- Panel and battery prices have fallen ~40% since 2021 in real terms
- 0% VAT on solar and battery storage until 31 March 2027
- Smart Export Guarantee tariffs continue to pay 4–15p/kWh for exported electricity
Net effect: payback periods for a typical Lancashire solar + battery install are now 9–12 years, versus 15–18 years in 2018. After payback, the system continues generating for 15+ years effectively free.
The honest 5-scenario answer
Whether solar is worth it for your specific Lancashire home depends on which of these five scenarios you fit. We’ve modelled each one using Thermova’s 2026 quote data and real Fylde Coast generation.
Scenario 1: South-facing roof, family home, gas heating → clear YES
| Property | 3–4 bed semi or detached, south-facing main roof, gas combi heating |
|---|---|
| Household | Family of 3–5, 4,500–6,500 kWh/year electricity use |
| System | 5–6 kWp solar + 10 kWh battery |
| All-in install (0% VAT) | £13,500 – £17,000 |
| Year-one bill saving + SEG | £1,200 – £1,500 |
| Simple payback | ~10 years |
| 20-year net benefit | £25,000+ |
If your roof and household look anything like this, solar is decisively worth it. The Cleveleys case study on our blog is a real example in this bracket.
Scenario 2: East/West-facing roof, EV household, heat-pump tariff → strong YES
| Property | Split-pitch roof (no south face), EV charged at home |
|---|---|
| Household | 4,000–8,000 kWh/year (EV included) |
| System | 5–6 kWp solar (split E/W) + 10 kWh battery |
| Generation vs south-facing | 85–90% |
| Tariff | Octopus Intelligent or Cosy (time-of-use) |
| Simple payback | ~10.5 years (longer than south-facing but still in the strong-return bracket) |
East/west doesn’t cost the system economics nearly as much as people assume — and split E/W generation spreads through the day, often improving self-consumption.
Scenario 3: Combined with a heat pump → very strong YES
If you’re installing (or already have) an air source heat pump, solar dramatically improves the heat pump’s running cost by powering it during daylight hours, particularly in shoulder seasons (April–June, September–October). Combined systems consistently deliver 8–10 year combined payback in Lancashire, with the highest carbon savings of any home upgrade. See the Whole-Home Renewable Case Study for a real Garstang example.
Scenario 4: Selling within 4 years → MARGINAL
Solar doesn’t recover its install cost in 4 years — payback is 9–12 years. But over 4 years you still bank the bill savings, roughly £4,800 to £6,000 on a typical install, and you may get a resale uplift on top. How much is genuinely uncertain. The strongest evidence for a large premium, the Swansea and Birmingham study finding 6.1 to 7.1%, rests on Feed in Tariff era data, so it likely overstates what a system bought today adds. Treat any sale uplift as a bonus, not the reason to buy. Honest answer: on a 4-year-sale horizon solar is marginal. Install it for the bill savings you would enjoy now, not as a sale-uplift play.
Scenario 5: Very small system, no battery, peak-only usage → MARGINAL or NO
| Property | Small terrace, 1–2 occupants, mostly out at work |
|---|---|
| Annual electricity use | <2,500 kWh |
| System | 3 kWp solar, no battery |
| Self-consumption | ~25% (most generation exported) |
| Simple payback | ~14–16 years |
For very small households with no daytime usage and no battery, most generation gets exported at low SEG rates (4–8p/kWh) rather than offsetting expensive grid imports (28p/kWh). Payback stretches to 14–16 years. Adding a battery transforms the maths (back to 10–12 years), but the upfront cost may not justify the small annual saving.
When solar isn’t worth it (the honest answer Thermova will give you)
Thermova has walked away from quotes where the customer wanted solar but the property didn’t fit. The honest checklist:
- North-facing roof with no alternative pitch. Generation drops to 50–60% of south-facing equivalent — payback stretches to 15+ years.
- Heavy shading from chimneys, mature trees, or tall neighbouring buildings for >40% of daylight hours. Optimisers (SolarEdge/Enphase) can recover some performance but the economics often don’t justify the install.
- Roof in poor structural condition with replacement needed in <10 years. Better to retrofit the roof first, install solar after.
- Planning to move in <3 years and unwilling to absorb the upfront cost as a quality-of-living investment rather than a financial one.
- No battery and no daytime electricity usage. Pure-export installs at 2026 SEG rates rarely justify themselves.
- Properties in conservation areas / listed buildings where panel design is heavily restricted. Possible but with significant cost premium for in-roof integrated panels.
If your property hits two or more of these, Thermova will tell you straight that solar isn’t the right next move — and suggest alternatives (insulation top-up, heat pump if eligible, EV charger, smart-tariff optimisation).
The trust-building bit: how to pressure-test any solar quote
Whether you’re comparing Thermova against another installer or just trying to filter the noise online, four questions will tell you whether the quote is honest:
| 1. “What generation per kWp are you assuming, and where does that figure come from?” | Honest installers cite PVGIS data + their own metered installs and quote 830–890 kWh/kWp for Lancashire. Optimistic ones quote 950+ kWh/kWp (often by basing it on Midlands or South-coast data). |
|---|---|
| 2. “What battery self-consumption rate are you assuming?” | Honest figures sit at 65–80%. Anyone quoting 90%+ is either modelling unusual usage patterns or being optimistic. |
| 3. “What’s the year-one bill saving in real pounds, given my actual electricity use, my actual tariff, and the SEG rate I’ll be on?” | Vague “£X up to £Y” savings are a red flag. A real installer can model your actual bill. |
| 4. “What happens if I sell the house in 5 years — is the system transferable?” | All MCS-certified installs transfer to the new owner with the paperwork; warranties remain valid. If an installer is vague on this, ask why. |