Monocrystalline vs Polycrystalline Solar Panels 2026 (UK)

Monocrystalline vs polycrystalline at a glance

Monocrystalline panels are made from a single silicon crystal, giving higher efficiency (typically 19–22%), a sleek all-black look and better performance in low light or smaller roofs. Polycrystalline panels are made from multiple silicon fragments, are cheaper to produce, but have lower efficiency (around 15–17%) and a blue, speckled appearance.

Cost and value

Polycrystalline panels usually cost less per panel, but because monocrystalline generates more electricity per square metre, the cost-per-kWh over the system's life is often comparable. On a typical UK roof in 2026, monocrystalline tends to deliver the best long-term value unless roof space is plentiful and budget is tight.

Which should you choose?

Choose monocrystalline if your roof is small, partly shaded, or you want the best efficiency and appearance. Choose polycrystalline if you have a large, unshaded roof and want to minimise upfront cost. Either way, a quality MCS-certified installation and inverter matter as much as the panel type.

How to choose step by step

1. Measure your roof space

Smaller or shaded roofs favour higher-efficiency monocrystalline panels.

2. Set your budget

Polycrystalline costs less upfront; monocrystalline generates more per square metre.

3. Compare efficiency and looks

Mono is ~19–22% and all-black; poly is ~15–17% with a blue tint.

4. Get three quotes

Compare at least three vetted MCS-certified installers for both types.

FAQs

Related guides

• Cost guides
• How to get an EV charger grant
• More comparisons