⚡ Battery Load-Shifting Strategy
Compare costs across tariffs with smart battery charging strategies for each season
You can switch tariffs as often as you like! Here's what you'd save by using different tariffs for different seasons:
📅 Recommended Switching Schedule
| Season | Months | Best Single | Cosy→Flux | Cosy→iFlux | Go→Flux | Go→iFlux | Optimal |
|---|---|---|---|---|---|---|---|
| ❄️ Winter | Nov - Feb |
Cosy
£682 |
Cosy
£682 |
Cosy
£682 |
Go
£922 |
Go
£922 |
Cosy
£682 |
| 🌸 Spring | Mar - Apr |
Cosy
£140 |
Cosy
£140 |
Cosy
£140 |
Go
£191 |
Go
£191 |
Cosy
£140 |
| ☀️ Summer | May - Aug |
iFlux
£-348 |
Flux
£-319 |
iFlux
£-348 |
Flux
£-319 |
iFlux
£-348 |
iFlux
£-348 |
| 🍂 Autumn | Sep - Oct |
Cosy
£156 |
Cosy
£156 |
Cosy
£156 |
Go
£189 |
Go
£189 |
Cosy
£156 |
| Annual Total | £1,056 | £659 | £630 | £983 | £954 | £630 | |
⚡ Flux vs Intelligent Flux - Key Differences
• Export: 9.98p / 28.73p peak
• Best for: Peak export arbitrage
• Export: 23.79p / 31.72p peak
• Best for: All-day export, simpler rates
📅 Seasonal Breakdown
Minimal solar - charge from grid overnight • Avg solar: 2.5 kWh/day
| Tariff | Charge Source | Charge Cost | Peak Savings | Battery Benefit | Energy Cost | Export | Daily Total | Season Total |
|---|---|---|---|---|---|---|---|---|
|
Octopus Cosy
BEST |
☀️ 1.0 kWh
⚡ 17.7 kWh |
-£2.53 | +£3.51 | +£0.97 | £6.05 | - | £5.69 | £682 |
| Octopus Go |
☀️ 1.0 kWh
⚡ 17.7 kWh |
-£1.50 | +£2.49 | +£0.99 | £8.05 | - | £7.68 | £922 |
| Octopus Flux |
☀️ 1.0 kWh
⚡ 17.7 kWh |
-£2.99 | +£2.26 | £-0.73 | £7.76 | - | £9.11 | £1,093 |
| Intelligent Flux |
☀️ 1.0 kWh
⚡ 17.7 kWh |
-£4.20 | +£2.54 | £-1.67 | £7.02 | - | £9.30 | £1,116 |
Mixed strategy - solar + grid top-up • Avg solar: 12 kWh/day
| Tariff | Charge Source | Charge Cost | Peak Savings | Battery Benefit | Energy Cost | Export | Daily Total | Season Total |
|---|---|---|---|---|---|---|---|---|
|
Octopus Cosy
BEST |
☀️ 8.0 kWh
⚡ 9.9 kWh |
-£1.42 | +£2.63 | +£1.21 | £2.89 | - | £2.29 | £140 |
| Octopus Go |
☀️ 8.0 kWh
⚡ 9.9 kWh |
-£0.84 | +£1.87 | +£1.03 | £3.54 | - | £3.13 | £191 |
| Octopus Flux |
☀️ 8.0 kWh
⚡ 9.9 kWh |
-£1.67 | +£1.69 | +£0.02 | £3.67 | - | £4.27 | £260 |
| Intelligent Flux |
☀️ 8.0 kWh
⚡ 9.9 kWh |
-£2.35 | +£1.90 | £-0.45 | £3.57 | - | £4.63 | £283 |
No heat pump - export battery at peak rates! • Avg solar: 22 kWh/day
| Tariff | Charge Source | Charge Cost | Peak Savings | Battery Benefit | Energy Cost | Export | Daily Total | Season Total |
|---|---|---|---|---|---|---|---|---|
|
Intelligent Flux
BEST |
☀️ 16.9 kWh | £0.00 | +£4.82 | +£4.82 | £1.40 | +£0.02 | £-2.83 | £-348 |
| Octopus Flux | ☀️ 16.9 kWh | £0.00 | +£4.64 | +£4.64 | £1.44 | +£0.01 | £-2.59 | £-319 |
