Why is summer output so much higher?

Three reasons: (1) More daylight hours (16hrs in June vs 8hrs in December). (2) Higher sun angle = more direct light. (3) Less cloud cover on average. June produces 5-6x more than December.

Does location in the UK matter?

Yes — southern England gets ~10% more solar than Scotland. The figures above are for southern England. Subtract 5-10% for Midlands, 10-15% for northern England, 15-20% for Scotland.

How much of this can I actually use?

Without battery: 30-50% (self-consumption). With battery: 70-85%. The rest is exported for SEG payments. Self-consumed electricity saves 26.32p/kWh; exported earns 4-15p/kWh.

Can I cover my bills entirely in summer?

Usually yes — a 4kW system generates 450-580 kWh/month in summer. Average monthly use: 240 kWh. You'll export 200-340 kWh surplus. Your summer electricity bill should be near zero or negative.

Solar Output Per Month UK

By Home Solar Guide Team|Updated 20 October 2026|educational

Independently written | Plain-English guide

Solar output per month — A 4kW system: 80kWh in December to 550kWh in June. Monthly average: 290-350kWh.

What would this actually cost at your home?

Installed prices vary widely by roof, access and region. Get an installed price for your property from MCS-certified installers.

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What would this actually cost at your home?

Installed prices vary widely by roof, access and region. Get an installed price for your property from MCS-certified installers.

Get an Installed Price

How much electricity do solar panels generate per month?

Monthly electricity generation from a 4kW solar panel system in southern England: JANUARY: 90-120 kWh. FEBRUARY: 130-170 kWh. MARCH: 240-300 kWh. APRIL: 350-420 kWh. MAY: 450-530 kWh. JUNE: 480-580 kWh. JULY: 470-560 kWh. AUGUST: 400-480 kWh. SEPTEMBER: 300-360 kWh. OCTOBER: 190-240 kWh. NOVEMBER: 100-140 kWh. DECEMBER: 70-100 kWh. ANNUAL TOTAL: 3,500-4,200 kWh. Average UK household uses 2,900 kWh/yr — so a 4kW system generates 120-145% of total annual consumption. In summer: you generate far more than you use. In winter: you generate less and rely more on the grid. A battery evens this out.