SUSTAIN ENERGY (UK) LTD

What SUSTAIN ENERGY (UK) LTD does

Sustain Energy (UK) Ltd is a privately held, Birmingham-based residential energy efficiency installation company registered in England and Wales (Company No. 06734886, VAT 174 8098 72). The company's core activity is the installation of insulation (cavity wall, loft, room in roof), heating systems (gas, oil and LPG boilers), and renewable energy products (solar PV with battery storage), primarily delivered under the UK government's Energy Company Obligation (ECO) "Help to Heat Scheme" to households in fuel poverty. Its customer base is dominated by low-income homeowners and private tenants in receipt of qualifying benefits (Child Tax Credit, Working Tax Credit, Universal Credit, Pension Guarantee Credit, Income Support, Income-based JSA, Income-related ESA), with a secondary focus on off-gas-grid properties within an 80-mile radius of central Birmingham.

The company's underlying technology is operational rather than digital: it deploys accredited in-house installation crews executing conventional retrofit measures (injected cavity wall insulation, loft roll installation, condensing boiler replacement, solar PV mounting and battery integration) using products from established manufacturers including Baxi, Vaillant, Worcester, and Grant UK. There is no proprietary software, no API, no AI component, and no mobile app. The business is differentiated by a dense regulatory and accreditation stack — Trustmark (Reg 15113 under NICEIC), Gas Safe, CIGA, BBA, GD-Approved Installer/Provider, Achilles, Constructionline, and RECC — which collectively authorise it to deliver the full ECO measure set and to access both grant and private-pay procurement channels.

Commercially, Sustain Energy operates a sales-led, direct-response go-to-market using Freephone and landline numbers, website enquiry forms, and organic social presence on Facebook, Twitter and LinkedIn. Revenue derives from two streams: (i) fully grant-funded installations under ECO for benefit-recipient customers, with payment flowing through obligated energy suppliers, and (ii) finance-plan or one-time-payment installations for able-to-pay households (gas boilers from £29.99/month, solar PV and battery storage on finance). Marketing emphasises bill savings of up to £450/year per boiler and up to £240/year from loft insulation, targeting fuel-poor and off-grid households. The business is single-site (Unit 4, Octagon Business Centre, Miller Street, Birmingham, B6 4NF) and operates with no disclosed external investors, subsidiaries, M&A activity, or leadership transitions.

Name

SUSTAIN ENERGY (UK) LTD

Legal name

Sustain Energy (UK) Ltd

Website

https://sustainenergy.co.uk

Company type

Private

Operating status

Operating

Short description

Sustain Energy (UK) Ltd is a Birmingham-based residential energy efficiency installer delivering insulation, boiler, and solar PV/battery installations primarily under the UK government's ECO Help to Heat Scheme to low-income and off-gas-grid households within 80 miles of Birmingham.

Ownership category

akta.pro rank

Product category

Residential Energy Efficiency Installation

NAICS

Drywall and Insulation Contractors (238310)

akta.pro primary industry

Repowering, Augmentation & Retrofit Integration (Capacity Expansion) (EUAEAEAL)

Keywords

• Home insulation services
• Boiler installation
• Solar PV systems
• Energy efficiency upgrades
• Government ECO scheme

Headquarters

HQ city

Birmingham

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2C

Offering type

Services

Cost components

Personnel, Operations, Supply Chain, Marketing or Sales, Technology or R&D, Others

Revenue model

1. Government Grant Funded Installations (ECO Scheme): Installation of energy efficiency measures under the government 'Help to Heat Scheme' part of Energy Company Obligation (ECO). These installations are typically fully funded for qualifying customers who receive government benefits. Revenue derived from government funding obligations rather than direct customer payments.
2. Finance Plans for Non-Qualifying Customers: For customers who do not qualify for free installations, the company offers financing options. Gas boilers available from £29.99 per month. Solar PV and battery storage available on finance. One-time installation revenue for able-to-pay customers.

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels2 records

Core offering

Sustain Energy (UK) Ltd is a residential energy efficiency installation company that installs cavity wall, loft and room-in-roof insulation, oil/LPG and gas boilers, and solar PV with battery storage. The company operates primarily under the UK government's Energy Company Obligation (ECO) "Help to Heat Scheme", providing fully funded installations for qualifying low-income households and finance or able-to-pay options for other customers within an 80-mile radius of central Birmingham.

Product overview

Sustain Energy (UK) Ltd is a home energy efficiency installation company offering a unified portfolio of insulation, heating, and renewable energy products primarily under the government 'Help to Heat Scheme' part of the Energy Company Obligation (ECO). The core product line comprises Cavity Wall Insulation, Loft Insulation, and Room in Roof Insulation (offered free to eligible households), Oil and LPG Boilers and Gas Boilers (with grants or finance options), and Solar PV with Battery Storage (available on finance or able-to-pay basis). The company operates as a single-service installation business focused on residential energy efficiency measures within 80 miles of central Birmingham.

