Solar PV & Battery Storage: EPC points and cost

Do solar panels improve your EPC rating? Yes, but not cheaply

Yes, solar panels raise an EPC score. A typical ~4 kWp domestic system adds around +6 to +15 SAP points, with published guides ranging from +6 to +10 up to +10 to +15 depending on the property. The reason is straightforward: an EPC is a SAP rating from 1 to 100 that models the annual running cost of your home per square metre of floor area, and on-site generation offsets that modelled cost, so the score goes up.

The honest part, which most solar sales pages skip, is the cost per point. At £4,500 to £8,000 installed for +6 to +15 points, solar works out at roughly £400 to £800 per point. Set that against a £25 hot-water cylinder jacket, a £450 loft top-up at around £50 to £100 per point, or £60 of LED lamps at £10 to £40 per point, and solar is clearly a mid-table value measure, genuinely useful, but rarely the cheapest first point on any certificate.

So the answer to “will solar sort my rating out in one go?” is: it helps, sometimes a lot, but on its own it can be the expensive way up. The strong play, the one that actually earns its money on the EPC, is solar as the finisher: the measure you fit after the cheap fabric and controls points, where it is often exactly what lifts a solid band C into band B. Fit the cheap points first; fit solar to close the gap.

Where solar earns its place on the certificate

Solar is at its best on the EPC in two situations. First, when you are a handful of points short of a band threshold, band C starts at 69 and band B at 81, and the cheaper measures have run out, a well-sited array can be exactly the jump you need. Second, on a well-insulated home where the fabric points are already banked, generation is one of the few remaining levers. What solar does not do is substitute for insulation: it offsets running cost but it does not improve the fabric, which matters for the future rules (more below). For the full ranking of every measure by cost per point, see our cost per point breakdown.

What solar costs, and the cost per point verdict

For a typical domestic install:

• ~4 kWp system (around 10 panels): roughly £4,500 to £8,000, depending on roof complexity, scaffolding, inverter choice and whether battery storage is added.
• Battery storage: an additional cost, but now genuinely worth having recorded, see the RdSAP 10 section below.

The cost-per-point verdict is deliberately blunt: ~£400 to £800 per point makes solar a mid-table measure, not a value leader. It sits well below double glazing (documented at around £2,700 per point) but well above the quick wins and loft insulation. That places it firmly in the “finisher, not opener” category. If your only aim is to clear the 69-point band C threshold for the least money, the cheapest EPC improvements and insulation get you there far more cheaply. If you have already banked those and need the last points into B, solar is often the right call.

Owners weighing solar against the other low-carbon measure should also read our heat pump and EPC guide, the two are frequently considered together, and the sequencing logic (cheap fabric first, low-carbon generation and heating after) is the same for both.

Working the arithmetic: where solar fits in the sequence

The reason solar belongs late in the plan is best shown with the gap arithmetic that this whole site is built on. Improving an EPC is not guesswork, it is subtraction. Find your current score (the number, not the letter), subtract it from your target threshold (band C is 69, band B is 81), and that is the number of points you need to buy, in cost-per-point order.

Take a home currently sitting at 64 points, a mid-band-D property five points short of C. The cheapest points come first: LED lamps throughout at £20 to £80 for +1 to +3, a hot-water cylinder jacket at £15 to £80 for +1 to +4, full heating controls at £150 to £500 for +2 to +5, and draught-proofing at £30 to £250 for +1 to +3. That package alone routinely clears the five-point gap into C for well under £1,000. Spending £6,000 on solar to make the same jump would be paying £400 to £800 per point for something £10 to £150 per point could achieve, which is exactly why solar is the wrong opening move for a band-C goal.

Now take a home already on a solid 76, comfortably in band C but five points short of B at 81. Here the cheap measures are typically already banked, the fabric is decent, and the remaining levers are few. This is precisely the situation where a ~4 kWp array, adding +6 to +15 points, is often the measure that lifts the home over the 81-point line into band B. Same panels, same cost per point, but now it is buying points that nothing cheaper can, which is what makes solar a value measure in this position and a poor one earlier.

That is the honest logic in a sentence: solar’s cost per point never changes, but its usefulness does, depending entirely on whether cheaper points are still available. Work out your own gap first, our FAQs walk through the thresholds, and only reach for solar once the cheap points are spent.

Who solar is right for

• Homes near a band threshold. If you are sitting on 63 to 68 points and the cheap measures are exhausted, a ~4 kWp array can be the jump into C. If you are on a solid C in the mid-70s, solar is a strong candidate for the push into B.
• Well-insulated properties. Where the fabric points are already banked, generation is one of the remaining levers worth pulling.
• Owners who want lower bills as much as a better band. Solar’s running-cost saving is real and ongoing, so the value case extends beyond the certificate, but on the certificate itself, judge it on cost per point.
• Homes with an unshaded, suitably-pitched, south-ish facing roof. Orientation and shading materially affect both the generation and the EPC uplift.

Solar is a Medium-disruption measure, scaffolding, a day or two on the roof, an inverter and consumer-unit connection, considerably less invasive than a heat pump or wall insulation, but more involved than the quick wins.

