating side of is uses very little electricity (for me around 700w when at running temp) so I leave that on 24/7 365 days of the year. I have solar too which covers most/all of that depending on the time of year. Worth an ask, and if your system is compatible, very easy to set up