Solar + Battery Savings: Real Numbers

Published by C&T Smart Energy · March 2026

Everyone asks the same question: “How much will I actually save?” Let’s stop guessing and start calculating. Here’s what real South Wales homeowners are seeing.

The Setup: A Typical South Wales Home

• 3-bedroom semi in Swansea
• Annual electricity bill: £1,200
• Average use: 3,500 kWh/year
• 4kW solar + 5kWh battery

Year 1 Savings Breakdown

A 4kW system generates about 4,800 kWh/year in South Wales.

• Without battery: covers 60% of usage, annual savings: ~£720
• With 5kWh battery: covers 75% of usage, annual savings: ~£840

Battery Advantage: +£120/year. Over 10 years, that’s £1,200+ extra savings.

Long-Term Projections

• 10-year total savings: £9,450
• 25-year total savings: £28,500
• System cost (installed): £11,500
• Net return: £17,000
• Payback period: 13–14 years

Maintenance is minimal — budget £0–£50/year for cleaning and monitoring. Inverter replacement (~year 10–12) is the only major cost.

Real Customer Examples

• Swansea Family: 5kW solar + 5kWh battery, Year 1 savings: £1,050, 10-year: £11,200
• Neath Couple: 4kW solar + 5kWh battery, Year 1: £840, 10-year: £9,450
• Bridgend Landlord: 3.5kW solar, Year 1: £520, 10-year: £5,800, EPC improvement

How to Get Your Personalised Numbers

Every home is different. Your savings depend on your current bill, roof orientation, shading, and usage patterns. That’s why we offer a free, no-obligation solar assessment:

1. Survey your roof and bills
2. Model your savings (solar only vs. solar + battery)
3. Show payback timeline and ROI
4. Explain finance and grant options