A solar carport is a significant investment. Understanding the financial return is crucial before committing. This guide walks through realistic savings calculations for the UK and explains where genuine value comes from.
Solar Generation Across the UK
A typical 6kWp solar carport generates approximately 4,500-5,500 kWh annually depending on location. In East Anglia, typical generation is 5,000-5,500 kWh annually. This assumes:
- South-facing orientation (ideal for UK)
- Minimal shading
- Professional installation with optimised panel angles
- Average weather patterns (accounting for cloudy winter months)
For perspective, average UK household consumption is 2,700 kWh annually. A 6kWp carport generates roughly 1.8-2x household demand—excess energy you store or export.
Energy Consumption Breakdown
Your actual savings depend on consumption patterns. A typical household:
- Daytime consumption (7am-4pm): ~30-35% of annual use
- Evening/peak (4pm-11pm): ~40-45% of annual use
- Night consumption: ~20-25% of annual use
Without battery storage, you capture 30-35% of carport generation directly (daytime self-consumption). Without battery storage, the remaining 65-70% is exported to the grid at lower rates (~15p/kWh Smart Export Guarantee) rather than the rate you'd pay to import (~35p/kWh).
Annual Savings Without Battery (Year 1)
Conservative scenario: 6kWp carport, no battery storage:
| Component | Calculation | Annual Saving |
|---|---|---|
| Direct self-consumption (30%) | 1,650 kWh @ £0.35/unit | £578 |
| Exported energy (70%) | 3,850 kWh @ £0.15/unit | £577 |
| Total Year 1 (no battery) | £1,155 |
Annual Savings With Battery Storage
Add a 10kWh battery system, everything changes:
| Component | Calculation | Annual Saving |
|---|---|---|
| Direct self-consumption | 1,650 kWh @ £0.35/unit | £578 |
| Battery-assisted evening use | 2,500 kWh @ £0.35/unit | £875 |
| Remaining export (overflow) | 1,350 kWh @ £0.15/unit | £202 |
| Total Year 1 (with 10kWh battery) | £1,655 |
Battery impact: A 10kWh battery adds £500/year in savings by storing solar generation for evening use instead of exporting at lower rates. This alone justifies the battery cost over 8-10 years.
EV Charging Impact
Add a MyEnergi Zappi EV charger with solar-priority mode, and the equation improves further:
Typical EV: 50-60 kWh battery, charges 3-4 times weekly. Smart charging prioritises solar generation:
- Charging 20 kWh weekly from solar (vs grid): 1,040 kWh annually
- At £0.35/kWh grid rate vs £0.04/kWh solar equivalent: £32.32/week saving
- Annual EV charging saving: ~£1,680
For households with EVs, solar carport savings are substantially higher. This is particularly compelling because petrol/diesel costs continue rising; your solar-charged miles become increasingly cost-advantaged.
Realistic Total Year 1 Savings (Typical Scenario)
6kWp carport + 10kWh battery + EV charging:
- Household energy self-consumption: £578
- Battery-assisted evening use: £875
- Remaining export: £202
- EV charging savings: £1,680
- Total Year 1: £3,335
Payback Period Calculation
Assume a £48,000 installed cost (carport, solar, battery, installation):
- Estimated payback period: 14-16 years
- Post-payback period: 10+ years of cost-free energy (panel warranty typically 25 years)
- 20-year total savings: £45,000-£55,000 (accounting for inflation and rate increases)
Without battery and EV, payback extends to 18-22 years. With battery alone (no EV), payback is 12-14 years.
Depreciation and Long-Term Value
The financial case improves significantly when property value is included:
- An installed solar carport with battery adds £15,000-£25,000 to property value (conservative estimate)
- A bespoke oak-framed carport with integrated solar adds more (architectural quality commands premium)
- When property value increase is factored in, payback period shortens to 10-12 years
Sensitivity Analysis
Savings vary by consumption pattern and energy prices. Key variables:
- Rising energy prices: If UK electricity rates rise to £0.50/kWh (tracking recent trends), annual savings increase 40-50%
- Higher consumption: Families with higher demand (heat pump, multiple EVs) see 30-50% higher savings
- South-facing orientation: East/west-facing carports generate 10-15% less; savings proportionally lower
- Shading: If 20% of panels are shaded, generation drops similarly
Comparing Alternatives
Why a carport over roof-mounted panels?
- Space efficiency: You generate energy where you park, not occupying roof space
- Practical benefit: Carport provides vehicle protection—dual-purpose infrastructure
- Aesthetic appeal: Oak-framed carport adds property value through design, not just energy generation
- Future-proofing: Easier to add battery, EV charger, or additional panels later to a carport
Common Misconceptions
"I'll recoup it in 5 years." Not realistic without substantial EV charging or unusually high consumption. 12-16 years is typical.
"Panels only work in summer." Winter generation is 20-30% of summer—significant enough that year-round self-consumption is worthwhile.
"Battery pays for itself in energy savings alone." Battery ROI is 8-10 years on energy alone; property value appreciation accelerates this.
The Strategic Case Beyond ROI
Pure financial ROI doesn't capture everything:
- Energy independence: Reducing grid dependence provides security against price rises and supply disruption
- Environmental alignment: Aligns your home with net-zero commitments and carbon reduction
- Resilience: Battery storage provides backup power during grid outages
- Lifestyle upgrade: EV charging and solar integration improves daily convenience
Next Steps
Every property differs. Your actual savings depend on consumption, orientation, shading, and future energy prices. We provide detailed personalised projections during consultations—based on your specific circumstances, not generic estimates.
Financial incentives and grants (such as OZEV for EV chargers) can also improve overall ROI. These vary by region and change periodically.