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REGO Certificates Explained

Renewable Energy Guarantees of Origin (REGOs) are the UK mechanism that proves a megawatt-hour came from a specified renewable source. Suppliers retire REGOs against customer sales to support fuel mix disclosure and green tariff marketing. REGOs are not the same as physical electrons routing to your site; they are documentation. Understanding that distinction keeps SMEs honest with stakeholders and avoids greenwashing complaints when combined with grid import.

Next step: If you use under about 50,000 kWh a year, you can get a quote in under 90 seconds online — fast, no obligation. Larger supply, half-hourly metering, or prefer chat? Use the contact page.

How REGOs flow from generators to your invoice

Accredited renewable generators receive REGOs for eligible output. They can sell certificates to traders or suppliers. Licensed electricity suppliers retire REGOs against volumes sold to customers who purchase green products. Ofgem administers the scheme; market participants must follow registry rules. Your business still takes standard grid power physically; the REGO retires the environmental claim associated with your MWh.

When evaluating tariffs, read green energy tariffs for business alongside this guide so you understand price premium versus certificate sourcing.

REGOs and reporting (SECR, PPn 06/21, voluntary schemes)

Companies in scope of Streamlined Energy and Carbon Reporting (SECR) report UK energy and emissions in financial filings; the treatment of market-based versus location-based electricity factors follows GHG Protocol guidance and current UK conventions. Public sector suppliers may reference Procurement Policy Note 06/21 for low-carbon procurement metrics. Voluntary net-zero pledges often layer REGO-backed consumption with scope 1, 2 and 3 emissions accounting choices—finance and sustainability leads should align narratives.

Price, liquidity, and reputational risk

REGO prices fluctuate with supply and demand of certificates. Cheap REGOs can attract criticism if stakeholders expect project additionality. Some firms pair REGO-backed supply with PPAs or on-site generation to strengthen their story.

Questions for your supplier or broker

Ask which vintage years apply, whether certificates are UK-only, how retirement is evidenced on invoices or annexes, and what happens if portfolio supply changes mid-contract. Microbusiness protections under Ofgem rules do not remove the need for clear green product definitions.

REGO diligence checklist

How REGOs interact with UK fuel mix disclosure

Suppliers publish fuel mixes reflecting their overall sales portfolio and certificate retirements. Customers on standard products see an average; those on specified green products should receive documentation tying retirements to their MWh. Understanding that mechanism helps finance explain why a “100% renewable” tariff still involves pooled grid physics—it is not a scam when described honestly, but it is a problem when sales teams imply dedicated electrons.

Biomass and biogas REGOs carry distinct stakeholder optics compared with wind or solar. If your charity constitution or investor policy restricts certain technologies, read the annex rather than the headline. Retain PDF evidence for at least the reporting period your auditors review.

International links, Guarantees of Origin, and Brexit nuances

Some portfolios blend UK REGOs with imported guarantees of origin depending on supplier sourcing. If your policy restricts imports, specify UK-only retirement in the contract. Post-Brexit arrangements evolve; sustainability teams should not assume yesterday’s rules match tomorrow’s annex.

Large customers sometimes request independent attestation of retirements for loan covenants—ask whether your supplier can accommodate auditor calls.

When switching suppliers, obtain closing and opening retirement statements so reporting years do not contain gaps that look like consumption spikes.

Remember REGOs answer “what attribute was retired against my MWh?” not “did the electron touch my wire?”. Used honestly, they support transparent green tariffs; used sloppily, they invite greenwashing allegations. Keep paperwork as boring and complete as your VAT files.

For audit readiness, store supplier emails that confirm retirement batches alongside the formal certificate extract. Email trails help when account managers change mid-year and nobody recognises your prior arrangement.

If your organisation translates claims into Welsh or other languages for local stakeholders, ensure technical accuracy—mistranslating “matched by certificates” as “directly delivered” has caused reputational issues for public bodies.

When suppliers bundle REGOs into a single p/kWh, ask for a sensitivity table showing certificate cost as its own line—Ofgem expects transparency in green product descriptions, and finance should see what happens if wholesale power falls but environmental certificates rise. Multi-site portfolios should reconcile retirements MPAN-by-MPAN annually; a head-office aggregate certificate can mask a site that accidentally reverted to standard supply after a tenancy change.

Related guides

Continue with how to get renewable business energy, carbon footprint reporting for SMEs, and the energy hub.