Differentiator

Problem solved

Functional benefit

Products and services

• Cavity Wall Insulation Insulation injected into the cavity between twin exterior walls of a home to restrict heat transfer and reduce heating costs; free to qualifying households under the ECO scheme and prevents up to 35% of heat loss through walls.
• Loft Insulation Insulation installed in loft spaces to trap heat inside the home; free to qualifying households under the ECO scheme and effective for at least 40 years, with installation completed in less than a day.
• Room in Roof Insulation Insulation for loft rooms and attic conversions, fully funded under ECO grants to bring the room up to current building regulations.
• Oil and LPG Boilers Installation of new A-rated condensing boilers for oil and LPG heating systems, with 100% grant-funded replacement for eligible households under the ECO scheme (brands include Grant UK).
• Gas Boilers Installation of gas boilers available on a low-rate finance plan from £29.99 per month, with grants available through the Help to Heat Scheme for eligible homes (brands include Baxi, Vaillant, Worcester).
• Solar Photovoltaic (PV) Systems Solar panel electricity systems that capture the sun's energy using photovoltaic cells to generate free electricity from sunlight, including on cloudy days; offered on an able-to-pay or finance basis.
• Battery Storage Energy storage systems that store electricity generated by the company's solar PV installations for later household use, reducing reliance on the grid and lowering electricity bills.

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Partnerships

Three partnerships are on record, tiered core and supporting.

• NICEICcoreStrategic or Co-development PartnerTrustmark Registration under NICEIC to install External Wall Insulation, Cavity Wall Insulation, Internal Wall Insulation, Gas Boilers, Heating Controls, Room in Roof Insulation and Electric Storage Heaters.
• Trade Direct InsurancecoreOthersBusiness insurance provider covering £5m Public Liability and £10m Employers Liability. Required coverage for installation operations.
• RICS Dispute Resolution ServicesupportingOthersUses RICS Dispute Resolution Service as an alternative dispute resolution service for customer complaints.

Scale indicators5 records

Recent moves4 records

Expansion highlights4 records

Broad incumbents

• E.ON UK: Major UK energy supplier with an established home solutions division installing insulation, heating systems, and solar under ECO and other government schemes. Comparable to Sustain Energy because of overlapping ECO delivery and similar multi-product home efficiency offering, though operating nationally with deeper marketing budgets.
• ScottishPower: UK energy supplier that delivers home insulation and heating upgrades under ECO obligations. Comparable to Sustain Energy in the retrofit/ECO channel and customer segments, but operating across the whole of GB with an integrated supply-and-install model.
• OVO Energy: UK energy supplier (now combined with SSE retail) offering insulation, heating, and renewables to domestic customers, including through ECO-funded programs. Comparable to Sustain Energy in product mix and ECO exposure, with far greater scale and a national service network.
• SSE: Major UK energy company (now part of OVO's retail platform) with a home services division delivering insulation, heating, and renewable installations. Comparable retrofit product mix to Sustain Energy with overlapping ECO exposure, though with substantially larger scale and broader geographic reach.
• British Gas (Centrica): UK's largest domestic energy and home services provider, delivering boiler installations, insulation, and renewables through both paid and ECO-funded channels. Comparable because it competes for the same ECO-funded retrofit work and operates a multi-product home efficiency proposition, but at vastly greater scale and national footprint.
• EDF Energy: UK energy supplier that installs insulation, heating, and renewable systems under government-backed retrofit schemes. Comparable product set and ECO funding exposure to Sustain Energy, but serving a national customer base and able to cross-subsidize installation work from supply-side margins.

Emerging players

• Utilita: UK energy supplier focused on prepayment and lower-income households, with growing involvement in ECO-funded insulation and heating upgrades. Comparable to Sustain Energy because of its similar customer-segment focus (means-tested, fuel-poor households) and ECO delivery model, though structured as a national supplier rather than a regional installer.
• Calisen: UK smart meter and energy infrastructure installer expanding into broader home energy services including retrofit and renewables. Comparable to Sustain Energy as a directly-employed installation workforce delivering energy efficiency upgrades to households, though with a focus on metering and larger infrastructure contracts.
• Octopus Energy: Fast-growing UK energy retailer with an expanding home services arm covering heat pumps, solar, and battery installations. Comparable because it increasingly competes for ECO and retrofit-funded work and offers similar low-carbon home upgrades, but with stronger consumer brand and tech-led acquisition.

Direct peers

• Pimlico Plumbers: London-headquartered plumbing, heating, and boiler installation specialist serving domestic customers with both paid and scheme-funded work. Comparable to Sustain Energy because it directly competes for domestic boiler installation jobs and offers financing, but with a London-centric footprint and stronger consumer brand.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat2 records

Key risks6 records

Key highlights7 records

Customer concentration

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about SUSTAIN ENERGY (UK) LTD