Efficient Gas Boiler and Climate Control
@showpiece.bsky.social
Goals:
1. Climate comfort - where you can’t tell whether heating is on or off and you feel comfortable
2. Efficient boiler to minimise costs and pollution
GitHub:
https://github.com/Alexwijn/SAT/discussions/40
1. Climate comfort - where you can’t tell whether heating is on or off and you feel comfortable
2. Efficient boiler to minimise costs and pollution
GitHub:
https://github.com/Alexwijn/SAT/discussions/40
Pinned
Efficient gas boiler [Ideal Logic Heat H24] discussion:
github.com/Alexwijn/SAT...
Emoncms dashboard:
emoncms.org/app/view?nam...
Grafana dashboard:
gasboiler.grafana.net/public-dashb...
github.com/Alexwijn/SAT...
Emoncms dashboard:
emoncms.org/app/view?nam...
Grafana dashboard:
gasboiler.grafana.net/public-dashb...
9/ Net: increased emitter capacity (+108%), which enabled much lower CH flow/return temps and reduced CH run-time. At the same time, gas unit price dropped. Together, that pushed winter and annual gas spend down.
@openenergymon.bsky.social @chiefgeekad.bsky.social @joalsop.bsky.social
@openenergymon.bsky.social @chiefgeekad.bsky.social @joalsop.bsky.social
January 15, 2026 at 8:21 AM
9/ Net: increased emitter capacity (+108%), which enabled much lower CH flow/return temps and reduced CH run-time. At the same time, gas unit price dropped. Together, that pushed winter and annual gas spend down.
@openenergymon.bsky.social @chiefgeekad.bsky.social @joalsop.bsky.social
@openenergymon.bsky.social @chiefgeekad.bsky.social @joalsop.bsky.social
8/ Whole-year household gas (includes cooking):
2024: 13,625.66 kWh, £985.69
2025: 11,962.23 kWh, £775.80
That is -12.2% kWh and -21.3% cost. Implied £/kWh also fell (~7.23p -> ~6.49p).
2024: 13,625.66 kWh, £985.69
2025: 11,962.23 kWh, £775.80
That is -12.2% kWh and -21.3% cost. Implied £/kWh also fell (~7.23p -> ~6.49p).
January 15, 2026 at 8:21 AM
8/ Whole-year household gas (includes cooking):
2024: 13,625.66 kWh, £985.69
2025: 11,962.23 kWh, £775.80
That is -12.2% kWh and -21.3% cost. Implied £/kWh also fell (~7.23p -> ~6.49p).
2024: 13,625.66 kWh, £985.69
2025: 11,962.23 kWh, £775.80
That is -12.2% kWh and -21.3% cost. Implied £/kWh also fell (~7.23p -> ~6.49p).
7/ Boiler running cost snapshot (gas only, Tracker, 93 days):
2024-10-12 to 2025-01-12: 5075 kWh, £330 incl standing charge (~£3.55/day)
2025-10-12 to 2026-01-12: 4712 kWh, £257 (~£2.77/day)
2024-10-12 to 2025-01-12: 5075 kWh, £330 incl standing charge (~£3.55/day)
2025-10-12 to 2026-01-12: 4712 kWh, £257 (~£2.77/day)
January 15, 2026 at 8:21 AM
7/ Boiler running cost snapshot (gas only, Tracker, 93 days):
2024-10-12 to 2025-01-12: 5075 kWh, £330 incl standing charge (~£3.55/day)
2025-10-12 to 2026-01-12: 4712 kWh, £257 (~£2.77/day)
2024-10-12 to 2025-01-12: 5075 kWh, £330 incl standing charge (~£3.55/day)
2025-10-12 to 2026-01-12: 4712 kWh, £257 (~£2.77/day)
6/ CH energy over the window (DHW excluded):
Heat delivered 4104.6 -> 3306.2 kWh (-19.5%)
Gas used 4331.1 -> 3640.4 kWh (-16.0%)
Heat delivered 4104.6 -> 3306.2 kWh (-19.5%)
Gas used 4331.1 -> 3640.4 kWh (-16.0%)
January 15, 2026 at 8:21 AM
6/ CH energy over the window (DHW excluded):
Heat delivered 4104.6 -> 3306.2 kWh (-19.5%)
Gas used 4331.1 -> 3640.4 kWh (-16.0%)
Heat delivered 4104.6 -> 3306.2 kWh (-19.5%)
Gas used 4331.1 -> 3640.4 kWh (-16.0%)
5/ Runtime: average CH ON time dropped from 8.80 h/day -> 6.87 h/day (-1.93 h/day, about -22%). Less time calling for heat while holding the same mean room temp but increased speed of the circulation pump (medium).
