Solar inverter installed in a UK new build utility room

Solar inverters

Solar inverters for UK new builds

The inverter is the heart of a new-build solar PV system — it converts panel DC to grid AC, manages the battery, and integrates with the heat pump and EV charger. Here are five brands commonly fitted on UK new builds in 2026.

Ask about inverters FHS PV calculator

Quick answer

For most UK new builds in 2026, specify a hybrid solar inverter (PV + battery + grid in one unit) sized at 80-110% of the PV array kWp. SolarEdge HD-Wave and SunSynk are the most-installed; Enphase for shaded roofs; GivEnergy for UK manufacturer support.

Five inverters commonly fitted on UK new builds

Brand	Type	Typical size	Cost installed	Warranty
SolarEdge HD-Wave	Hybrid + optimisers	3-10 kW	£820-£1,400	12 yr (ext. to 25)
SunSynk	Hybrid	3.6-12 kW	£740-£1,650	10 yr
Enphase IQ8	Micro (per-panel)	1 per panel	£140-£180/panel	25 yr
GivEnergy	Hybrid (UK-made)	3-10 kW	£780-£1,500	10 yr
Fronius Primo	String / hybrid	3-8.2 kW	£950-£1,800	10 yr (ext. to 20)

Hybrid vs string vs micro-inverter — choosing for your new build

Three architecture choices exist for a new build inverter:

Hybrid inverter: PV input + battery storage + grid tie in a single unit. The default for FHS-spec new builds because of the high probability of battery addition (now or later).
String inverter (PV only): Lower upfront cost but requires a separate AC-coupled battery later (~£600 extra plus a second unit on the wall). Best where there is zero future battery intent — increasingly rare on FHS new builds.
Micro-inverter (one per panel): Panel-level monitoring and shade tolerance. Best for partial-shade roofs or split-orientation arrays. £800-£1,200 premium over string/hybrid on a typical 8-12 panel installation — worth it where shade is severe; rarely worth it on south-facing unshaded new-build roofs.

Inverter sizing for FHS-spec arrays

Inverter capacity is typically sized at 80-110% of the PV DC capacity. The slight undersize ("oversize-PV") approach (e.g. a 3.6 kW inverter on a 3.74 kWp array) is standard UK practice — exploits the fact that the array rarely operates at full nameplate output, so the inverter doesn't need to be capable of the peak DC power.

House type	Reference array kWp	Inverter at 80–110% (no battery plan)	Inverter (with battery plan)
3-bed semi (42.5 m²)	3.74	3.0–4.1 kW string	5 kW hybrid
3-bed detached / 4-bed semi (50 m²)	4.40	3.5–4.8 kW string	5 kW hybrid
4-bed detached (65 m²)	5.72	4.6–6.3 kW string	6 kW hybrid
5-bed detached (95 m²)	8.36	6.7–9.2 kW string	8-10 kW hybrid

If you're planning EV charging at >7 kW or significant ASHP loading concurrent with PV generation, specify a 1.2-1.5× oversized inverter to support the higher peak load.

For inverter sizing on your specific plot, use the FHS PV calculator. To ask about PV and inverters for your site, send us your site details (we reply by email).

40% of ground floor area

PV / ground floor area

Mar 2027

FHS in force

75%

CO₂ vs 2013 baseline

£4,350 per dwelling

Per-plot premium (2025 prices, FHS Impact Assessment)

For developers and housebuilders

Solar inverters on volume new-build programmes

On a multi-plot programme, settle four things at procurement: the per-plot price and how it moves with inflation; whether the array is modelled in the SAP 10.3 calculation for every house type; what your structural warranty provider needs to see for roof-integrated PV; and who issues the MCS certificate at handover, since buyers need it to claim Smart Export Guarantee payments.

Developer guide →

For self-builders and architects

Solar inverters for one-off custom builds

On a one-off build the array is easiest to settle at RIBA Stage 2 or 3, while the roof geometry is still open. Your SAP assessor models the system for the Part L submission, your building control body signs it off, and PV installed as part of constructing a new dwelling is zero-rated for VAT under HMRC Notice 708.

Self-build guide →

How this fits into the FHS compliance pathway

Every FHS-compliant new build passes three regulatory gates. Solar inverters sits mainly in the second, design-stage Part L compliance, but it affects building control sign-off and the handover documents too:

1
Planning permission Solar PV designed into a new dwelling is normally covered by the dwelling's own planning permission. Conservation areas, Article 4 directions and plots within the curtilage of a listed building need extra planning evidence, usually prepared by the architect or planning agent.
2
Building control: Part L compliance SAP 10.3 is the compliance calculation at FHS launch. The dwelling's emission and primary energy rates must meet their targets, with the PV array, heat pump, fabric U-values and air permeability all entered. The SAP assessor prepares the design-stage and as-built calculations that building control reviews.
3
Completion: certificates and handover The MCS certificate (needed for Smart Export Guarantee payments), the Energy Performance Certificate and the homeowner's handover documents. If your structural warranty provider has requirements for roof-integrated PV, confirm them before the roof goes on.

For a fuller walkthrough of the compliance process, see the Part L 2026 guide and the FHS PV calculator, which sizes a compliant array from your ground floor area.

Solar inverter FAQ

What inverter is best for a UK new build?

For most UK new builds: SolarEdge HD-Wave or SunSynk hybrid inverters are the default. SolarEdge HD-Wave (with per-panel optimisers) is best for partial-shade roofs and split-orientation arrays. SunSynk is best for the broadest combination of PV + battery + grid-tied features at competitive pricing. Enphase micro-inverters are best where panel-level monitoring matters or shading is severe. GivEnergy hybrid is best for UK manufacturer support and integration with GivEnergy batteries.

Hybrid vs string vs micro-inverter — which?

On a typical FHS-spec UK new build, a hybrid inverter is almost always the right choice — it combines PV input, optional battery storage and grid connection in a single unit. String inverters without battery support require a separate AC-coupled battery later (~£600 extra). Micro-inverters are panel-level (one per panel) and best where individual panel monitoring matters — typically the £800-£1,200 premium isn't worth it for non-shaded south-facing new build roofs.

What size inverter do I need?

Inverter capacity is typically sized at 80-110% of the PV array DC capacity. For the 3.74 kWp reference array on a 42.5 m² ground floor: a 3.6 kW inverter is common. For 5.72 kWp: about 5 kW. For 8.36 kWp: 6-8 kW. An inverter above 16 A per phase (about 3.68 kW single-phase) takes the connection beyond G98, so the installer normally makes a G99 application to the network operator. If you're planning future battery storage or EV charging, specify a 1.2-1.5× oversized inverter to support the higher peak load.

How long do solar inverters last?

Inverter warranties are typically 10 years standard; most major brands offer 15-25 year extended warranties at additional cost. SolarEdge offers 12-25 years; SunSynk 10 years; Enphase 25 years on micro-inverters; GivEnergy 10 years. Expected operational life: 12-15 years for string/hybrid inverters; 20-25 years for micro-inverters. On a 25-year panel installation, expect one inverter replacement at ~year 12.

FHS in force from 24 March 2027

Ask about solar for your new-build site

Tell us about the site, the house types and when you expect to start, and we reply by email. This site is an independent publisher, not an installer.

✓ Sized with equation 5.1 of Approved Document L 2026
✓ For developer programmes, contractors, architects and self-builds
✓ Check any installer against the MCS register before you sign

Run the FHS compliance checker

Send us your site details

We reply by email. Phone is optional.