CO2 Calculator: Your Carbon Savings

How much CO₂ do solar panels save?

Solar panel CO₂ savings in relatable terms (using BEIS Greenhouse Gas Conversion Factors 2025, gov.uk): 4kW SYSTEM — 25-YEAR CARBON SAVINGS: Total: 17.1 tonnes CO₂ (net of manufacturing). Equivalent to: (1) 4.5 return flights London-New York. (2) Not driving a petrol car for 42,500 miles. (3) Planting 780 trees and letting them grow for 10 years. (4) Powering 5.8 UK homes for one year on renewable electricity. (5) Removing 3.7 petrol cars from the road for one year. (6) 37,000 smartphone charges. CALCULATION: Annual generation: 3,800 kWh × UK grid carbon factor (180g CO₂/kWh) = 684 kg CO₂/yr saved. 25 years: 17,100 kg. Minus manufacturing: ~2,000 kg. Net: ~15,100 kg = 15.1 tonnes minimum. Manufacturing carbon payback: 2.5-3 years. After that: every kWh is genuinely zero-carbon. BY SYSTEM SIZE: 3kW = 12.8 tonnes. 5kW = 21.4 tonnes. 6kW = 25.7 tonnes. 8kW = 34.2 tonnes. 10kW = 42.8 tonnes. Sources: BEIS GHG Conversion Factors (gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors), DEFRA emission equivalents, IEA PVPS lifecycle data.