Solar Grants in Hertfordshire: What's Available in 2026

The grant landscape for solar, batteries, heat pumps and energy efficiency is more complex than most homeowners realise. Hertfordshire residents have access to several active schemes — but eligibility varies significantly.

ECO4 and Local Authority Flexible Eligibility

The Energy Company Obligation (ECO4) runs through March 2026 with possible extension. ECO4 funds energy efficiency measures for low-income and vulnerable households.

Hertfordshire access points:

• St Albans City and District Council — active LA Flex scheme
• Watford Borough Council — active LA Flex scheme
• Three Rivers District Council — active LA Flex scheme
• Welwyn Hatfield Borough Council — active LA Flex scheme
• Hertsmere Borough Council — active LA Flex scheme

For a comparable East Midlands grants overview, see Carbon Legacy's 2026 East Midlands grants analysis — the underlying schemes are the same UK-wide, with district-level eligibility variation.

Boiler Upgrade Scheme

The BUS provides £7,500 toward an air source heat pump installation, or £7,500 for a ground source heat pump.

Eligibility:

• Property in England or Wales
• Owner-occupied or private rental
• Existing fossil fuel system being replaced
• Valid EPC certificate
• MCS-certified heat pump installer

Hertfordshire BUS uptake has grown sharply through 2025-26. The grant materially changes ASHP economics for properties with existing oil or gas systems.

Great British Insulation Scheme (GBIS)

GBIS provides insulation grants for households in lower EPC bands. Award amounts:

• Cavity wall insulation: £1,500-£2,500
• Loft insulation: £600-£1,200
• External wall insulation: £4,000-£8,000

VAT Treatment: 0% Through 2027

Solar panels, batteries, heat pumps and insulation all qualify for 0% VAT through March 2027 — a 20% saving versus pre-2022 rates.

Smart Export Guarantee

For homeowners outside grant eligibility, the Smart Export Guarantee remains the primary financial mechanism. SEG payments come from your electricity supplier and pay you for excess solar exported to the grid.

How to Apply

Grant applications are typically routed through approved installers rather than directly. We're a Trustmark-registered, MCS-certified installer with full PAS 2030 accreditation, and we handle grant administration as part of the installation process.

For a free Hertfordshire grant eligibility assessment, get in touch.