Cost, Energy and Comfort Comparison [13 Days | 24 May 26 to 5 Jun 26] Boiler (Fixed) was cheaper by £1.32 (12.8 %) vs Heat Pump (Agile), or £-2.50 after offsetting £3.81 gas stand. charge (13 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [62 Days | 5 Apr 26 to 5 Jun 26] Today 8.80 kWh; import saved £1.39 + export earned £0.36 Rates 25.7p import; 12.0p export Total 501.24 kWh; £105.53 total return (£1.70/day) Payback £684.89 left; 13.4% recovered; break-even 11 Aug 2027

Cost, Energy and Comfort Comparison [12 Days | 24 May 26 to 4 Jun 26] Boiler (Fixed) was cheaper by £0.79 (8.6 %) vs Heat Pump (Agile), or £-2.73 after offsetting £3.52 gas stand. charge (12 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [61 Days | 5 Apr 26 to 4 Jun 26] Today 5.90 kWh; import saved £0.99 + export earned £0.11 Rates 20.9p import; 12.0p export Total 492.44 kWh; £103.78 total return (£1.70/day) Payback £686.64 left; 13.1% recovered; break-even 11 Aug 2027

Cost, Energy and Comfort Comparison [11 Days | 24 May 26 to 3 Jun 26] Boiler (Fixed) was cheaper by £0.47 (5.7 %) vs Heat Pump (Cosy), or £-2.76 after offsetting £3.23 gas stand. charge (11 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [60 Days | 5 Apr 26 to 3 Jun 26] Today 7.55 kWh; import saved £0.92 + export earned £0.43 Rates 25.7p import; 12.0p export Total 486.54 kWh; £102.68 total return (£1.71/day) Payback £687.74 left; 13.0% recovered; break-even 8 Aug 2027

Cost, Energy and Comfort Comparison [10 Days | 24 May 26 to 2 Jun 26] Boiler (Fixed) was cheaper by £0.19 (2.5 %) vs Heat Pump (Cosy), or £-2.75 after offsetting £2.93 gas stand. charge (10 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [59 Days | 5 Apr 26 to 2 Jun 26] Today 5.42 kWh; import saved £0.85 + export earned £0.24 Rates 27.0p import; 12.0p export Total 478.99 kWh; £101.33 total return (£1.72/day) Payback £689.09 left; 12.8% recovered; break-even 7 Aug 2027

Cost, Energy and Comfort Comparison [31 Days | 1 May 26 to 31 May 26] Actual: boiler £25.44 vs Agile HP £43.64 (£18.20 cheaper). Solar DHW: 31.5kWh tank heat ≈45.7kWh modeled gas input (1.45x). No-solar boiler ≈£28.1; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [58 Days | 5 Apr 26 to 1 Jun 26] Today 3.23 kWh; import saved £0.81 + export earned £0.01 Rates 26.7p import; 12.0p export Total 473.58 kWh; £100.25 total return (£1.73/day) Payback £690.17 left; 12.7% recovered; break-even 5 Aug 2027

Cost, Energy and Comfort Comparison [92 Days | 1 Mar 26 to 31 May 26] Actual: boiler £149.44 vs Agile HP £248.31 (£98.87 cheaper). Solar DHW: 170.5kWh tank heat ≈247.2kWh modeled gas input (1.45x). No-solar boiler ≈£163.8; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [57 Days | 5 Apr 26 to 31 May 26] Today 5.19 kWh; import saved £1.29 + export earned £0.02 Rates 26.0p import; 12.0p export Total 470.34 kWh; £99.42 total return (£1.74/day) Payback £691.00 left; 12.6% recovered; break-even 3 Aug 2027

Not having solar and a battery is starting to feel like shopping without a supermarket loyalty card. The “normal” price is becoming the one you only get when you can generate, store and shift your own energy. The default energy deal is becoming the expensive one.

Cost, Energy and Comfort Comparison [252 Days | 24 Apr 24 to 31 Dec 24] Boiler (Tracker) was cheaper by £33.61 (7.7 %) vs Heat Pump (Agile), or £-35.61 after offsetting £69.22 gas stand. charge (252 d × £0.275)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [56 Days | 5 Apr 26 to 30 May 26] Today 11.57 kWh; import saved £3.07 + export earned £0.42 Rates 26.5p import; 12.0p export Total 465.15 kWh; £113.66 total return (£2.03/day) Payback £676.76 left; 14.4% recovered; break-even 15 Jun 2027

Cost, Energy and Comfort Comparison [9 Days | 21 May 26 to 29 May 26] Boiler (Fixed) was cheaper by £0.33 (4.6 %) vs Heat Pump (Agile), or £-2.31 after offsetting £2.64 gas stand. charge (9 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [55 Days | 5 Apr 26 to 29 May 26] Today 10.02 kWh; import saved £2.61 + export earned £0.39 Rates 26.1p import; 12.0p export Total 453.58 kWh; £110.17 total return (£2.00/day) Payback £680.25 left; 13.9% recovered; break-even 17 Jun 2027

