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Solar PV Generation & Savings

Estimate annual solar PV generation, bill savings and carbon saved from system size, yield and tariffs.

System Size

kWp

Σ of module STC ratings (MCS MIS 3002)

Reference Yield

kWh/kWp

Enter the PRE-loss yield — PR is applied below. Pasting a PVGIS/MCS specific (final) yield instead? Set PR to 1.0.

Performance Ratio

0–1

IEC 61724-1 system losses (temperature, soiling, inverter, wiring)

Self-consumption

0–1

Share used on-site; rest exported. UK no-battery ≈ 0.30

Import Tariff

£/kWh

Grid unit rate avoided (Ofgem cap Oct–Dec 2025 ≈ 0.2635)

Export Rate

£/kWh

Smart Export Guarantee — supplier-set; default illustrative

Grid Carbon Factor

kgCO₂e/kWh

DESNZ/Defra 2025 'electricity generated' ≈ 0.177

Enter the system size to estimate generation