RdSAP 10 evidence: keep the MCS certificate

Since 15 June 2025 (STATUS: in force), domestic assessments use RdSAP 10, which scores from evidence. For solar the single most important document is the MCS certificate, it is the evidence the assessor needs, and without it your system may not be credited on the certificate at all.

Have ready for your re-assessment:

• The MCS certificate for the PV installation (the primary evidence document).
• The system size in kWp, panel and inverter details, and the installation invoice.
• If you have battery storage, its details, RdSAP 10 now records battery storage, so an existing battery finally shows up at re-assessment where under older methodology it was invisible. If you have a battery and it is not on your current certificate, that is points you are not being credited.

Under RdSAP 10 an unevidenced system is a system the assessor cannot fully score, so keep every install document together. It is worth adding that the EPC treats the generation rather than any export tariff, the score reflects the modelled electricity the array produces and offsets, so orientation, pitch and shading feed the number directly, which is why a well-designed south-facing install scores better than a compromised one of the same size.

Grants and 0% VAT: the dated reason to act

There is no dedicated grant for domestic solar PV in the way the Boiler Upgrade Scheme funds heat pumps, be wary of anyone implying otherwise. What does apply, and matters, is the tax position.

0% VAT on energy-saving materials covers solar panels and battery storage installed in residential accommodation in Great Britain until 31 March 2027, after which it reverts to 5% (STATUS: law, VAT Notice 708/6). On a £6,000 install that is a real, dated saving and a genuine reason to act before the window closes rather than wait for the 2030 rush. Full detail on our grants and funding page; you can read the underlying guidance at 0% VAT on energy-saving materials (Notice 708/6) on GOV.UK.

Where a household qualifies on low-income or benefits grounds, insulation and heating (not usually standalone solar for owners) may be supported through schemes such as ECO4 in its end phase, check current status on GOV.UK. For most owners, though, the honest position on solar is: 0% VAT until 31 March 2027, and no cash grant.

When solar is the WRONG first move

This is where being straight pays off. Solar is the wrong first move when:

• You have cheaper points still on the table. Spending £6,000 on solar for +8 points while a £25 cylinder jacket, £60 of LEDs, £420 of controls and a £450 loft top-up sit untouched is spending £400-£800 a point when £10-£150 a point is available. Do the cheapest EPC improvements first.
• Your fabric is poor and you are a landlord planning for 2030. The confirmed EPC C by 1 October 2030 standard for privately rented homes is measured across two of the reformed metrics including fabric performance (STATUS: confirmed government policy, 21 January 2026, awaiting secondary legislation reported for 2027). Panels do not insulate a wall, a score propped up by generation alone may not survive the split into a fabric metric. Insulate first; see our insulation guide.
• Your roof is heavily shaded, north-facing or structurally unsuitable, the generation, and therefore the EPC uplift, will disappoint.
• You are chasing a single band jump on the tightest budget, cheaper measures almost always get you there.

The sequence that works is consistent across this whole site: cheapest points first, fabric second, and solar (or a heat pump) as the finisher that closes the last gap. When you are ready to work out how many points you actually need, start from your current rating on the homepage or check it free via the national EPC register.

Frequently asked questions

How many EPC points do solar panels add?

A typical ~4 kWp domestic system adds around +6 to +15 SAP points, with published guides ranging from +6 to +10 up to +10 to +15 depending on the property, because on-site generation offsets the modelled running cost that drives the score. The exact figure depends on system size, roof orientation, shading and your starting fabric, so it is a property-specific number, not a guarantee.

Are solar panels a cheap way to improve my EPC?

No, solar is a mid-table value measure. At £4,500 to £8,000 installed for +6 to +15 points, it works out at roughly £400 to £800 per point, against £50 to £100 per point for loft insulation and even less for LED lighting and a cylinder jacket. Solar earns its place as the finisher after the cheap points, often as the measure that lifts a solid C into B, rarely as the first move.

Is there a grant for solar to improve my EPC?

There is no dedicated cash grant for domestic solar in the way the Boiler Upgrade Scheme funds heat pumps. What applies is 0% VAT on energy-saving materials, which covers solar and battery storage on residential property until 31 March 2027, after which it reverts to 5% (STATUS: law, VAT Notice 708/6). Treat that dated window as the reason to act sooner rather than later.

Does a solar battery show on my EPC now?

Yes, battery storage is recorded under RdSAP 10, in force since 15 June 2025 (STATUS: in force), where under older methodology it was effectively invisible. If you already have a battery and it is not shown on your current certificate, you are not being credited for it, so make sure it is evidenced with the MCS certificate at your next assessment.

Will solar still score well under the new EPC metrics?

The government’s 9 March 2026 partial response proposes replacing the single cost metric with four headline metrics, energy cost, fabric performance, heating system and smart readiness, produced with the Home Energy Model (STATUS: proposal, targeted from October 2026, not law). Generation feeds the energy-cost side, but it does not touch fabric performance, so the same warning applies under the reformed regime as under today’s: solar complements a good fabric, it does not replace one. Fabric-first, solar-as-finisher scores sensibly under both.