Solar payback: [54 Days | 5 Apr 26 to 28 May 26] Today 9.61 kWh; import saved £2.46 + export earned £0.44 Rates 25.6p import; 12.0p export Total 443.57 kWh; £107.17 total return (£1.98/day) Payback £683.25 left; 13.6% recovered; break-even 18 Jun 2027

Cost, Energy and Comfort Comparison [7 Days | 21 May 26 to 27 May 26] Boiler (Fixed) was cheaper by £2.72 (32.4 %) vs Heat Pump (Intelligent Flux), or £0.66 after offsetting £2.05 gas stand. charge (7 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [53 Days | 5 Apr 26 to 27 May 26] Today 11.67 kWh; import saved £3.06 + export earned £0.69 Rates 26.2p import; 12.0p export Total 433.96 kWh; £104.27 total return (£1.97/day) Payback £686.15 left; 13.2% recovered; break-even 20 Jun 2027

Cost, Energy and Comfort Comparison [6 Days | 21 May 26 to 26 May 26] Boiler (Fixed) was cheaper by £2.39 (32.2 %) vs Heat Pump (Intelligent Flux), or £0.63 after offsetting £1.76 gas stand. charge (6 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [52 Days | 5 Apr 26 to 26 May 26] Today 11.61 kWh; import saved £3.11 + export earned £0.57 Rates 26.8p import; 12.0p export Total 422.29 kWh; £100.52 total return (£1.93/day) Payback £689.90 left; 12.7% recovered; break-even 24 Jun 2027

Cost, Energy and Comfort Comparison [5 Days | 21 May 26 to 25 May 26] Boiler (Fixed) was cheaper by £1.71 (27.7 %) vs Heat Pump (Intelligent Flux), or £0.24 after offsetting £1.47 gas stand. charge (5 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [51 Days | 5 Apr 26 to 25 May 26] Today 11.12 kWh; import saved £2.92 + export earned £0.29 Rates 26.2p import; 12.0p export Total 410.69 kWh; £96.84 total return (£1.90/day) Payback £693.58 left; 12.3% recovered; break-even 28 Jun 2027

Cost, Energy and Comfort Comparison [4 Days | 21 May 26 to 24 May 26] Boiler (Fixed) was cheaper by £0.11 (3.2 %) vs Heat Pump (Agile), or £-1.06 after offsetting £1.17 gas stand. charge (4 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [50 Days | 5 Apr 26 to 24 May 26] Today 12.29 kWh; import saved £3.24 + export earned £0.38 Rates 26.4p import; 12.0p export Total 399.56 kWh; £93.64 total return (£1.87/day) Payback £696.78 left; 11.8% recovered; break-even 16 Jun 2027

Cost, Energy and Comfort Comparison [3 Days | 21 May 26 to 23 May 26] Boiler (Fixed) was cheaper by £0.42 (14.8 %) vs Heat Pump (Agile), or £-0.46 after offsetting £0.88 gas stand. charge (3 d × £0.293)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [49 Days | 5 Apr 26 to 23 May 26] Today 10.69 kWh; import saved £2.74 + export earned £0.30 Rates 25.6p import; 12.0p export Total 387.27 kWh; £90.02 total return (£1.84/day) Payback £700.40 left; 11.4% recovered; break-even 19 Jun 2027

Cost, Energy and Comfort Comparison [759 Days | 24 Apr 24 to 22 May 26] Actual: boiler £1510.51 vs Agile HP £2141.49 (£630.98 cheaper). Solar DHW: 170.5kWh tank heat ≈247.2kWh modeled gas input (1.45x). No-solar boiler ≈£1524.9; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [48 Days | 5 Apr 26 to 22 May 26] Today 11.07 kWh; import saved £2.89 + export earned £0.51 Rates 26.1p import; 12.0p export Total 376.58 kWh; £86.98 total return (£1.81/day) Payback £703.44 left; 11.0% recovered; break-even 20 Jun 2027

Boiler property vs HP ID 213 Detached: both Floor area: Boiler 165 m² HP 157 m² Heat loss: Boiler 4.20 kW HP 5.11 kW

Cost, Energy and Comfort Comparison [365 Days | 22 May 25 to 21 May 26] Actual: boiler £651.67 vs Agile HP £971.92 (£320.25 cheaper). Solar DHW: 170.5kWh tank heat ≈247.2kWh modeled gas input (1.45x). No-solar boiler ≈£666.1; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Cost, Energy and Comfort Comparison [180 Days | 22 Nov 25 to 20 May 26] Actual: boiler £475.63 vs Agile HP £678.61 (£202.98 cheaper). Solar DHW: 170.5kWh tank heat ≈247.2kWh modeled gas input (1.45x). No-solar boiler ≈£490.0; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [46 Days | 5 Apr 26 to 20 May 26] Today 3.75 kWh; import saved £0.96 + export earned £0.11 Rates 25.5p import; 12.0p export Total 358.13 kWh; £81.24 total return (£1.77/day) Payback £709.18 left; 10.3% recovered; break-even 27 Jun 2027

