Are Solar Panels Worth It in South Wales?

Published by C&T Smart Energy · March 2026

It's the question we get asked most. And the honest answer is: yes — if it's designed and installed properly. Here's what the numbers actually look like for a typical South Wales home.

What Does South Wales Sunshine Actually Deliver?

South Wales gets an average of 1,500–1,600 peak sun hours per year. That's less than Spain, but more than enough. A well-positioned 4kW solar system in Swansea, Neath, or Carmarthenshire will typically generate 3,200–3,600 kWh of electricity annually — enough to cover 60–80% of an average household's electricity use.

The Real Savings Breakdown

With electricity at around 24p/kWh (2025 rates), a 4kW system generating 3,400 kWh per year represents £816 of potential savings — if you use all the energy you generate. In practice, without a battery, you'll self-consume around 30–40% of what you produce. That's still £245–£326 per year in direct savings, plus export payments for what you send back to the grid.

Why Battery Storage Changes the Equation

Most households use the bulk of their electricity in the morning and evening — not during peak solar generation hours. Without a battery, surplus energy is exported to the grid at 4–5p/kWh, while you buy it back later at 24p/kWh. That's a significant loss.

Add a 5–10kWh battery and your self-consumption jumps to 70–90%. Instead of exporting cheap, you store it and use it when you need it. This typically doubles your annual savings compared to solar alone.

What Makes a Good Solar Installation?

Not all solar installations are equal. The difference between a well-designed system and a poorly designed one can be thousands of pounds over the system's lifetime. Here's what matters:

• Full shading analysis — even partial shading can cut output by 30%+
• Panel orientation and tilt optimised for your specific roof
• Correctly sized inverter matched to your panel array
• Professionally accredited installation for warranty and export tariff eligibility
• Monitoring system so you can track performance over time

Property Value Impact

Beyond energy savings, solar PV consistently improves EPC ratings — often moving a property from band D to band C or higher. This directly impacts property value and mortgage eligibility, with research suggesting solar adds 4–14% to a home's value in the UK.