| Octopus Cosy | ☀️ 16.9 kWh | £0.00 | +£1.10 | +£1.10 | £1.14 | +£0.02 | £0.63 | £78 |
| Octopus Go | ☀️ 16.9 kWh | £0.00 | +£0.78 | +£0.78 | £1.38 | +£0.02 | £1.21 | £149 |
Mixed strategy - solar + grid top-up • Avg solar: 8 kWh/day
| Tariff | Charge Source | Charge Cost | Peak Savings | Battery Benefit | Energy Cost | Export | Daily Total | Season Total |
|---|---|---|---|---|---|---|---|---|
|
Octopus Cosy
BEST |
☀️ 5.0 kWh
⚡ 13.2 kWh |
-£1.89 | +£2.63 | +£0.74 | £2.68 | - | £2.55 | £156 |
| Octopus Go |
☀️ 5.0 kWh
⚡ 13.2 kWh |
-£1.12 | +£1.87 | +£0.74 | £3.23 | - | £3.10 | £189 |
| Octopus Flux |
☀️ 5.0 kWh
⚡ 13.2 kWh |
-£2.24 | +£1.69 | £-0.55 | £3.39 | - | £4.55 | £277 |
| Intelligent Flux |
☀️ 5.0 kWh
⚡ 13.2 kWh |
-£3.15 | +£1.90 | £-1.24 | £3.33 | - | £5.19 | £317 |
With no heat pump running in summer, your peak usage drops to ~2.5 kWh. This unlocks a powerful arbitrage opportunity on Flux!
📊 Daily Summer Calculation (Flux)
| Battery capacity (usable) | 16.9 kWh |
| After efficiency (90%) | 15.2 kWh |
| Keep for self-use (peak) | -2.5 kWh |
| Available to export | 12.7 kWh |
| Export earnings (@ 28.73p) | +£3.65 |
| Self-consumption savings | +£0.99 |
| Daily battery benefit | £4.64 |
🔋 Cosy Strategy
- Charge battery during 22:00-00:00 window (14.33p)
- Top up during 04:00-07:00 if needed
- Discharge during peak 16:00-19:00 (saves 43.83p)
- Best spread: 29.5p/kWh savings per cycle
🔋 Go Strategy
- Charge battery 00:30-05:30 (8.50p)
- 5 hours = plenty for full charge
- Use throughout day (saves 31.14p)
- Best spread: 22.64p/kWh savings per cycle
🔋 Flux Strategy
- Winter: Charge 02:00-05:00 (16.93p), self-consume
- Summer: Charge from solar (FREE)
- Summer: Export battery at peak 28.73p!
- Summer bonus: ~£5/day from export
☀️ Summer Strategy (May-Aug) - No Heat Pump
With the heat pump off, your daily usage drops to ~12 kWh and peak usage to just ~2.5 kWh. On Flux, this means you can export most of your solar-charged battery at 28.73p/kWh during peak hours, only buying back the small amount you need. This generates ~£600+ over 4 months just from battery arbitrage!
❄️ Winter Strategy (Nov-Feb) - Heat Pump Running
With minimal solar and high heat pump usage (~40 kWh/day), battery self-consumption is key. Octopus Go offers the cheapest overnight charging at 8.50p/kWh. Cosy's multiple cheap windows (8 hours vs 5) give more flexibility for heat pump scheduling. In winter, self-consumption beats export as you need all the stored energy.
🍂🌸 Shoulder Seasons (Mar-Apr, Sep-Oct)
Mixed strategy works best. Use solar to partially charge battery, top up from grid at cheap rates if needed. Heat pump usage varies with weather - monitor and adjust. On good solar days, consider Flux export strategy.