January 15, 2026 at 8:21 AM
5/ Runtime: average CH ON time dropped from 8.80 h/day -> 6.87 h/day (-1.93 h/day, about -22%). Less time calling for heat while holding the same mean room temp but increased speed of the circulation pump (medium).
4/ Comfort and weather were basically unchanged (means):
Room 20.5°C -> 20.5°C
Outside 6.6°C -> 6.5°C
Room 20.5°C -> 20.5°C
Outside 6.6°C -> 6.5°C
January 15, 2026 at 8:21 AM
4/ Comfort and weather were basically unchanged (means):
Room 20.5°C -> 20.5°C
Outside 6.6°C -> 6.5°C
Room 20.5°C -> 20.5°C
Outside 6.6°C -> 6.5°C
3/ CH temperatures (means, DHW excluded):
Flow 33.0°C -> 26.2°C (-6.8°C)
Return 28.5°C -> 23.1°C (-5.4°C)
System DeltaT 4.5°C -> 3.1°C (-1.4°C)
Flow 33.0°C -> 26.2°C (-6.8°C)
Return 28.5°C -> 23.1°C (-5.4°C)
System DeltaT 4.5°C -> 3.1°C (-1.4°C)
January 15, 2026 at 8:21 AM
3/ CH temperatures (means, DHW excluded):
Flow 33.0°C -> 26.2°C (-6.8°C)
Return 28.5°C -> 23.1°C (-5.4°C)
System DeltaT 4.5°C -> 3.1°C (-1.4°C)
Flow 33.0°C -> 26.2°C (-6.8°C)
Return 28.5°C -> 23.1°C (-5.4°C)
System DeltaT 4.5°C -> 3.1°C (-1.4°C)
2/ Hardware: total radiator output at DeltaT50 (BS EN 442) went from 11.724 kW -> 22.028 kW (+87.9%). With fans: 24.367 kW (+107.8%). More emitter capacity lets you run cooler water.
January 15, 2026 at 8:21 AM
2/ Hardware: total radiator output at DeltaT50 (BS EN 442) went from 11.724 kW -> 22.028 kW (+87.9%). With fans: 24.367 kW (+107.8%). More emitter capacity lets you run cooler water.
1/ Gas boiler + upgraded radiators (plus small fans). Summary using CH-only stats (DHW excluded) for performance, and boiler-only gas costs for pricing. Two comparable winter windows + whole-year gas totals. @janrosenow.bsky.social
January 15, 2026 at 8:21 AM
1/ Gas boiler + upgraded radiators (plus small fans). Summary using CH-only stats (DHW excluded) for performance, and boiler-only gas costs for pricing. Two comparable winter windows + whole-year gas totals. @janrosenow.bsky.social
Electricity / Gas Unit Cost Ratio Comparison
[30 days, 16 Dec 2025 – 14 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.91×
Electricity: £0.2553
Gas: £0.0520
Mean:
Spark-Gap Tracker: 4.91×
Electricity: £0.2380
Gas: £0.0485
[30 days, 16 Dec 2025 – 14 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.91×
Electricity: £0.2553
Gas: £0.0520
Mean:
Spark-Gap Tracker: 4.91×
Electricity: £0.2380
Gas: £0.0485
January 15, 2026 at 5:06 AM
Electricity / Gas Unit Cost Ratio Comparison
[30 days, 16 Dec 2025 – 14 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.91×
Electricity: £0.2553
Gas: £0.0520
Mean:
Spark-Gap Tracker: 4.91×
Electricity: £0.2380
Gas: £0.0485
[30 days, 16 Dec 2025 – 14 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.91×
Electricity: £0.2553
Gas: £0.0520
Mean:
Spark-Gap Tracker: 4.91×
Electricity: £0.2380
Gas: £0.0485
January 15, 2026 at 5:05 AM
Cost, Energy and Comfort Comparison
[30 Days | 16 Dec 25 to 14 Jan 26]
Boiler (Tracker) was cheaper by £31.91 (22.2 %) vs Heat Pump (Agile), or £22.95 after offsetting £8.96 gas stand. charge (30 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[30 Days | 16 Dec 25 to 14 Jan 26]
Boiler (Tracker) was cheaper by £31.91 (22.2 %) vs Heat Pump (Agile), or £22.95 after offsetting £8.96 gas stand. charge (30 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
January 15, 2026 at 5:05 AM
Cost, Energy and Comfort Comparison
[30 Days | 16 Dec 25 to 14 Jan 26]
Boiler (Tracker) was cheaper by £31.91 (22.2 %) vs Heat Pump (Agile), or £22.95 after offsetting £8.96 gas stand. charge (30 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[30 Days | 16 Dec 25 to 14 Jan 26]
Boiler (Tracker) was cheaper by £31.91 (22.2 %) vs Heat Pump (Agile), or £22.95 after offsetting £8.96 gas stand. charge (30 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
Upgrading radiators reduced CH heat demand by 19.45%
