How Energy Performance Certificates Handle Solar PV and Battery Storage

As more UK homes adopt solar photovoltaic (PV) systems and battery storage, homeowners and landlords are rightly asking:
“How do these upgrades impact my EPC rating?”

While solar tech is a major step toward greener living, the way it’s treated in Energy Performance Certificates (EPCs) isn’t always straightforward. Let’s explore exactly how solar PV and batteries are assessed, what influence they have on your score, and how to maximise their EPC impact.

☀️ Does Solar PV Improve an EPC Rating?

Yes—but not always dramatically. Solar panels reduce the carbon intensity of electricity used in your home, and this improvement is recognised in EPC assessments.

Here’s how it works:

• The EPC system uses SAP (Standard Assessment Procedure) or RdSAP to estimate your energy usage and CO₂ emissions.

• Solar PV reduces your electricity demand from the grid, thereby lowering CO₂ emissions.

• As a result, it improves your Environmental Impact (CO₂) rating and sometimes your overall EPC band.

📉 The benefit varies depending on your existing setup. Homes with electric heating may see bigger gains than those with efficient gas boilers.

🔋 What About Battery Storage?

Battery systems allow you to store excess solar power and use it when needed, often at night. This seems like a huge benefit—but here’s the catch:

⚠️ Battery storage is not currently accounted for in SAP/RdSAP calculations.

This means:

• No direct EPC rating improvement is awarded for installing a battery.

• The system assumes solar energy is only used when generated—not stored.

✅ However, you’ll still get the solar PV credit, and battery storage may help with future-proofing, energy independence, and real savings—just not an EPC boost (yet).

🔍 What EPC Assessors Actually Look For

When conducting an EPC, assessors will:

If no documentation is available, default values are used—so always have installation paperwork ready.

🧾 How to Maximise the EPC Impact of Solar PV

Want your solar setup to truly count in your EPC?

Here’s what to do:

1. Provide an MCS certificate or installer report showing:

   • Total installed capacity (e.g. 3.6 kWp)

   • Date of installation

   • Orientation and tilt

2. Make sure the system is visibly installed and accessible to the assessor.

3. Pair it with electric heating or hot water systems (solar boosts EPC more in all-electric homes).

4. Reduce demand elsewhere—loft insulation and lighting still weigh heavily in your EPC.

🏡 Example: Solar PV in Action

💡 As you can see, PV alone won’t always take you from Band E to B, but it can nudge your rating upward, especially when combined with other improvements.

🔮 What About Future EPC Updates?

The EPC system is being revised as part of the UK’s Net Zero strategy, and it’s expected that:

• Battery storage may be included in future SAP versions.

• Smart grid interaction and load shifting may also be rewarded.

• The system will better reflect real-world energy performance, not just theoretical models.

⚠️ Important: Solar Thermal ≠ Solar PV

Don’t confuse solar thermal (used for hot water) with solar PV (used for electricity). Both are included in EPC calculations—but:

• Solar thermal influences water heating energy use

• Solar PV influences electricity and carbon emissions

🛠 Need Help?

At EPCrate.co.uk, we:

• Understand how to properly document renewable systems

• Guide you on which upgrades will actually move your EPC band

• Work with landlords, agents, and homeowners across London and beyond

✅ Summary: What Counts, What Doesn’t

Thinking of installing solar PV or already have a system?
Book an EPC assessment with us to see your upgrade reflected in your rating.

👉 Book Now at EPCrate.co.uk