Cost, Energy and Comfort Comparison [90 Days | 19 Feb 26 to 19 May 26] Boiler (Tracker) was cheaper by £99.91 (37.9 %) vs Heat Pump (Agile), or £73.06 after offsetting £26.84 gas stand. charge (90 d × £0.298)🥇🎉 Prices based on @octopus.energy tariffs 💚

Solar payback: [45 Days | 5 Apr 26 to 19 May 26] Today 4.92 kWh; import saved £1.23 + export earned £0.12 Rates 25.0p import; 12.0p export Total 354.39 kWh; £80.17 total return (£1.78/day) Payback £710.25 left; 10.1% recovered; break-even 25 Jun 2027

Cost, Energy and Comfort Comparison [30 Days | 19 Apr 26 to 18 May 26] Actual: boiler £19.17 vs Agile HP £51.27 (£32.10 cheaper). Solar DHW: 109.4kWh tank heat ≈158.6kWh modeled gas input (1.45x). No-solar boiler ≈£28.3; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Safe DIY solar: panel + inverter share: DIY: £132/panel = 1.0x Company cash: £605/panel = 4.6x Company finance: £769/panel = 5.8x DIY can save a lot, but only when done properly, be brave and stay safe.

Solar payback: [44 Days | 5 Apr 26 to 18 May 26] Today 10.02 kWh; import saved £2.87 + export earned £0.52 Rates 28.6p import; 12.0p export Total 349.47 kWh; £78.83 total return (£1.79/day) Payback £711.59 left; 10.0% recovered; break-even 23 Jun 2027

Cost, Energy and Comfort Comparison [20 Days | 28 Apr 26 to 17 May 26] Actual: boiler £14.87 vs Agile HP £34.48 (£19.61 cheaper). Solar DHW: 47.2kWh tank heat ≈68.5kWh modeled gas input (1.45x). No-solar boiler ≈£18.9; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [43 Days | 5 Apr 26 to 17 May 26] Today 6.79 kWh; import saved £1.78 + export earned £0.12 Rates 26.2p import; 12.0p export Total 339.45 kWh; £75.44 total return (£1.75/day) Payback £714.98 left; 9.5% recovered; break-even 30 Jun 2027

Cost, Energy and Comfort Comparison [20 Days | 27 Apr 26 to 16 May 26] Actual: boiler £13.44 vs Agile HP £34.73 (£21.29 cheaper). Solar DHW: 55.3kWh tank heat ≈80.2kWh modeled gas input (1.45x). No-solar boiler ≈£18.1; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [42 Days | 5 Apr 26 to 16 May 26] Today 3.90 kWh; import saved £1.06 + export earned £0.02 Rates 27.2p import; 12.0p export Total 332.66 kWh; £73.53 total return (£1.75/day) Payback £716.89 left; 9.3% recovered; break-even 29 Jun 2027

Upon close data inspection, I’ve updated my solar DHW + boiler comparison model. Looking at energy input vs tank temperature rise: Immersion: 0.203 kWh/°C Gas boiler: 0.333 kWh/°C

Cost, Energy and Comfort Comparison [19 Days | 27 Apr 26 to 15 May 26] Actual: boiler £12.07 vs Agile HP £32.61 (£20.54 cheaper). Solar DHW: 55.3kWh tank heat ≈95.6kWh gas equiv (1.7x). No-solar boiler ≈£17.7; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

Solar payback: [41 Days | 5 Apr 26 to 15 May 26] Today 9.52 kWh; import saved £2.40 + export earned £0.35 Rates 25.2p import; 12.0p export Total 328.76 kWh; £72.45 total return (£1.77/day) Payback £717.97 left; 9.2% recovered; break-even 26 Jun 2027

Cost, Energy and Comfort Comparison [18 Days | 27 Apr 26 to 14 May 26] Actual: boiler £11.78 vs Agile HP £30.34 (£18.56 cheaper). Solar DHW: 55.3kWh tank heat ≈95.6kWh gas equiv (1.7x). No-solar boiler ≈£17.4; boiler still cheaper. Prices based on @octopus.energy tariffs 💚

1 April: Nice, electricity is about 4p/kWh cheaper. 14 May: Tariff renews and politely takes it all back. Turns out it was just a very slow April Fool’s joke. Joke’s on them though, every price rise just makes the solar payback posts more excited 🙃💚

Solar payback: [40 Days | 5 Apr 26 to 14 May 26] Today 8.22 kWh; import saved £2.17 + export earned £0.36 Rates 26.3p import; 12.0p export Total 319.24 kWh; £69.70 total return (£1.74/day) Payback £720.72 left; 8.8% recovered; break-even 29 Jun 2027

Cost, Energy and Comfort Comparison [17 Days | 27 Apr 26 to 13 May 26] Actual: boiler £10.58 vs Agile HP £28.04 (£17.46 cheaper). Solar DHW: 55.3kWh tank heat ≈95.6kWh gas equiv (1.7x). No-solar boiler ≈£16.2; boiler still cheaper. Prices based on @octopus.energy tariffs 💚