How much electricity will solar panels generate in Scotland?

A 4kW solar panel system in Scotland typically generates between 3,200 and 3,800 kWh per year. Output varies by location, with east coast areas (Edinburgh, Aberdeen) generally achieving slightly higher yields than west coast regions.

What factors affect solar panel output?

Key factors include roof orientation (south-facing is optimal), roof pitch (30-40 degrees ideal), shading from trees or buildings, local weather patterns, and panel quality. Location within Scotland also affects output by 5-10%.

How do I calculate solar panel output for my home?

Multiply your system size in kW by the local yield factor (typically 800-950 kWh per kW in Scotland), then apply adjustments for orientation, pitch, and shading. A south-facing 4kW system might generate 4 x 900 = 3,600 kWh annually.

What is kWp and how does it relate to actual output?

kWp (kilowatt peak) is the rated power output under standard test conditions. Actual output is always lower than rated capacity due to real-world factors like temperature, angle, and weather. In Scotland, expect 800-950 kWh per kWp annually.

Solar Output Calculator

Published: 01/12/2026

Last Updated: 02/07/2026

This guidance is reviewed periodically to reflect evolving renewable energy practices and current Scottish regulations.

How much electricity will my solar panels generate in Scotland?

Your typical 4kW system generates 3,200-3,800 kWh annually in Scotland, or 800-950 kWh per kWp installed. East coast locations (Edinburgh, Aberdeen) achieve higher yields around 920 kWh per kWp, while west coast sees 850 kWh per kWp. Your actual output depends on roof orientation, pitch, shading, and local weather patterns.

Calculate Your Output

System Size (kW)

4 kW

Typical home: 3-5 kW

Location

Roof Orientation

Roof Pitch

Shading

Estimated Annual Output

3,520

kWh per year

Average monthly293 kWh

Summer peak (June)493 kWh

Winter low (December)106 kWh

Yield per kWp880 kWh/kWp

Monthly Generation Estimate

Jan

141

Feb

176

Mar

282

Apr

387

May

458

Jun

493

Jul

458

Aug

422

Sep

317

Oct

211

Nov

141

Dec

106

Understanding the Calculation

Base Yield by Location

Scotland's solar irradiance varies by region. East coast areas receive slightly more sunshine due to drier conditions, while west coast and highland areas have more cloud cover.

920

kWh/kWp East

880

kWh/kWp Central

850

kWh/kWp West

820

kWh/kWp Highlands

Orientation Impact

Roof orientation significantly affects output. South-facing roofs receive maximum sunlight, while east/west orientations lose approximately 15%. North-facing roofs are generally unsuitable.

South: 100%SE/SW: 95%E/W: 85%North: 55%

Shading Effects

Even partial shading can significantly reduce output. Modern panels and microinverters help mitigate effects, but avoiding shade remains important. Consider seasonal changes in shadow patterns.

None: 100%Light: 90%Moderate: 75%Heavy: 50%

Important Notes

This calculator provides estimates based on typical Scottish conditions. Actual output may vary by 10-15% depending on specific site conditions and weather patterns.
Panel degradation (typically 0.5% per year) is not included. Output will gradually decrease over the system lifetime.
For accurate estimates, request a professional site assessment from an MCS-certified installer.

Bottom Line on Solar Output in Scotland

Scottish solar systems generate 800-950 kWh per kWp annually, with east coast locations (Edinburgh, Aberdeen) achieving 920 kWh per kWp and west coast (Glasgow, Ayrshire) producing 850 kWh per kWp
A typical 4kW system generates 3,200-3,800 kWh annually in Scotland—enough to meet 80-95% of average household electricity consumption of 3,000-4,000 kWh
South-facing roofs achieve optimal output, but southeast/southwest orientations reach 95% performance and east/west deliver 85%—all viable options for Scottish installations
Roof pitch of 30-40 degrees is optimal for Scotland's latitude, but pitches between 15-50 degrees still achieve 95% of maximum output with minimal performance loss
Shading is the biggest output killer—light shading cuts 10%, moderate shading reduces 25%, and heavy shading slashes 50% of potential generation
Scotland produces 85-90% of southern England's solar output due to latitude and weather, but cooler temperatures improve panel efficiency by 5-10%, partially offsetting this difference