2024 to 2025: 4104.6 kWh
2025 to 2026: 3306.2 kWh
Average outside conditions almost identical 💚
2024 to 2025: 4104.6 kWh
2025 to 2026: 3306.2 kWh
Average outside conditions almost identical 💚
January 14, 2026 at 9:16 PM
Upgrading radiators reduced CH heat demand by 19.45%
2024 to 2025: 4104.6 kWh
2025 to 2026: 3306.2 kWh
Average outside conditions almost identical 💚
2024 to 2025: 4104.6 kWh
2025 to 2026: 3306.2 kWh
Average outside conditions almost identical 💚
Electricity / Gas Unit Cost Ratio Comparison
[19 days, 26 Dec 2025 – 13 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.89×
Electricity: £0.2467
Gas: £0.0505
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2415
Gas: £0.0488
[19 days, 26 Dec 2025 – 13 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.89×
Electricity: £0.2467
Gas: £0.0505
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2415
Gas: £0.0488
January 14, 2026 at 6:50 AM
Electricity / Gas Unit Cost Ratio Comparison
[19 days, 26 Dec 2025 – 13 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.89×
Electricity: £0.2467
Gas: £0.0505
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2415
Gas: £0.0488
[19 days, 26 Dec 2025 – 13 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.89×
Electricity: £0.2467
Gas: £0.0505
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2415
Gas: £0.0488
January 14, 2026 at 6:49 AM
Cost, Energy and Comfort Comparison
[19 Days | 26 Dec 25 to 13 Jan 26]
Boiler (Tracker) was cheaper by £26.27 (25.4 %) vs Heat Pump (Agile), or £20.59 after offsetting £5.67 gas stand. charge (19 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[19 Days | 26 Dec 25 to 13 Jan 26]
Boiler (Tracker) was cheaper by £26.27 (25.4 %) vs Heat Pump (Agile), or £20.59 after offsetting £5.67 gas stand. charge (19 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
January 14, 2026 at 6:49 AM
Cost, Energy and Comfort Comparison
[19 Days | 26 Dec 25 to 13 Jan 26]
Boiler (Tracker) was cheaper by £26.27 (25.4 %) vs Heat Pump (Agile), or £20.59 after offsetting £5.67 gas stand. charge (19 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[19 Days | 26 Dec 25 to 13 Jan 26]
Boiler (Tracker) was cheaper by £26.27 (25.4 %) vs Heat Pump (Agile), or £20.59 after offsetting £5.67 gas stand. charge (19 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
Electricity / Gas Unit Cost Ratio Comparison
[18 days, 26 Dec 2025 – 12 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.81×
Electricity: £0.2316
Gas: £0.0482
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2412
Gas: £0.0487
[18 days, 26 Dec 2025 – 12 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.81×
Electricity: £0.2316
Gas: £0.0482
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2412
Gas: £0.0487
January 13, 2026 at 5:05 AM
Electricity / Gas Unit Cost Ratio Comparison
[18 days, 26 Dec 2025 – 12 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.81×
Electricity: £0.2316
Gas: £0.0482
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2412
Gas: £0.0487
[18 days, 26 Dec 2025 – 12 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.81×
Electricity: £0.2316
Gas: £0.0482
Mean:
Spark-Gap Tracker: 4.95×
Electricity: £0.2412
Gas: £0.0487
January 13, 2026 at 5:05 AM
Cost, Energy and Comfort Comparison
[18 Days | 26 Dec 25 to 12 Jan 26]
Boiler (Tracker) was cheaper by £26.21 (26.2 %) vs Heat Pump (Agile), or £20.83 after offsetting £5.38 gas stand. charge (18 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[18 Days | 26 Dec 25 to 12 Jan 26]
Boiler (Tracker) was cheaper by £26.21 (26.2 %) vs Heat Pump (Agile), or £20.83 after offsetting £5.38 gas stand. charge (18 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
January 13, 2026 at 5:05 AM
Cost, Energy and Comfort Comparison
[18 Days | 26 Dec 25 to 12 Jan 26]
Boiler (Tracker) was cheaper by £26.21 (26.2 %) vs Heat Pump (Agile), or £20.83 after offsetting £5.38 gas stand. charge (18 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[18 Days | 26 Dec 25 to 12 Jan 26]
Boiler (Tracker) was cheaper by £26.21 (26.2 %) vs Heat Pump (Agile), or £20.83 after offsetting £5.38 gas stand. charge (18 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
What's a true "Zero Disrupt / Express" heat pump installation? A HYBRID install: boiler + heat pump. Minimal disruption, no performance worries, and 80% less gas. Add it to the scheme💙 @betatalk.bsky.social @janrosenow.bsky.social @chiefgeekad.bsky.social @octopus.energy @edfenergy.com
To make the switch to clean energy easier, we should aim for lower electricity prices, not higher ones. Lower electricity prices would encourage more people to use heat pumps 💚
Cost, Energy and Comfort Comparison
[17 Days | 26 Dec 25 to 11 Jan 26]
Boiler (Tracker) was cheaper by £25.93 (26.7 %) vs Heat Pump (Agile), or £20.85 after offsetting £5.08 gas stand. charge (17 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[17 Days | 26 Dec 25 to 11 Jan 26]
Boiler (Tracker) was cheaper by £25.93 (26.7 %) vs Heat Pump (Agile), or £20.85 after offsetting £5.08 gas stand. charge (17 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
January 12, 2026 at 2:40 PM
What's a true "Zero Disrupt / Express" heat pump installation? A HYBRID install: boiler + heat pump. Minimal disruption, no performance worries, and 80% less gas. Add it to the scheme💙 @betatalk.bsky.social @janrosenow.bsky.social @chiefgeekad.bsky.social @octopus.energy @edfenergy.com
I can see @octopus.energy as the candidate 💚
January 12, 2026 at 9:05 AM
I can see @octopus.energy as the candidate 💚
Heat Pump Plus at a flat 15p/kWh was class-leading. Hopefully there will be a similar deal available soon @janrosenow.bsky.social
www.ovoenergy.com/heat-pump-plus
www.ovoenergy.com/heat-pump-plus
January 12, 2026 at 8:57 AM
Heat Pump Plus at a flat 15p/kWh was class-leading. Hopefully there will be a similar deal available soon @janrosenow.bsky.social
www.ovoenergy.com/heat-pump-plus
www.ovoenergy.com/heat-pump-plus
To make the switch to clean energy easier, we should aim for lower electricity prices, not higher ones. Lower electricity prices would encourage more people to use heat pumps 💚
Cost, Energy and Comfort Comparison
[17 Days | 26 Dec 25 to 11 Jan 26]
Boiler (Tracker) was cheaper by £25.93 (26.7 %) vs Heat Pump (Agile), or £20.85 after offsetting £5.08 gas stand. charge (17 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
[17 Days | 26 Dec 25 to 11 Jan 26]
Boiler (Tracker) was cheaper by £25.93 (26.7 %) vs Heat Pump (Agile), or £20.85 after offsetting £5.08 gas stand. charge (17 d × £0.299)🥇🎉
Prices based on @octopus.energy tariffs 💚
January 12, 2026 at 8:46 AM
To make the switch to clean energy easier, we should aim for lower electricity prices, not higher ones. Lower electricity prices would encourage more people to use heat pumps 💚
Electricity / Gas Unit Cost Ratio Comparison
[17 days, 26 Dec 2025 – 11 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.92×
Electricity: £0.2377
Gas: £0.0483
Mean:
Spark-Gap Tracker: 4.96×
Electricity: £0.2418
Gas: £0.0487
[17 days, 26 Dec 2025 – 11 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.92×
Electricity: £0.2377
Gas: £0.0483
Mean:
Spark-Gap Tracker: 4.96×
Electricity: £0.2418
Gas: £0.0487
January 12, 2026 at 5:05 AM
Electricity / Gas Unit Cost Ratio Comparison
[17 days, 26 Dec 2025 – 11 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.92×
Electricity: £0.2377
Gas: £0.0483
Mean:
Spark-Gap Tracker: 4.96×
Electricity: £0.2418
Gas: £0.0487
[17 days, 26 Dec 2025 – 11 Jan 2026]
Yesterday:
Spark-Gap Tracker: 4.92×
Electricity: £0.2377
Gas: £0.0483
Mean:
Spark-Gap Tracker: 4.96×
Electricity: £0.2418
Gas: £0.0487
January 12, 2026 at 5:05 AM